this month - Cahaba Technology

this month - Cahaba Technology
focus
on
communications
technology.
..
magazine
this month
two-meter transverter
ssb speech processing
modular vhf fm
receiver
fm deviation
measurements
We built every imaginable feature
into the CX7A.
Including rembiriiiiy
The CX7A was designed as the
amateur's ultimate rig and every
conceivable feature you could want
was incorporated.
As you can imagine, this design
resulted in some pretty complicated
circuitry. And at first there were bugs.
There always are when you're treading
new paths.
Some of the first sets did their
job so enthusiastically they went right
up in smoke. So we went over the
problems with a fine-toothed comb.
We learned a lot, and we did something
about it.
Now we buy only the finest
components obtainable. And we check
each component individually. Every
resistor, every semiconductor, every
whatever, is "burnt-in" before it's put in.
So now when you crank up a CX7A
it'll smoke all right - with the heaviest
talk power and most sensitive receiver
of any rig you can buy. And you can
rely on that. For it, you pay $2,195.
See the CX7A at your signal/one
dealer. Or write us for a detailed
brochure about it. Then buy one. You'll
be the most
reliable
operator
in town.
-
a subsrdiary of
Computer Measurements, Inc.
1645 West 135th Street
Gardena, California 90249
Phone: (213) 532-9752
One Setting for TOTAL BAND COVERAGE...
.
Lowest SWR-PLUS!
Bandwidth at its broadest! SWR 1.6 to 1
or better at band edges.
Hustler exclusive trap covers "Spritz"
extruded to otherwise unatta~nable
close tolerances assuringaccurate and
permanent trap resonance.
Solid one inch fiberglass t r a p forms
for optimum electrical and mechanical
stability.
Extra heavy duty aluminum mounting
bracket with low loss-high strength
insulators.
All sections ll/." heavy wall, high
strength aluminum. Length 21'5':
BUY
mm
Stainless steel clamps permitting ad~ u ~ t m e n t w i t h o damage
ut
to the alumin u m tubing.
Guaranteed to be easiest assembly of
any multi-band vertical.
A~~~~~~ has 3/sW.24 stud at top to accept RM-75 or RM-75s Hustler resonator
for 75 meter operation when desired.
11
I[1
11 I1
Top loading on 75 meters for broader
bandwidth and higher radiation efficiency!
Feed with any length 50 ohm coax.
Power capability-full legal l i m i t on SSB
and CW.
11
f h
MODEL 4-BTV
.choice
. . buy of
thethousands!
verified
A v & j b / e from all distributors
who recognize the best!
$42.95
AMATE"
NET
Wgt 15 Ibs.
NE W-TRON/CS CORP.
1 5 8 0 0 COMMERCE p~~~
B R O O K PARK, O H I O 44142
World Wide Export Roburn Agencies, Inc., 349 W. 14th St.. New York, N.Y. 10014, Cable Address: Roburnage-NewYork
More Details? CHECK-OFF Page 94
february 1972
1
CONSIDERABLY
SPECIAL
CONSIDERING
THE
SPECS
NEW 2 METER F M TRANSCEIVER
Frequency
Modcl SRC-146
..................143-149 MHz
(2MHz spread)
N~rmberof channels .......................5
Supplied with 146.94 simplex.
146.341.94 (same plug in
crystals as SK-CX26M)
R.F. Output ..............1 watt minimum
Sensitivity ..................better than 0.4
uv120 DR Q.S.
Audio output ....................... 500 mw
Meter ......monitors battery voltage on
Tx, S Meter on Kx
Current drain ................... 400 maTx.
15 m;tKx SRY
Size .....8%" high x 3" wide. x 1%" deep
Weight ...........................24 oz.. less
batteries
( ) p t i o n \ : external rnic. or mic-speaker. stubby flexible
antenna. desk top charger, leather case.
I
Consider the new VHF-FM hand held Transceiver by Standard Communications Corp., u 1111 cuclustve Astropo~ntdewan. I-or complete spec~ficationsand the name of your nearest dealer. urtte:
STANDARD COMMUNICATIONS CORP.
639 North Marine Avenue. Wilminglon. (';rliforni;t 90744. ( 2 13) 775-07x4
2
february 1972
More Details? CHECK-OFF Page 94
I
February, 1972
volume 5, number 2
staff
James R. Fisk, W l D T Y
editor
Douglas S. Stivison, WA 1KWJ
assistant editor
Nicholas
D. Skeer. KlPSR
- vhf editor
J. Jay O'Brien, WGGDO
f m editor
Alfred Wilson, W6N IF
James A. Harvey, WAGIAK
associate editors
Curt J. W i n
art director
contents
Wayne T. Pierce. K3SUK
cover
T. H. Tenney, Jr. W l N L B
publisher
Hilda M. Wetherbee
advertising manager
off ices
Greenville, New Hampshire 03048
Telephone: 603-878-1441
ham radio magazine is
published monthly by
Communications Technology. Inc
Greenville, New Hampshire 03048
Subscription rates, world wide
one year, $6.00, three years, $12.00
Second class postage
paid at Greenville, N. H. 03048
and at additional mailing offices
Foreign subscription agents
United Kingdom
Radio Society o f Great Britain
3 5 Doughty Street, London WC1, England
All European countries
Eskil Persson, SM5CJP. Frotunagrand 1
19400 Upplands Vasby, Sweden
African continent
Holland Radio, 143 Greenway
Greenside, Johannesburg
Republic of South Africa
Copy right 1972 by
Communications Technology, Inc
Title registered at U. S. Patent Office
Printed by Wellesley Press. Inc
Wellesley, Massachusetts02181. USA
ham radio 1s ava~lablet o the bllnd
and physically handcapped on magnetic tape
from Science for the B l ~ n d
221 Rock Hill Road, Bala Cynwyd
Pennsylvania 19440
Microfilm copies of current
and back issues are available
from Un~versityMicrof~lms
Ann Arbor, Michigan 48103
Postmaster: Please send form 3579 to
ham radio magazine. Greenville
New Hampshire 03048
6 digital station accessory
E. H. Conklin, KGKA
20 solid-state final amplifier
C. Edward Galbreath, W3QBO
24 two-meter transverter
Louis E. Savoie, K1 RAK
32 high- frequency mosfet converter
Michael J. Goldstein, VE3GFN
38 pre-emphasis for ssb transmitters
Veikko Aurnala, OHZCD
4 2 two-meter fm receiver
Harvey L. Wagner, WAZGBF
46 simple crystal checker
Henry D. Olson, W6GXN
50 calculating toroid inductance
Michael J. Gordon, Jr., WBSFHC
52 fm deviation measurements
Edward M. Noll. W3FQJ
4 a second look
94 advertisers index
52 circuits and techniques
83 flea market
58 ham notebook
62 new products
94 reader service
february 1972
3
As more and more amateurs switch to
factory-made gear, and as industry uses
more ICs and disposable plug-in modules,
the life of the dyed-in-the-wool homebrewer gets tougher and tougher. If you've
recently tried any of the construction
articles in ham radio, you are already well
acquainted with the hassle involved in
obtaining a few needed components.
At one time you could drop in at your
local corner radio store with a list of
parts and the man behind the counter
would fill your order. But that was when
the vacuum tubes, resistors and capacitors
in your ham gear were the same as those
in the family radio. It's not the same anymore - now the transistors and ICs in
radios and television sets are apt to be
designed specifically for that purpose and
have operating characteristics that are of
little use elsewhere. There are exceptions,
but they are few and far between.
Another problem that faces the serious
home builder is the generous variety of
transistors and ICs available from different manufacturers. Although some types
of devices are made by more than one
company, in most cases the semiconductor manufacturers crank out devices that
are completely different from those of
their competitors. And to add insult to
injury, the same device may carry a dozen
different part numbers: a 2N number, a
replacement number plus special numbers
for units sold in large quantities to equipment manufacturers.
There is only one way to combat this
lunacy: arm yourself with a good semiconductor cross-reference guide and a
wideselection of electronic parts catalogs.
4
february 1972
Tops on the list of replacement guides is
Howard Sams "Transistor Substitution
Handbook." This handy little paperback,
which i s updated every year, covers practically every transistor ever made, from
2N34 to 2N6000, with recommended
substitutes. I t also covers devices from
Japan and Europe, as well as replacement
types manufactured by Delco, General
Electric, International Rectifier, Motorola,
RCA, Semitronics, Sylvania and Workman. Most of these manufacturers also
publish replacement guides, available for
the asking from their authorized distributors.
If you live in a large metropolitan
area, chances are that there i s an industrial electronics supply house that can
fill your parts need. Many of these firms
don't advertise, because they are not
particularly interested in small quantity
sales, but if you show up a t their office,
they will sell you the parts. I f you want
to find them, pick up your telephone
directory and check the Yellow Pages;
look under "Electronic Equipment and
Supplies." If you live out in the sticks,
the problem is more difficult, unless
you can get into the city. If you can't,
you must purchase your components
through the mail. Allied Radio is the best
bet in this case and you can get a catalog
from any Allied/Radio Shack store. Be
sure you getthe Industrial catalog though,
the more common entertainment catalog
is devoted primarily to hi-fi, CB and
simple experimenter's stuff.
Jim Fisk, WIDTY
editor
One-Stop"Shopping"
for Everything You
Want in a
TRI-BANDER
Why s h o p a r o u n d for, a n d p u t together, bits
a n d pieces of a tri-band, two-element q u a d at
greater c o s t particularly when-after a l l i s s a i d
a n d done-Hy-Gain's
complete Hy-Quad delivers
superior performance?
Yes, Hy-Quad is t h e o n l y q u a d that is complete; a n d here
a r e s o m e of i t s features:
Heavy duty mechanical constructlon of swaged aluminum tubing and die-formed
spreader to boom clamps.
Extra-heavy duty universal boom-to-mast clamp that tilts and mounts on any
mast 1%" to 2%" in diameter.
If you really want a blg signal, buy one at the best distributor under the sun. He's
the one that stocks Hy-Gain.
SPECIFICATIONS
Overall length of spreaders .................... .
.
................. 3 0 5
Turning radius.. ......................................................... .13'6
Weight ...................................................................... 42 Ibs.
Boom diameter .............................................
.
.......... 2"
Boom length............. .
..... ...................................... 8"
.........................................1 " to 2l/2"
Mast diameter ...............
.......................................1 0 MPH
Wind survival ...................
Forward gain ..........................................................
8 5 db
Input impedance .................... ..... ....................... 52 ohms
..............................I .2:1 or better at
VSWR .......................................
resonance on all bands.
power
Maximum legal
............................. 25-35 db depending
Front to back ratio .....................
.
upon electrical height.
.
.
.
.
.
.
.
. .
.
Order Number 244
H a m Net $129.95
$!i{:;;;,,
THE HY-QUAD from HY-GAIN
HY-GAIN ELECTRONICS CORPORATION
THE SUN!
P. 0. Box 5407-WB /
More Details? CHECK-OFF Page 94
Lincoln, Nebraska 68501
february 1972
5
digital readout
station accessory
This versatile
station accessory
may be used as a
digital vfo readout,
digital clock,
identification timer,
electronic keyer
or frequency meter
The most attractive magazine articles may
be those that provide instructive or interesting reading to a large percentage of
readers, including those readers who do
not plan to build or use the device
described. It is hoped that this article will
be of that type.
6
february 1972
Possibly each of us should plan to
build one electronic gadget every year,
just to avoid becoming entirely an "applicance operator." This i s not easy to do
under present conditions other than for
small items of accessory or test equipment. Of all the gadgets other than kits,
digital nonlinear integrated circuits offer
perhaps the most pleasant areas in which
to experiment, design and build an accessory for your station. There is widespread
interest in such devices, as will be seen
from the many technical papers which
have been published during recent years.
r
Instead of building a series of devices
to accomplish different things, I have
-2
given consideration to the idea that one
cabinet, chassis, power supply and readout can be used for an almost endless
number of jobs. This saves construction,
space and expense. By using some form
= of plugboard for the circuitry, new active
devices can be added, or replaced even
temporarily, such as when you are asked
; to time a swimming meet or auto race to
a thousandth of a second.
$
m
I plan to cover the basic unit a t this
d time, and the detailed accessory devices
in coming months. Some of the accessories will not be the subject of an article
because of the number of similar units
Y
already in print. These can be built on
5 suitable plugboards and used in the acceso
sory unit.
In the meantime, general planning and
w
z
om
background reading well may be in order
to acquaint you with the subject. This
will make the subsequent plug-in devices
very easy to understand. In fact, they
may not even require a circuit diagram,
except for block diagrams and switching
plans for the station maintenance files.
Some of the items that can be worked
into the accessory are: high-stability
crystal calibrator, harmonic generator,
frequency counter, digital clock, identification timer, receiver digital dial, transmitter digital dial, general-purpose receiver dial, electronic keyer, event timer
or stopwatch, auto speed trap, photo
timer and wife-reminder. The wifereminder refers to anniversaries, birthdays
and the like. These, and license renewal
date, can be added, with suitable alarms
for the purpose!
In preparing such an article, it is
desirable to simplify parts procurement in
order to eliminate a month or two of
planned purchasing, with the inevitable
back-ordering and interdependence of
one item on what i s obtained for some
other requirement. Also, chassis and
cabinet dimensions given are for the very
few that matter. And finally, difficult
machining problems and other sources of
frustration and discouragement should be
avoided.
nixie read-out displays
Chassis construction depends to a considerable extent upon the type of readout displays that you select. Tube-types
such as Nixie (a Burroughs trade name)
and Numatron (RCA) may require a
specific chassis height, or shelf, or mounting on the forward edge of vertical
epoxy-glass circuit boards. It i s feasible to
use a chassis only in the center to support
the read-out tubes and the power supply
with all other parts except panel switches
mounted on plugboards (such as Vector
plugbords).
The widely known Nixie gas-discharge
display device requires a few milliamps a t
about 180 volts. It also requires a highvoltage BCD-to-decimal decoderldriver
IC. As in other uses of decoders and
drivers, care must be taken to obtain
those with active high or active low
operation as required by the particular
type of read-out. A current-limiting resistor i s used as with neon tubes. Sometimes a grounded wire-mesh screen is
placed over the panel window to prevent
inside radiation from leaking out, or the
reverse.
flg. 1. T w o Mlnltron readouts are shown on the
left. A three-diglt Sperry cold-cathode display,
restlng o n its spsclal socket, and one of the
decoderldriver ICs, are on the right.
These read-outs will be found in large
mail-order industrial catalogs. However,
note that this is a fast-moving field,
and spare tubes should be on hand to
prevent running short if the type you use
is not available in the future.
Burroughs has extended the coldcathode gas discharge design into Pana
plex, a single tube with eight or more 7or 9-segment digits, including driver circuitry. A strobed or multiplexed timesharing method is used to minimize decoderldriver cost. The hoped-for cost of
$1 per digit is a few years away.
In the meantime, Sperry Information
Displays* is producing some very pretty
replacements for Nixie tubes. These are
I%-, 2- or 3-digit flat glass plates, a socket
and active-low 7-segment decoder-driver
units, shown on the right in fig. 1.
Sperry offers demonstration kits including read-out, socket and decoderldriver.
and may furnish the 2- or 3-digit ones on
request a t $14.95 for the lot, thus being
one of the low-cost devices. They do
*Sperry Information Displays Division, Box
3579. Scottsdale. Arizona.
require the low-current 180-volt supply,
though.
General Electric offers the Y-1938
7-segment low-voltage tubes with filament. They have an unusual blue-green
character color and require 1.6 volts on
the filament and 25 volts dc on the
anode, but can be driven by suitable IC
decoderldrivers. General Instrument and
Hughes make upldown counters, buffer
storage, and decoderldrivers in a single
large 24-pin dual in-line package (DIP) IC
that will operate the GE tube. These
combined counter ICs have merits but are
not desirable for digital clock purposes.
incandescent displays
The RCA Numitron is a 7-segment
incandescent tube, taking up to 5 volts,
but at 24 milliamperes per segment. This
requires one of the high-current decoderl
drivers.
There are other simple incandescent
lamp displays, some requiring higher current than i s provided by a 7-segment
decoderldriver IC. One made in Japan,
however, built like a 16-pin DIP IC, i s the
Minitron, shown on the left in fig. 7. Its
5-volt and low-current requirements are
well within normal 7-segment decoderl
driver output, like the inexpensive activelow Monsanto MSD 047 and the Texas
Instruments 7447, all available from Circuit Specialists. * These have provision for
decimal, lamp test and read-out blanking
input and output. Currently the Minitron
and MSD 047 decoderldriver combination appears to be the lowest-priced
read-out system available.
light-emittingdiodes
The Monsanto MAN3A light-emitting
diode read-outs are built somewhat like a
ten-pin IC flat-pack, with pins spaced
0.034 inches. The 7-segment display is
only 0.115 inches high, thus about the
smallest in the business. At around $6.50
a digit this is the lowest cost of the bright
red-colored light-emitting diode displays.
The Heath 14-pin DIP LED display, used
*Circuit Specialists, Box 3047, Scottsdale, Arizona 85257.
8
a february
1972
in their 80-MHz counter, sells for $8.50.
Light-emitting diodes are attractive
and will be very popular when the smallquantity cost comes down a bit. They
require a dropping resistor in each segment lead and each decimal-point lead.
LEDs are compatible with systems that
include the decoderldriver, latch, and
possibly the decade counter, all in the
same IC.
other displays
Sigmatron* has a light-emitting film
multidigit display; in large quantities, this
runs only $1.50 a digit, but unit prices
are much higher. These units require an
aud i o - f requency multivibrator driver
which can be time-shared by all of the
digits with a multiplexing device.
t
Optel offers liquid crystal displays.
These require a small 20-volt supply. With
the decoder/driver and Hughes HCTR
0107 display driver the small-quantity
cost i s much higher than many other
read-outs.
color filters
Usually a color filter is placed over a
numeric display to increase the contrast
between the read-out's light and the
background. Most displays are red, but a
few are blue-green. The incandescent ones
are close to an orange-white color, depending upon the voltage at which they
are operated.
Litronix mentions that the Rohm &
Hass no. 2423 acrylic plastic has 71%
light transmission, and that the Polaroid
HRCP-7 has only 40% light transmission
but offers a nonglare surface. In a test,
Circuit Specialists did not find any advantage in the Polaroid material compared
with sticking red Scotch tape on individual Minitrons and trimming the edges
even.
Plain half-sheets of thin flexible plastic
cost about $1.50 at art supply stores;
similar colors are available at school
supply stores as "report covers" at 19c
'Sigrnatron, 849 Ward Drive, Santa Barbara,
California 93105.
toptel, Box 221 5, Princeton. New Jersey.
each, which is quite a bargain. The red
looks good. For incandescent displays, the
rose (not quite amber or orange) probably passes more visible light, even when
two thicknesses are used.
It is desirable to minimize light spread
by having the plastic window close to the
read-out. The chassis described in fig. 6
has the plugboard holding the displays
directly behind the panel window with
the Minitrons actually touching the
plastic. The plastic can be glued to the
rear of the panel or it can be secured with
flat-head 2-56 machine screws with a
washer and nut on the rear side of the
panel.
For trying different colors, a 3 x 5inch card holder can be purchased a t a
builders' hardware store. This can be held
in place on the rear of the panel with
flat-head machine screws. It is practical to
cut out a section on the 3-inch dimension, mounting the old top and the
remaining side lengths from the upper
machine screws. This has been done on
the panel shown in figs. 2 and 6. Inasmuch as the Minitron read-outs are
thicker than the other ICs there is no
problem in clearances from the panel. If
fewer than eight read-out digits are
planned, such as by omitting the megahertz, smaller escutcheons can be used
without modification.
number of read-outs
The unit pictured in fig. 2 has eight
Minitron read-outs in one row, shared for
all purposes, so that 99 MHz can be
displayed right down to the last cycle. In
some applications it is feasible not to
bother with counters, latches and decoderldrivers for the MHz digits; if these
are available they can be activated by a
bandswitch to connect 5-volts dc through
steering diodes to the correct read-out
segments.
Some read-outs can be omitted, such
as the MHz ones, or the units or tens of
Hertz. It i s quite useful to have only three
kilohertz digits and one for tenths-ofkHz, thus requiring only four read-out
tubes.
Another option is to use two rows of
read-outs, with frequency (counter) on
one row, and time of day on the second
row - if sufficient plugboard contacts are
available. In this way, by not sharing
these displays, there will be the added
cost of the extra read-outs and their
decoderldrivers for the extra four units or
more used to display time.
fig. 2. Front panel and cabinet of the digital
accessory prior to the application of panel
lettering.
There will be some saving on switching, and also about $5 for the four
quadruple 2-input AND gates used as
data selectors on the displays alternately
used for time and for counting. Texas
Instruments promises production of their
SN74157N quadruple 2-line-to-1-linedata
selectors to do this same job of switching
between two types of input data to the
read-outs, but prices are not yet available.
cabinet and chassis
With IC-type read-out displays a miniature unit i s possible, but it limits flexibility in usage and may complicate experimentation, test and maintenance. Readers
with other Heath equipment can select
from a number of cabinets used in many
Heath units.
As a first attempt a t packaging, I
decided to use the gray CO-1 cabinet
made by LMB shown in fig. 2. It measures 14%-incheswide, 6%-incheshigh and
13%-inches deep including the shadow
front. It closely matches Collins S-Line
cabinets and the original Henry 2K.
february 1972
9
Through separate order, the alternate
1%-inch-high chassis - not the more
popular 2-inch-high chassis - was
ordered. These are obtainable through
supply stores. Unlike the Collins cabinets,
i t does not come with a rectangular hole
for access to the rear apron of the chassis.
Such a large rectangular hole can be cut
out, or small guide holes can be drilled
from the rear of the cabinet into the rear
of the chassis and later enlarged to pass
phono plugs through the cabinet into
phono jacks mounted on the chassis.
This operation is facilitated by shimming the rear of the chassis 1/16-inch
r
cabinet and the aluminum chassis to
identify the phono plugs. The Letraset is
smaller than that offered by electronics
mail-order houses; it and other alternatives are available from art supply stores.
Crystal-clear Kry Ion spray coating over
the transferred letters will make them
permanent.
There is no provision for a chassis fuse
nor for a complete on-off switch inasmuch as the oven and clock components
will remain turned on except during trips
abroad. The unit i s fused in the power
plug (Allied Radio Shack no. 27061249).
The large hole required for a power-
;
II:
'"1
0
I
WINDOW
I 4
L,a ------I
'
d
-
0
6)
Fig. 3. Front panel drilling instructions.
with washers held in the corners with
masking tape or by a 4-40 machine screw
permanently threaded into each of the
two rear chassis angle brackets. Scrap
pieces of Vector T-strut can be used to
hold the chassis by placing these pieces in
the guide rail at the sides of the chassis.
By blocking up the chassis from the front
and holding it from popping out, guide
holes for the entire set of phono jacks can
be drilled.
Subsequently, sets of black and white
letters* can be applied to both the gray
'Letraset 10-point Helvetica light (1573).cat*
log number 481BCLN, upper and lower case,
available a t art supply stores.
10
a february
1972
cord strain relief is beyond many home
drilling facilities; a grommet with suitable
tight-fitting hole will do a reasonable job.
Stretch the grommet onto the power
cord, then drill out the chassis hole that
will accept the grommet but retain the
power cord.
The cabinet's cover has no provision
for a handle or finger hole. However, a
4-40 machine screw with fibre washers
and spacer under the head, will pass
through a ventilation hole, to be used as a
cover handle.
If the unit will be near Collins equipment, obtain two or four tapered feet
(Collins 543-8101-002). Four are used
when stacking above or below S-Line
units, maintaining ventilation space.
Rubber feet are Collins 200-5010-000.*
the panel is the right distance back at i t s
bottom, then drill new screw holes up
through the bottom. A sheet-metal screw
0
Q
@
.-A
@-
b
LMmn
@
0
0
0
..~~o-..o..*?'oY!LL!BPUnS'-_LLLLLL.
@
0 0
meeee
@
LMmn
r - 2 4 y 3 -
T.STR"T
- - - - - - - - - - - - - - Q-- ------
.
.
.
(
4
.
(
4
.
.
(
4
(
4
.
.
.
-
@
-----
pi pi+
*[email protected]
Olb' CU 16 PIACESI
OROMMETS
HOLE
0
fig. 4. Chassis drilling instructions; the power-supply holes are omitted because they will not apply
for different parts.
panel
The front panel angle comes secured
under the cabinet cover by two sheetmetal screws which also hold down the
hinged top. This i s inconvenient for adjusting the crystal oscillator and setting
the clock. The answer i s t o clamp a piece
of wood to the lower cabinet lip so that
'Collins parts may be ordered from Customer
Service Representative, Collins Radio Company, Cedar Rapids, Iowa 52406.
should be put into the first hole before
the second is drilled. In this way, the
chassis and the front panel are held
firmly, even when the cabinet lid is
opened.
The lower set of controls will require
holes %-inch up from the panel bottom,
through the chassis, as shown in figs. 3
and 4. Old controls or their bushings then
can be inserted to hold the chassis and
panel in place as additional holes are
drilled.
f e b r u a r y 1972
11
fig. 6. Rear view of digltal accessory showing the mountlng of Vectorboard to hold Minitron
readouts and T-struts for other circuit boards prior to above-circuit chassls wiring.
It can be seen in fig. 5 that the small
space under the chassis permits a switch
only as large as the Centralab PA-1000
and PA-2000 subminiature series. Even
then the switch must be wired when
dismounted, bending contacts in, and
applying plastic tape to the chassis and
cabinet to prevent the contacts from
shorting.
These switches are attractive because
spare parts and wafers are available for
possible future expansion. Smaller
switches may require smaller panel holes
and l/&inch shafts. The small Daka-Ware
knobs that were supplied with the
switches are helpful when positioned so
close to the bottom of the cabinet.
Some controls can interfere with the
.
,
.,.
, ,..
,
.
.-
<
fig. 5. Bottom view of digital accessory showing
and other
Dower SUDDIY and unwired
controls.
read-out plugboard receptacle contacts.
In this case, two control nuts can be used
to mount the central controls far enough
behind the panel in order to clear the
receptacle contacts.
More holes for controls are shown in
fig. 3 than were planned for expected
requirements. Unused holes can be filled
with snapin plugs until required by
future expansion.
read-out window
A rectangular hole i s required in the
panel for the read-out display. This can
be slightly smaller than IC-type read-outs.
The old way of drilling a series of small
holes, then connecting them by one of
several means, is a lot of work. There are
two easier ways.
First, lay out the desired rectangle on
the back side of the panel, marking all
four sides. Drill small holes in all four
corners just inside the rectangle. Then
back away from the corners and drill
large holes inside of the rectangle. If a
neighbor has home shop equipment
with a milling device, a small milling tool
can be used to rout out the metal within
the rectangle.
Without this, borrow a sabre (scroll)
from under $10 at Sears and about twice
that in the Skil tool line. Cloth should be
placed on each side of the panel, then
wood blocks, before putting it in a vise
for sawing. The rectangle can be cut by
sawing in different directions from a
starter hole, even by using the side of the
saw blade as a file for thin cuts.
After the panel work i s finished, hang
the panel by a wire or cord through a
screw hole in the bent-over angle lip (or
through both holes), and spray with
Krylon all-purpose gray (no. 1318) or a
suitable alternate.
The same type of cutting operation
can be used for the rectangular hole for
the contacts of an R-644 Vector plugbord
receptacle on the front of the chassis
below the rectangular window in the
panel.
Later, a Vector 3662 plugbord
($6.95), with P pattern 0.1-inch hole
spacing, can have two inches sawed off
the end of the board, 4-7116 inches from
the plug end, to retain 36 rows of holes
including the two rows connected to the
44 contacts. This board will mount up to
eight read-out units such as Minitron or
light-emitting diodes, plus their decoder1
drivers, and considerably more DIP ICs if
desired.
The drivers should be mounted with
the read-outs in order to have only four
data leads per decade, not seven, to keep
within the limit of 44 contacts. Boards
with more contacts are available, but may
not be necessary.
Normally, mounting the SN7475N
quadruple bistable latches on this board is
not desirable, because latches are to be
omitted from the circuit when time is
being displayed. Of course latches for the
digits not required to display time can be
mounted on this board to use up some of
the available board space here, and relieve
the other circuit boards which will be
used for the time base, and for the
counting functions.
If light-emitting diodes are used as
read-out displays the voltage dropping
resistors required between the decoder1
drivers and the read-outs should be on
this board. There must be sufficient
contacts to handle decimal points. With
eight digits displayed, there may not be
sufficient contacts for future expansion.
hardware
Most of the circuitry is on Vector
using the 3662 mentioned
above for linear rf uses and the 3682-2
($8.49) which has convenient ground and
+ Vcc busses printed on i t for nonlinear
ICs and the input circuitry.
These boards mount in the R-644
receptacles as shown in fig. 6. A convenient means of mounting is available by
obtaining two 24-inch Vector TS240
plugbords
-C1
SECTION
fig. 7. T-Strut lengths and locations of holes.
T w o pieces of Vector no. TS-240 24-inch stock
are required.
T-struts.* The company continues to use
this address although the earthquake
caused them to move to another area.
Also, order a package of 24 NT6-3
plastic inserts, with no. 6 sheet-metal
screws, SC6-11; and a package of 25
square 4-40 nuts, NT4-7. The screws and
inserts make right-angle butt joints possible, and the square nuts are used to
secure to chassis by the center T-slot nut
cavity, and to fasten R-644 receptacles by
one of the two edge T-slot nut cavities.
(Small hex 4-40 nuts will work.)
Saw off, and file smooth, one top
T-strut, one bottom T-strut, and two side
T-struts as shown in fig. 7. Fig. 6 shows
the side T-struts 318-inch longer than the
dimension in fig. 7. This is satisfactory if
the bottom chassis guide rails are wide
enough t o take the chassis plus both side
*Vector Electronics, 12460 Gladstone Avenue,
Sylrnar, California 91342, $1.50 each.
T-struts without more than minor springing, but it i s a close fit.
It i s necessary for the bottom strut to
be shimmed up 0.1-inch above the chassis
with two large washers so that the lower
edge of the plugboards will be above the
chassis surface. Some chassis space could
be saved for pushbutton location by using
two short pieces of strut in lieu of the
long bottom one, and shimming their
ends with washers held in place with
screws through the chassis and up into
nuts in the central T-slot nut cavity. This
would result in a small loss in strength.
chassis holes
The more critical chassis holes are
marked on fig. 4. Adequate 7116-inch
holes for large-hole grommets may be
drilled in front of the lower T-strut and
located convenient to the below-chassis
control wiring. The holes for the crystal
oscillator oven and clock reset pushbuttons were originally planned to be in
front of the bottom T-strut. However,
that results in possible conflict should
nearby panel holes be used for longer
switches or controls in the future.
The hole for an octal socket for the
crystal oscillator oven should be punched
or drilled with a fly-cutter; due to the
thin, soft aluminum the %-inchfly-cutter
center guide drill should pass through a
%-inch bushing taken from an old switch
or potentiometer, temporarily mounted
to keep the drill from wandering.
Suitable holes for the transformers and
power-supply parts, and for adequate
pushbuttons for reset and adjusting the
clock, should be drilled. Switchcraft type
103 are suitable spdt pushbuttons. The
holes for the grounded and the insulated
LM309K 5-volt voltage regulators can be
drilled in the side aprons of the chassis to
save top chassis space and provide adequate heat-sinking.
t-strut assembly
Prepare the lower T-strut (it has no
holes) by inserting a plastic screw insert,
properly oriented in the slot, into each
side T-slot at one end of the lower
14
february 1972
T-strut, then cutting off the flat plastic
that continues to extend beyond the end
of the T-strut. Next, put a sufficient
number of square 4-40 nuts, or small hex
nuts if you do not have the Vector square
ones, into the rear T-slot to take care of
any future expansion. Eight or ten should
be sufficient.
Now put plastic screw inserts into the
other end of the side T-slots, again
cutting off the flat surplus material. Put a
4-40 x 3/8-inch machine screw up
through each of the four holes in the top
of the chassis with a lock washer. On top
of the chassis put on a shimming washer
(not retained by the nut), and then a
square nut, on the two screws that are
clear of the sides. Before tightening the
nuts, slide the lower T-strut onto these
nuts using the central T-slot. Adjust the
position at the sides and tighten the
machine screws.
Next, place plastic screw inserts into
the side T-slots at the top of each side
piece of T-strut (away from the mounting
holes), again removing excess plastic. Put
4-40 x %-inch machine screws, lock
washers and a square nut through the
four holes provided, from inside the
chassis, using the mounting holes. Slide
the side T-struts down cver the square
nuts, using the central T-slots, so that the
side T-struts stand up outside of the sides
of the chassis. Secure the machine screws.
Insert no.-6 round-head sheet metal
screws through the T-strut mounting
holes drilled through the side T-slots and
into the plastic inserts in the ends of the
lower T-strut.
Now, using no.-6 flat-head sheet-metal
screws, secure the top T-strut to the top
of one side T-strut. Then insert the same
number of square nuts into the rear T-slot
of the top T-strut as were put into the
bottom T-strut, and secure the remaining
end of the top T-strut to the vertical side
T-strut. Later, the R-644 receptacles can
be attached - probably after soldering
wires to the contacts. The completed
assembly appears in fig. 6.
After the R-644 receptacles are
attached it may be necessary to bevel
Apparently the LM309K was designed
to have an input voltage of 7 to 25 volts.
Avoid loading the transformer, rectifier
and input capacitor to a lower input
voltage to the regulator. This is provided
by a good 6.3-volt transformer; with a
large filter capacitor of some 8000 pF for
the 5-volt supply, and half that for 10 to
15 volts. A good 2-ampere transformer
for under $4 is the Calectro Dl-747 (GC
Electronics), producing over 9 volts input
to the regulator from a 12-volt centertapped rectifier, before a load is applied.
The use of a 12-volt center-tapped winding permits a bridge rectifier for the
higher voltage, and half that voltage from
the center tap, as shown in fig. 8.
higher voltages
National Semiconductor also produces
the LM336 for 12 volts at about 500 mA,
and the LM337 for 15 volts a t about 400
mA, depending upon both the input
voltage (which should not be excessive)
and the adequacy of the heat sink. With
one of these regulators a center-tapped
transformer of sufficient voltage can be
used simultaneously for the 12- or 15-volt
regulator, and also for the 5-volt regulator.
For that matter, it is feasible to use
two regulators or more for different
voltages from the same higher-voltage
rectifier, provided that the maximum
regulator voltage and heat dissipation
ratings are not exceeded. The higher-voltage regulators are priced around $6. All
three of these ICs are protected by
internal current-limiting.
With any of these power supplies
rectifier diodes that handle 1.5 to 3
amperes may prove convenient. Glassamp units can break unless a l l bends in
the leads are made between two longnosed pliers so that there i s no strain on
the glass.
For current less than about 45 mA the
adjustable type 723 IC voltage regulator
(made by Fairchild and others) may be
used. It is rated up to 150 mA, which
would require a 0.335-inch clip-on heat
16
february 1972
sink if the metal package is selected. The
total internal power dissipation must be
limited to 800 milliwatts. The input
voltage must not exceed 40 volts. There
must be at least a 3-volt drop between
input and output voltages.
The current-limiting resistor, R, can
be selected by dividing 0.65 by the
desired limiting current in amperes, and
frequently is ten ohms (see fig. 9). Approximate values for the Rl/R2 voltage
divider are given in table 1. These figures
are derived from a Fairchild application
note with some adjustment to approach
standard resistor values. R3 is needed
only for minimum temperature drift;
it can be calculated from R1 x R2/
(R1 + RZ), and frequently is around 3k
ohms. Fig. 9 shows a circuit used for an
output above 7 volts.
Avoid blowing out the 723 IC by
accidental application of reversed rectifier
voltage. This can be done by using a series
diode between the rectifier and the IC.
Circuits, including those for externalpass transistors, will be found in the
Fairchild application note for cases where
more than the rated current is to be
regulated by the 723, or the output
voltage is to be below 7 volts.
Keep in mind the much higher peak
input voltage to the regulator. A 15-volt
capacitor or larger is required for the first
filter capacitor at the output of the 5-volt
rectifier diodes, and a 25-volt or larger
capacitor in the 12-volt supply. A lower
break-down voltage capacitor is satisfactory for the output side of the voltage
regulators, just exceeding this regulated
voltage. Generally, a smaller capacitance
is suitable on the output of the regulator,
since additional capacitors generally are
placed on the circuit boards because of
the tendency of TTL flip-flops to create
spikes and noise which can trigger other
flip-flops.
If mica mounting kits are used to
insulate the TO-3 regulator cans, be sure
that there are no burrs around any holes,
and test the unit for high-resistance isolation from chassis or heat-sink with an
ohmmeter before connecting it to other
parts.
In the unit pictured in figs. 5 and 6
one 5-volt power supply is completely
insulated from ground until it is switched
into the circuitry, so a pair of phono jacks
can bring the voltage out to other devices,
such as the Palomar Engineers' electronic
keyer which requires a grounded positive.
Other phono jacks bring out the
grounded 5- and 12-volt supplies for
other uses.
R3.
EL.!%
RI + R2
FIXED
ADJUST
f 10%
fig. 9. Fairchild jLA723-type I C precision
voltage regulator circuit for use above seven
volts, without series-pass transistor. Input must
exceed output by at least three volts.
frequency standard
Initially you can use the 60-Hz power
(or 50-Hz elsewhere with three flip-flops
in a divide-by-five circuit, or the BCD
section of a 7490 decade1) for satisfactory operation of a digital clock and
for equipment digital dials for tenth-kilohertz read-out. This was discussed in ham
radio2 in connection with measurements
made from a line-frequency-controlled
counter using Fairchild 9093 DTL dual
JK flip-flops.
The 9093 flip-flops have toggled on ac
at all frequencies from a few hertz up to
their limit of 2.2 MHz without any input
table 1. Approximate values for the
voltage divldar in fig. 9.
fixed
adjustable
output
output
output
voltage
R1
RZ
R1
RIA
9
1800 6800
750
1k
12
4700 6800 2000
1k
15
8200 7500 3300
lk
28
22000 7500 5600
1k
Rl/R2
210%
RZ
2700
3000
3000
3000
circuitry. Three FFs can divide by two
and three, and four FFs (or a decade
counter) can divide by ten, to give a
one-second frequency. The remaining FF
in the dual units can produce the onesecond on and one-second off frequency
desired for counter gates.
The 9093 and some other FFs can be
driven directly by a volt or so of ac. Some
may require a diode across the input to
pass the negative half of the cycle.
Usually, several volts of ac are available
between ground and a terminal in a
power supply, even from a bridge rectifier
without a transformer center-tap. A
stopping capacitor can be added; then, if
desired, a 2-volt zener or several series
silican diodes can be added with anode
grounded to provide the FF connected
across the zener or diodes with a volt or
two of ac safely. This also eliminates the
unnecessary negative excursion of the ac
sine wave.
Another source of ac is the power line
itself, through a nonpolarized capacitor,
then the resistor and zener3 mentioned
above. With a power-line source the accuracy of a counter will be within about
0.02 percent on any count, and the
average of a number of measurements will
probably be correct.
Be sure to provide an octal socket hole
in the chassis for future addition of an
oven-controlled crystal oscillator. The
common, inexpensive E-cut 100-kHz
crystal is not nearly as good as a DT-cut
crystal for 100 kHz or 1 MHz. The
DT-cut has a broad flat temperature
curve.4 The cost is a few dollars more.
For best results, the crystal and oscillator
should be in an oven.
The counters I have use 100-kHz and
1-MHz oscillator ovens made by Monitor
february 1972
17
Products." One has a 400-kHz crystal, IC
flip-flop oscillator and two frequencydividers which use cross-connected gates.
The 100-kHz output is suitable to drive
DTL and TTL dividers with fair isolation.
However, if the output is taken to other
devices it would be well to connect these
and the time-base dividers to the oven
output through isolating gates.
The oven operates on 120 volts ac,
though proportional control would require at least pulsating dc. The oscillator
operates on 10 to 12 volts, being zenerregulated internally to 5 volts. A 20percent change in voltage causes about a
3-Hz change in the 14-MHz harmonic, so
i t is well to feed the oscillator from a
regulated power supply or, a t least, from
a stable power supply that does not feed
a varying load.
The oven is left on except during
foreign trips; no adjustment in crystal
frequency appears to be needed except
possibly once a month, or for an ARRL
frequency-measuring test in which an
error of one or two Hertz may be
undesirable.
C. & H Sales* has sold a large number
of James Knights (now CTS Knights),
oven/oscillators, 1 MHz, model JKO-PIPX96D, with proportional ovens. These
ovens also plug into octal sockets but
operate from 23 to 36 volts dc, both for
the oscillator and the oven. Varying the
voltage on the oscillator down to eight
volts controls the frequency over a considerable range. A hole plug in the top
can be unsoldered in order to reach the
frequency-adjusting capacitor.
Probably there are other oscillator/
oven sources, both surplus and new, such
as Bliley and CTS Knights. Only mercury
thermostats and proportional control will
be free of occasional clicks in a receiver.
'Monitor Products Company, 815 Fremont,
South Pasadena, California 91030.
'C& H Sales, 2176 East Colorado, Pasadena,
California 91 107.
'The SN74162N synchronous upldown decade
counter is available from Polypaks, Box 942,
South Lynnfield, Massachusetts 01940.
18
february 1972
upldown counters
Before concluding it may be desirable
to make preliminary mention of the
SN74162N synchronous upldown decade
counter, which is fully programable5 - that is, it can start counting at
any number, and even divide by odd
figures like seven. This has become available under $5 and need be used only in
decades that are displayed on the readout. *
For a year or more these devices have
provided a newer approach to decade
frequency division; like the 7490 decade
they divide the frequency, but they also
provide a down-counted read-out. There
is good reason to mention these because
of a possible simplification of equipment
by eliminating all circuitry used for
synthesis of the original signal frequency
before counting it.
reading material
Preliminary reading material on nonlinear ICs, counters and clocks will be
found in the following reference material.
references
1. R. Wilson, G3TBS, "A 24-Hour Digital
Clock," Radio Communications, April, 1971,
page 254.
2. E. W. Conklin, K6KA. "Counter Gating
Sources," ham radio, November, 1970, page 48.
3. D. Kochen, K3SVC. "Transformerless Power
Supplies," 73, September, 1971, page 14.
4. 1. M. Hoff, W6FFC. "The Mainline F S l
Secondary Frequency Standard," OST, November, 1968, page 34.
5. E. H. Conklin, KGKA, "Electronic Counter
Dials," ham radio, September, 1970, page 44.
6. H. S. Knoll, WAOGOZ, "Simplified DigitalCounter Readout," ham radio, January, 1970,
page 66.
7. 0. C. Stafford, "Electronic Digital Clock,"
ham radio, April, 1970, page 51.
8. A. A. Kelley, K4EEU. "Digital Frequency
Counter," ham radio, July, 1970, page 16.
9 . A . A . Kelley, K4EEU. "10:l Digital Frequency Scaler," ham radio, August, 1970, page
26.
10. R. M. Vaceluke, WSSEK, "Modular IC
Counter Circuits," ham radio, August, 1970,
page 63.
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1.
For 80 thru 10 meters.
k
1l i1 d 1
4
1"
,
1
I
I
'
solid-state driver
and final for
40 and 80 meters
e
I
m
A project for one
or two weekends
P
Q
5
2
- UG
0
m
features include
antiresonant traps,
c
.g
w
the circuit
g
The driver stage (fig. 1) uses an
inexpensive Motorola 2N4124, 01, which
operates as a class-B amplifier with its
base biased through a voltage-divider
to obtain approximately collector-current cutoff. With no signal applied collector current is near zero, which rninimizes current drain during key-up conditions. As a class-B amplifier, the stage
is easier to drive than if operated in
class C. The signal input from the vfo
is coupled to the base of 0 1 at low
impedance. A 100-ohm resistor in series
-
making band switching
co
unnecessary
9
9
3
20
february 1972
This two-band solid-state transmitter was
designed for use with a vfo such as the
one described in an earlier issue of ham
radio.
It operates on 40 and 80 meters,
consists of only two stages, and incorporates the best design practices for stabilization and unwanted signal suppression.
The unit is easy and inexpensive to build
and is an excellent performer. Output can
be varied from a few milliwatts to over
two watts.
with the input a t the base of 0 1 eliminates any tendency to self-oscillation,
which sometimes may occur without it.
The signal input at the base of 0 1 is not
appreciably reduced by this resistor.
Other transistors may be substituted
for 0 1 ; for example, I've used a Motorola
2N3904 with good results. No heat sink is
required for 01.
The driver tank circuit includes a
broadband toroidal inductor, L1, which is
cuit is a double pi network for each band.
Toroidal inductances are used in the pi
networks as they are self-shielding and
occupy little space. They are also easy to
make and mount in the circuit. The
output impedance of the final stage is
approximately 50 ohms. A heat sink is
required for 02.
No switching is needed to change
bands. An antiresonant trap is inserted
ahead of each pi network. On 80 meters
the trap ahead of the 40 meter pi
network is resonant a t 80 meters and
isolates the 40-meter tank from the output circuit. On 40 meters the trap ahead
of the 80-meter pi network is resonant a t
40 meters and isolates the 80-meter tank
from the output circuit. I've used traps
for this purpose since early 1968." When
changing bands, it's necessary only to
insert the transmission-line plug into the
appropriate output jack a t the rear of the
Minibox.
performance
Wlrlng of the 40-80 meter transmitter.
fixed-tuned by C1. L1 resonates on both
bands without changing the tank-circuit
capacitance. The emitter-bias resistor of
Q1 is unbypassed to provide a small
amount of degenerative feedback, which
increases driver stability. Interstage
coupling through the B+ line is reduced
by the 25 pH choke between driver and
amplifier. Added protection is provided
by the .05 p F bypass capacitor between
B+ and the chassis.
The driver output is inductively
coupled to the amplifier transistor
through L2, which is wound over L1. L2
also provides the correct impedance
match for the excitation voltage to the
amplifier.
The rig runs about 2 watts output
using a 12 V supply. The two stages
together draw about 320 mA. The voltage
drop across polarity-guardingdiode CR 1 i s
over 1 volt. The transmitter will operate
on as little as 3 volts, reducing the output
to a few milliwatts. For regular duty, a
12-volt lantern battery makes a good
power supply. A battery pack of 8 or 10
output stage
The final amplifier consists of a
2N2102 transistor, Q2, whose tank cir*They were used in 1967 in a transmitter
known m the ARP-I.
"Joe. we got any parts for t h o w 160-meter
beam rotators we were selling last year?"
C1
220 p F dipped silver mica capacitor
L1
2 4 turns No. 2 4 enamelled on
Amidon T-50-2
CR1
50 volts, 1.5 amps
L2
12 turns N o . 24 insulated over L 1
CR2
39-volt, 1 watt zener. American
Semiconductor Corp. I N 3 0 3 4 or
equivalent
fig. 1. Schematic of the 40-80 meter transmitter. Traps ahead of each output network eliminate
bandswitching.
D cells in series will also do very well. For
reduced power a 6-volt lantern battery or
a 6-volt battery pack will work well.
Although I have operated the transmitter
on 15 volts, I have not established a safe
maximum B+ voltage. + A 100pF electrol y t ic capacitor across the battery
terminals provides an ac path to ground.
A zener diode, CRl, between the
collector of Q2 and ground protects the
transmitter from spikes in excess of 36
volts. Too much voltage on the collector
will destroy the transistor. Normally the
peak rf swing on the collector will not
exceed twice the supply voltage.
construction
The transmitter is housed in a
3 x 4 x 5-inch Minibox. Components are
mounted on terminal strips for ease of
construction. The terminal strips may be
mounted either on the base of the Minibox or on an aluminum plate, which may
be inserted into the box after component
wiring is completed. I prefer the second
method, as i t simplifies component
mounting and wiring, and the unit can be
tMotorola's Semiconductor Data book lists
maximum V,b ratings o f 30 V ( 2 N 4 1 2 4 ) and
1 2 0 V ( 2 N 2 1 0 2 ) . editor.
22
february 1972
tested before inserting it into the box.
The aluminum plate is bolted to X-inch
right-angle brackets a t each end of the
Minibox.
Start construction with the angle
brackets. I used %-inch right-angle
aluminum purchased at the local hardware store. Cut two brackets about 3%
inches long and mount one a t each end of
the Minibox. Cut a piece of aluminum
3% x 4-718 inches and bolt on the
brackets in the box. Now remove this
piece with the brackets attached and use
it outside the box as the chassis on
which to mount the terminal strips and
assemble and wire all components.
The driver stage i s located a t the front
end. All components for the driver stage
except the tank circuit are mounted on a
5-lug terminal strip, center lug grounded.
The driver-stage tank is mounted on a
3-lug terminal strip in line with the 5-lug
strip. Similarly, all components for the
final except the tanks are mounted on a
5-lug terminal strip. A 3-lug strip in line
with this 5-lug strip holds the B+ line
decoupling choke and bypass capacitors.
Q1 and Q2 may be soldered directly into
the circuit, or transistor sockets may be
used with two of the socket terminals in
L3.L7,LB
1 8 turns No. 2 0 enamelled on
Amidon T-68-2
42
Motorola 2N2102 (heat sink required)
L4.L5,L6
1 3 turns N o . 20 enamelled on
Amidon T-68-2
RFCl
50 p H rf choke, Millen 34300-50
Q1
Motorola 2N4124
RFCP,RFC3 2 5 p H rf choke, Millen J-300-25
each case soldered firmly to two lugs on
the terminal strips. Placement of resistors
and capacitors on the terminal strips is
not at all critical. The use of terminal
strips assures ease of mounting and short
direct connections.
Each trap is mounted on a 3-lug
terminal strip, center lug grounded. Each
double pi-network tank i s mounted on a
4-lug terminal strip, one lug grounded.
table 1. TYDical rms signal voltages.
80 meters
output of vfo
at base of 41
output of QI
at base of 4 2
output of Q2
final output (tank)
4.0
3.0
9.2
2.7
15.0
10.0
40 meters
4.4
3.4
8.0
2.9
8.0
9.0
The two tanks with their associated traps
are positioned on either side of the
centerline toward the rear of the chassis.
After all components have been
mounted on the chassis and wiring completed, check the circuit, point to point,
for possible wiring errors. Operation of
the two stages can then be tested before
mounting the chassis in the Minibox. Use
a two-watt, 50-ohm composition resistor
as a dummy load. A sensitive swr bridge
and reflected-power meter connected be-
tween transmitter and dummy load is
most useful for checking operation. The
swr should be 1:l; there should be no
reflected power indication on the meter.
Meter deflection in the forward direction
indicates transmitter output. Those with
a vtvm and an rf probe can check rf
voltages at various points in the circuit.
Table 1 gives typical rms rf voltage
readings as measured by a Heath vtvm
and a Heath rf probe when using a 12-volt
power supply. Different transistors of the
same tvoe will often oroduce somewhat
different results.
On the front of the Minibox is the
on-off switch for the power supply and
the phono jack for the vfo line. On the
rear of the box are 3 ohono ,iacks.. one for
the output on each band and the third for
the power-supply connection. The holes
should be drilled and the switch and jacks
fitted before the completed chassis is put
back into the box. The switch and jacks,
of course, must be removed to permit
installation of the chassis.
For good results on the air be sure to
use an efficient antenna system.
reference
1. C.
E.
Galbreath, WBQBO,
Solid-State Transmitters," ham
1970, p. 36.
2. C. E. Galbreath, W 3 Q B 0 ,
Amplifier," ham radio, July,
"A VFO for
radio, August,
" V F O Buffer
1971, p. 66.
ham radio
february 1972
23
the TR-144
a transverter
for
two meters
Introducing another vhf
transmitting converter
and power amplifier
compatible with
Drake equipment a companion to
the TR-50
The TR-144 i s a two-meter version of the
TR-50 transverter described in an earlier
issue of ham radio. Like the TR-50, the
TR-144 i s compatible with Drake TR-3
equipment. Features include 350 watts
PEP input (two-tone test signal), self-contained power supply, relay switching circuits, and a high-performance mosfet
receiving converter. An Eimac 4x150 is
used in the power amplifier. Full metering of critical circuits is provided. Additionally, the screen-current meter doubles
as an rf-output indicator, which is desirable for initial tuning and on-the-air
monitoring.
packaging
The cabinet is a TR-6 unit, purchased
from Drake for $20. The chassis is made
of .047 copper-plated steel (the plating
isn't necessary; merely a preference).
Chassis measurements are 10%x 13
118 x 2 inches. The front panel, which is
secured to the chassis by the switch and
panel-light hardware, is .060 aluminum,
5% x 10% inches." Captive hardware is
pop-riveted to match mounting holes in
the TR-6 cabinet.
'Full-scale drawings of the TR-144 front panel
and chassis are available from ham radio for
$.50 and a self-addressed stamped business
envelope. editor
24
february 1972
New oscillator circuit is built on a single-side PC
board and mounted under the retaining hardware of the driver tune control.
It's the big brother of the six-meter mixer
described in the same article, which used
a 12AT7 oscillator feeding a 6360
doubler into a 6360 mixer-driver. (This
circuit was changed for the TR-144, as
shown later.) Initial bench tests of the
mixer showed an output of 1%watts with
the voltages suggested. The mixer board
requires no modification. However, some
of the coils in the ocillator and buffer
sections must be changed to accornmodate the 28-MHz heterodyning system.
Visual monitoring of the mixer output
with a scope indicated a faithful reproduction of the Drake sideband generation.
power amplifier
Much of the power and control circuitry had been designed for the TR-50
and is adaptable to the TR-144. The
power transformer provides high and low
B+ voltages, bias voltage, filament power,
and relay-switching power. A seriesphasing circuit provides the bias and relay
voltages from the multiple secondary
windings of the transformer.
The mixer (fig. 1) i s the PC transmitting converter described previou~ly.~
Based on previous experience and the
success of the TR50, I decided to stay
with the 4 x 1 5014X250B power-tetrode
family for the TR144 power amplifier. A
push-pull circuit would yeild more output
power, but limited cabinet space dictated
a single-ended power stage.
The circuit (fig. 2) is straight-forward.
Conventional vhf construction practices
should be used. The power-amplifier plate
circuit is enclosed in a 3 x 4 x 5-inch
T o p view of transverter. A double flex shaft arrangement connects front-panel control to mlxar
output-tuning capacitor.
february 1972
25
0
+ P I 0 REG
C1,C2
miniature 8.5 p F butterfly (E. F.
Johnson 189-253-5)
C3
10 PF butterfly (E. F. Johnson
160-211
..
LOCATED
L1
7 turns no. 2 0 AWG Formvar, air
wound, 3/8" dia., close spaced
L2.L3
9 turns no. 2 0 AWG Formvar. air
wound. 3/8" dia.. close spaced
L4.L5,L6
4turns no. 16 AWG tinned copper
wire. air wound, 3/8" dia.; turns
suaced one-half wire diameter
L7.U
L9
4 turns no. 16 A W G tinned copper
wire, air wound, 3/8" diameter;
turns spaced 1 wire diameter
2 turns no. 16 AWG tinned copper
wire, air wound, 3/8" diameter;
spaced 1wlre diameter
+-v
cm FOIL SIDE
OF PC B a r n
BIAS - l e v KNIT, -125V STANDBY
L10
12 turns no. 20 A W G Formvar.
close wound on &lo"-diameter slugtuned form, tapped 4 turns from
cold end
L11
2 turns no. 2 0 A W G o n cold end
Of L 1 0
L12
8 turns no. 26 Formvar on
slug-tuned form
RFC
Ohmite 2-144
Xtal
58 MHz third-overtone
114"
dia.
fig. 1. Modified two-meter transverter (from an original circuit by K l l S P I n the April 1969 isSue of
ham radio).
aluminum utility box mounted on the
chassis. Universal joints and %-inch steel
shafts connect tuning controls to the
front panel.
The grid-compartment box is made of
0.47 steel and mounted on the chassis
underside flush with the rear-chassis
panel. The 4x150 tube-socket hardware
secures the box to the chassis undersurface.
The blower i s a 15 cfm unit bracketed
to the rear chassis wall and utility box. A
TR-144 plate-circuit compartment. Output link
to antenna i s mounted directly below plate coil.
Plate-tuning capacitor i s modified with alternate rotor and stator plates removed.
one-inch-diameter hole through chassis
and grid box accepts the blower output.
The mating edges of the blower outlet
and chassis are sealed with a fillet of RTV
silicone. The grid-box cover has a rubber
gasket to inhibit air leakage.
Power- and filament-supply connections to the 4x150 are via .OOl-pF
feedthrough capacitors. Rf coupling from
the mixer link to the 4x150 grid is via an
unbypassed ceramic feedthrough (photo).
This arrangement provides excellent grid1
plate circuit isolation, and the amplifier
requires no neutralization. Should instability occur, conventional stub neutralization should stabilize the circuit.
power supply
Power for the TR-144 is supplied by a
single transformer (fig. 3).* A full-wave
rectifierlfilter provides 900 Vdc (key
down) for the amplifier B+. Twelve Vdc
for the receiving converter and relayswitching circuits are obtained from
fig. 2. Power ampiifiar circuit. Metering scheme features switching circuit t o monitor r f output.
RFC
Ohmite 2144
CR2
1N2990B (ten 33V 1 0 W zeners
in series)
4 turns no. 10 5/8 In. dia., 1 in.
long. Tap 1turn from bottom end
M
Mlcronta 0-1 mA (Radio Shack,
$2.98)
2 turns no. 12 5/8 In. dia. spaced
1 wire dia. Mount Vd inch from
cold end of L13
'The transformer is available from J. Reeves,
WASHKE, 2207 Columbus Ave., Anderson.
Indiana 46014. Ask for P&H transformer.
.001 /.IF 600 V disc from each
cathode pin t o ground screen bypass (part of ElmacSK600 socket)
link on mixer board
february 1972
27
C A P A C I ~ SAND
RESISTORS
zma, v2 WATT
fig. 3. TR-144 power s u ~ p l y .High and low voltages for all circuits am provided by a single power
transformer.
series-connected 6.3- and I V a c secondaries. Voltages for the transverter stages
are obtained from taps on the HV
secondary.
Ten series-connected zeners provide
Amplifier grid compartment. Fltament screen.
and bias voltages are supplied via feedthrough
capacitors. input from the mixer is via unb y passed ceramic feedthrough connectors
mounted on front of box.
regulated screen voltage for the 4x150.
Any combination of zeners that will
deliver 350 Vdc and dissipate 20 watts is
suitable.
metering
The TR-144 metering scheme is the
same as that used for the TR-50. Two 0-1
dc milliammeters in series with 1k-ohm
%-watt resistors monitor screen and plate
current. Shunts for the screen- and platecurrent meters (0-100 and 0-500 mA) are
respectively 10 ohms 1 watt and 2 ohms
2 watts. The screen-current meter may be
switched to indicate rf output.
Numbers on the meter scales were
removed with a typewriter eraser and
replaced with press-on transfers to indicate the desired ranoes.
., Each meter face
was sprayed with two light coats of clear
acrylic lacquer to restore gloss and secure
the transfer numbers.
switching and controls
The relay controls are identical to
those in the TR-50 (fig. 4). The 10-dB
pad, which must be used to reduce ssb
exciter output, is switched into the
system in the transmit mode.
All rf connections between the TR-3,
TR-144, and 10-dB pad are via short
lengths of RG-58lU cable and BNC connectors. The main control relay, K3, is a
110-Vac unit by Potter-Brumfield, type
KA4314-1, which is actuated by the
keying line from the TR-3. Relay K3, in
turn, actuates the Dow-Key antenna
changeover relay, K1, and the miniature
coax relay, K2 (a surplus item). Relay K2
switches the TR-3 to the 10-dB pad on
transmit. Relay timing causes no
problem, and VOX action is good.
receiving converter
The receiving converter, available from
Spectrum International,* is model DGTC
22 and features mosfet rf and mixer
stages. I t has a gain of 25 dB and is
designed for 28-32 MHz output.
The converter is mounted in a 4 x 2
118x 2%-inch Minibox. The box cover
has BNC fittings and feedthroughs for 12
Vdc and oscillator input. The feedthrough for oscillator injection is an
unbypassed type.
The converter must be modifed slightly for transverter operation. The converter oscillator was disabled and the
0.5-pF coupling capacitor removed. It
took some looking to find this capacitor
in the converter. It turned out to be
nothing more than a small loop of wire
mounted next to the coil in gate 1 of the
3N140 mixer mosfet.
Remove the cover can of this coil by
carefully unsoldering its tabs from the PC
board. Unsolder and discard the wire
loop, then resolder the shield can. Connect a 1-pF capacitor between gate 1 on
the PC board and the junction of L4, C4
on the mixer board. Interconnections
between boards are via RG-174lU coax.
This change makes the 116-MHz oscillator common to transmit and receive
'Spectrum International, Box 87C, Topsfield,
Mass. 01983.
fig. 4. Control circuits. A and B are primary control and antenna switching circuits. Circuit C
switches the TR-3 exciter between receiving converter and tho 1 0 4 6 pad during transmit mode. D is
the attenuator necessary to reduce exciter output power.
Kl
mEr
ON m3
Q
REUY
Lb $
110 VAC
X ) OUTPUT Of
~ R E CaWV
INPUT TD
lOdB m o
RI SEVCN ,W M ,14W ISR?AGUE 459E6015J
R2 SIX ECU M M . I 4 W (SPRACW 4 5 9 E i W S )
february 1972
29
functions. No further changes are required in the receiving converter.
A pair of 1N100 diodes connected
back-to-back between receiving-antenna
terminals and ground will provide frontend protection.
alignment and test
After completing the wiring shake the
chassis vigorously to remove wiring
debris. * Inspect all soldered connections
on tube sockets, tie points, and terminals.
A 5X magnifying glass is helpful here.
Often an unsoldered wire will be revealed
beneath top connections on tie points. A
toothpick is a useful device to test the
integrity of soldered connections while
inspecting the work through the glass.
I follow a standard procedure after
wiring circuits, which consists of cleaning
all soldered connections with a 50150
mixture of toluene and alcohol to remove
solder flux and grime. Next I check all
point-to-point wiring with an ohmmeter.
With all tubes removed I then check
voltages throughout the unit. (Voltages
will be slightly on the high side with
tubes removed.) These checks are worthwhile, and often a wiring error can be
detected and corrected before damage
occurs. A time-consuming and tedious
procedure - but well worth the effort!
After completing the post-wiring
checks, install the 12AT7, 6360s, and
OB2s. Solder a 50-ohm noninductive 2W
resistor between link output and ground.
Apply power and tune the oscillator and
doubler circuits for maximum output.
Turn off the TR-144 and install the
4 X 150 in its socket.
Remove the 50-ohm resistor. Apply
power and, after sufficient warmup, key
the exciter. With no drive applied, adjust
the bias pot for 50 mA of resting plate
current on the 4x150. Apply drive and
tune L10, C3 and C4 for maximum
screen-current indication, then tune plate
and load controls for maximum rf output. Plate current should be 200 mA.
Power input with the transformer I used
was 180 watts dc - power output was
108 watts as measured with a Bird Thru-
30
february 1972
line wattmeter into a Heath dummy load.
mixer output control
The TR3 tunes from 28 to 29.7 MHz.
Tuning the TR144 from the low to the
high end indicated a significant reduction
in output power. This reduction was
traced to the output circuit of the 6360
mixer. The 6360 mixer output circuit i s
not sufficiently broad to accommodate a
1.7-MHz bandwidth. To obtain maximum
output over the entire range, I added a
front-panel tuning control for C3 in the
mixer output. A Rube Goldberg lashup of
two flexible shafts from a panel bearing
mount i s shown in the photo. A machinist friend is making a miniature rightangle drive so the installation can be
improved esthetically. This control allows
the mixer output to be peaked over the
full tuning range of the exciter.
oscillator pulling
The unit was tested on the air for
about a week. A shift in frequency
between transmit and receive modes was
noted. Circuit analysis suggested only one
possibility - the 12AT7 oscillator was
pulling. Coupling between oscillator and
doubler had to be reduced.
Several changes in coil positions were
tried without success. An outboard oscillator using a 6CW4 was constructed, and
the 12AT7 was changed to a buffer
amplifier. The 6CW4 oscillator voltage is
105 Vdc regulated. Oscillator output i s
coupled to the 12AT7 with a 5-pF
capacitor. The grid resistor in the 12AT7
was changed to 1 megohm.
The oscillator was built on a piece of
scrap PC board and mounted by the
retaining hardware of the driver tune-controt panel bearing. When air tested again,
no frequency shift was observed between
transmit and receive modes. Sufficient
room is available on one corner of the
mixer board to mount the 6CW4 tube
socket, coil, and other components. The
board was bench tested and worked
perfectly.
'A small bicycle air-pump is also helpful when
cleaning a chassis. editor.
painting
Sanding with light horizontal strokes,
using finegrade emery cloth, yields a
brushed aluminum finish on the panel.
The shiny center strip was made by using
a %-inch masking tape mask. The upper
panel half i s dove gray; the lower half
equipment gray (both are Krylon colors).
Each panel half was painted with light
coats of paint and baked for 30 minutes.
Front panel lettering consists of press-on
transfers - black on the light-gray and
white on the dark-gray panel halves.
Three coats of clear acrylic lacquer spray,
baked for 30 minutes, protect the lettering.
conclusion
The TR144 completes my original
project to design and build six- and
two-meter transverters to match Drake
TR-3 equipment Switching the TR-3 rf
connector through a Waters coax switch
allows for easy selection of either six- or
two-meter output.
An auxiliary rocker switch was installed on the panel to switch the TR-3
keying line to either transverter. The
TR-144 faithfully transverts the TR-3
sideband quality, and on-theair reports
have been excellent.
It's quite satisfying to look over one's
operating position, see identical cabinets,
and be able to say, "I built it!" This is the
prime source of my enjoyment in ham
radio.
Once again I must express my thanks
for the photographic talent and equipment of Dick McGinn, WAlIMS. I'll be
happy to answer any inquiries about the
construction of this unit upon receipt of
a stamped, self-addressedenvelope.
15
MADE I N
-
U.S.A.
The -First
AM-FM
Solid-state Transceiver
For Two Meters
No longer is it necessary to choose between
AM and FM on two meters. Now you can have
both in one compact unit. Join the gang on
the new FM repeaters yet still be able to "rag
chew" with old friends either AM or FM anywhere in the two meter band.
TRANSMITTER:
m
m
m
m
Built.in VFO (Frequency convertad for stability)
AM and FM both crystal and VFO
Four transmit crystal positions (8 MHz)
12 watt input AM and FM
High level transmitter modulation on AM
Bandpass coupled transmitter requiring only final tune
and load
Three Internal transmit crystal sockets with trimmers
for netting
One transmitter crystal socket on the front panel
Deviation limiting
RECEIVER:
Double conversion
Crystal controlled first conversion
MOS FET receiver front-end
Integrated circuit limiter and discriminator for FM
Envelope detector and series gate noiu, clipper for AM
m Bu~lt.insquelch for both AM and FM
GENERAL:
Separate transmitter and receiver tuning
B u i l t - ~ n115VAC power supply
D~rectI2VDC operation for mobile or portable operation
m Opt~onal portable rechargeable snap-on battery pack
ava~lable
"S" Meter also used for transmitter tune up
M~litarystyle glass epoxy circuit boards
Anodized lettering and front panel
m Baked epoxy f i n ~ s hon the cablnet
47 transistors. 22 diodes, 1 integrated cimuit
Dimensions: 1O'h''W x 6%"H x 7'h"D
Warranty-90
Days Parts and Labor
CTR-144 is available FACTORY DIRECT
references
1. Louis E. Sevoie, K l R A K , "TR-50 Customized Six-Meter Transverter," hem radio, March,
1971, p. 12.
2. D. W. Bramer, K21SP. "Heterodyne Transmitting Mixers for Six and Two Meters." hem
radio, April, 1969, p. 8.
ham radio
including 146.94 MHz crystal
EL,
$389.95
CBMCDAFT CFMClRMV
P.0. BOX 266-GOLETA,
b-.----
CALIF. 9 3 0 1 7
Write for more information or
use CHECK-OFF
1
;
-L
february 1 9 7 2
31
third-generation
solid-state
high-frequency converter
This converter
combines ICS
with transistors
to provide optimum
rnOnObandperformance
z
LL
>
.-a
4VI
.4
9
0
u
a
Y
32
february 1972
Anyone who spends a lazy afternoon
thumbing through the past few years'
ham publications is bound to notice the
rapid advances in solid-state technology.
This is true not only of commercial
equipment but of the homegrown variety
as well. For example, a few years ago the
"in thing" was a receiver with a bipolar
transistor frontend; even with the lowimpedance problems and poor crossmodulation characteristics they presented. Today, to the knowing builder,
they are passe; design has already run the
gamut from jfet frontends through unprotected and then protected mosfet d e
signs, and new ground is being broken
using integrated circuits. How's a guy
supposed to keep up to date when things
move so fast?
A few years ago, I built a fet converter
which seemed to work pretty well.'
Shortly afterward, they introduced the
dual-gate mosfet, which put my converter
back into the Dark Ages. I went back to
FAIRCHILD
+ I 1 VOLTS
SE 8040
O
I,
IN995
12v
m
40-meter circuit values
35 turns no. 29 closewound o n CamLl.L2
bion 1534/2/1 form. L is 12pH, Q is
50. The link is 6 turns of no. 27 wire
on the cold end o f L1.
For 20-meter operation. parts values are:
L1,L2
15 turns no. 27 closewound on Cambion 1534/2/1 form. L is 2.5 p H and
Q Is 100. The link is 4 turns of no. 27
wire o n the cold end.
L3
50 turns no. 29 wire closewound on
Cambion 1534/2/1 form. L is 17 pH
and Q is 40. The link is 6 turns of no.
27 wire on the cold end.
L3
50 turns no. 29 closewound on Cambion 1534/2/1 form. L is 17 p H and
Q is 40. L 3 is shunted with a 5.6 k
resistor. The link is 3 turns no. 27
wire on the cold end.
L4
75 turns no. 37 closewound o n Cambion 1536/2/1 form. L is 30 pH and
Q is 70.
L4
20 turns no. 27 closewound o n Cambion 1534/2/1 form. L 4 has 50 pF
connected across it instead of the 82
p F used i n the 40-meter converter.
Y1
10.5 MHz.
RFC
1 m H at 35 mA.
T1
Hammond 166D20. primary: 120 V.
secondary: 20 V centertapped at 0.1
A. Note: only one half of secondary
is used.
fig. 1. Schematic diagram of the third-generation mobile converter for 40 meters. For 20-meter
operation, parallel the primary of L 3 with a 5.6k resistor and change the tuned circuits t o
appropriate values.
the drawing board and came up with a
second generation con~erter.~Then
Motorola came up with an IC doublebalanced modulator (the MC1596G)
which turned out to be a superb mixer,
and I was done in again!3
This third-generation converter, unlike
previous efforts, is a single-band converter
february 1972
33
designed to deliver optimum performance
on 40 meters for net operation during the
poor summer conditions. Low noise, high
gain and good dynamic range were all
important design requirements, as well as
the usual high-stability and imagerejection performance necessary for
smooth operation. The circuit can be
used to cover any band right up to ten
meters merely by substituting the proper
tuned circuits and crystals; a version of
the same circuit has been used a t 100
MHz with no noticeable instability.
Making such a converter bandswitching
would be quite easy.
circuit
Varactor diode tuning i s used in the rf
amplifier which uses a Fairchild FT0601
dual-gate protected mosfet. The RCA
40673 could be used as a direct substitute. The tuning i s very smooth, with no
instability of any sort, even though the
amplifier is not neutralized. I t is possible
to peak the converter on a signal anywhere in the band, but the tuned circuits
are broad enough that constant retuning
with frequency change is unnecessary.
This is a refreshing change from previous
G\V E ONE OF OUR
SPEUHL ~LEtl<oHrc
k1T2
TO
"Each k i t
missing."
34
has a
AT 'CERTAIN '"
vital
component or two
february 1972
efforts in which all circuits were deliberatel y resistance-loaded to broadband
them, which compromised the stage gain
and increased the chance of images
appearing.
XTAL QSC
i3'f-
Ll
T
A+IIM
fig. 2. Schematic of the local oscillator for the
hf converter. F o r 20-meter operation change
the 5 p F oscillator-output coupling capacitor to
2 D F and change the crystal t o 10.5 MHz along
with re-resonating the tuned circuit.
A double-balanced modulator was
used for the mixer. The Fairchild pa796,
or the Motorola MC1596G or 1496G may
all be used in the same circuit. These IC
devices make excellent mixers, with only
the sum and difference of the two input
frequencies appearing at the output. A lot
of the spurious rejection takes place in
the mixer which seems to actually refuse
to process anything other than the correct input coming from the rf amplifier.
The chance of any spurious crossproducts
appearing in the output is very low. In
fact, the output waveform is such a clean
sinusoid (at 3.5 to 4.0 MHz) that it can
be used to drive a digital frequency
counter - an instrument easily confused
by input waveforms containing more than
one frequency.
The oscillator i s an old reliable circuit,
and almost any npn high-frquency transistor can be used. I used the 2N3646 for
this unit, but the 2N706, 2N4124 or
HEPSO would work as well, and the
circuit should work right up to ten meters
even with overtone crystals.
You can use any low-power npn transistor in the series-pass regulator in the
None were available a t the time of building. The type of construction used added
to circuit stability, allowing very short
leads and solid ground connections. Nothing less than a good hot soldering iron
Overall view of the 40-meter converter board, cabinet, power supply and connecting wiring.
power supply. The design is simple, and
you can use any bridge block rectifier or
discrete diodes. The converter draws only
7.8 mA from a 12-volt supply, so the unit
could be powered by a 9-volt transistorradio battery for quite a while without
battery deterioration. If battery operation is likely, use a 100k tuning potentiometer.
construction
The converter i s built directly on a
piece of glass-epoxy printed-circuit board
using press-fit terminals where needed
and with shields and ground connections
directly soldered to the copper. This type
of construction is excellent for rf work,
eliminating the usual mess of nuts, screws
and lugs needed for grounding to an
aluminum chassis, and the time and
materials needed for printed circuitry. An
alternative would be to use the new
Circuit-Stik instant printed-circuit decals.
should be used to make all ground connections, as a cold joint anywhere could be
fatal to circuit stability.
All semiconductors are soldered directly into the circuit, using a heat sink when
soldering each lead. Keeping leads short
and eliminating the possibility of lead-tosocket capacitance assures stability without neutralizing - even on ten meters.
The general layout of the circuit board
can be easily seen in the photograph. The
layout minimizes stray capacitance and
isolates inputs from outputs; it should be
followed quite closely.
To make sure the holes in the circuit
board line up with the utility-box cover
upon which the board is mounted, the
board was mounted on the cover and all
centering holes for coils and connectors
were drilled through both; the circuit
board was then removed from the cover
while the circuitry was installed. In this
way the holes for the terminals are
february 1972
35
concealed when the final assembly is
completed.
When construction is completed, set
the varicap tuning voltage a t the potentiometer wiper a t 7 volts, tune in a signal a t
7.15 MHz, and adjust the rf amplifier,
verter has too much gain for the receiver
used, insert a resistance (1000 ohms or
more) between pins 2 and 3 of the mixer
IC. Note that the 3.5-MHz crystal oscillator will be heard when the receiver is
tuned to 7 MHz.
The 40 meter converter circuit board. Upper right section: r f amplifier. The Varlcap can be easlly
seen just t o the right of the antenna coll. The FT0601 is i n the lower left area of the Section, upside
down, w i t h the drain connected directly t o the feedthrough terminal. Upper left section: oscillator.
Lower section: mixer. The IC Is turned upside down and mounted directly b y Its terminals. Pins 2
and 3 are clipped short and soldered directly together. Note how all ground connectlons are soldercd
directly t o the copper board.
mixer, and i-f coils for maximum signal.
You're in business.
The converter input and output impedance, with the coils constructed as
is 50 ohms' When driven and
terminated in this impedance the system
gain is about 30 dB, so keep the receiver
gain low to avoid overload. If the con-
36
february 1972
references
Mike Goldstein,
VE3GFN, -Bandswitching
F E T Converter." ham radio, July, 1968.
2. Mike g old stein. VEBGFN, "second Genera
tion FET Converter." ham radio, January.
1970.
3. Roy Hejhall, K7QWR. "An Integrated-Circuit Balanced Modulator," ham radio, Septem
ber, 1970.
ham radio
feature
after
feature
after
L
feature
In addition to those pictured---there's
5 0 0 watts P.E.P. power input---digital
readout to 1 0 0 Hertz---husky rnatching 115VAC power supply/speaker
unit and external VFO as an available
accessory.
Add all of these and you have the brilliant SB-36-a beautiful experience in
operating convenience and enjoyment.
See it at your dealer---write for data sheet.
wbndm
filters for
USB and LSB.
Absolutely
no carrier
shift when
changing
sidebands!
SSB/CW TRANSCEIVER
- 11
-
,- r
-
LINEAR
SYSTEMS, INC.
220
A i m Blvd.
Watsonville, CA
95076
More Details? CHECK-OFF Page 94
february 1972
37
pre-emphasis
for
ssb
transmitters
Reducing peak-to-average
-."
E
CY
power ratio
d
g
.--
i!
"
l
results in increased
talk power
2-
- *.-a
-
i
C
-
here's an af processor
2
that gives
,m
6-9 dB improvement
in ssb rigs
38
february 1972
m
C
E
d
8
6
g
Single-sideband transmitters are usually
rated in terms of peak envelope power
(PEP). According to one authority,' the
average output power of an ssb transmitter is one-half the peak envelope
power if no distortion is present. This
statement is made on the basis that
measurements are taken when the ssb
transmitter is modulated with a standard
test signal of two equal-amplitude signals.
It can be shown that the ordinary
voice contains high-amplitude peaks that
are about 14 dB greater than the average
leveL2 Furthermore, i t is well known that
ssb transmitters are peak-power limited.
This means that an ssb linear amplifier
may be able to handle 1000 watts average
power but will begin to flat top when
peak power approaches 2 kW.
From the considerations above, it may
be inferred that many amateur ssb transmitters are not being used t o their full
capability. If the peak-to-average ratio of
the ssb transmitter output power can be
reduced, then the talk power, or articulation index, can be increased. Speech
processing circuits have been introduced
to reduce the ratio of peak-to-average
power; however if the processing scheme
introduces distortion, then the articulation index i s reduced. The best method of
speech processing, for ssb transmitters, i s
one that provides maximum increase in
talk power without distortion and subsequent flat topping.
Let's look at two popular methods of
speech processing in amateur ssb equipment: the speech compressor and speech
clipper.
let's see what i s clipped. Speech spectral
density is distributed according to fig. 1.
This curve isn't quite accurate, because
speech characteristics vary with differences in languages and with male and
compressor
The speech compressor, which i s used
in the audio circuits of the ssb transmitter, has a typical attacklrelease time
constant of 5 x low3and 5 x lo-' second.
As the ratio of these time constants is
made shorter, the compressor action approaches that of a clipper. However,
audio compressors do not affect the
peak-to-average power ratio of the ssb
transmitter; therefore we'll not discuss
them further.
FREQUENCY (Hz1
@
6dBPE9MAK
0 12 dB PER W T A V E
@ re dB PER
OCTAK
2. Results o f different pre-emphasis networks analyzed i n reference 3. Optimum performance was obtained with curve B.
fig.
FREWENCY
I
FORMAT 1
(HZ)
I
2
1 3 1
flg. 1. Proflle of speech spectral density.
clipper
A speech clipper affects the ratio of
peak-to-average power in an ssb transmitter, which is of interest here. First,
female voices; however it i s sufficiently
accurate for our purposes.
Note that spectral density is distributed
into three formants. The first formant is
dominant and lowest in frequency. This
formant includes most of the sounds in
personal voice characteristics. Such voice
power has little to do with readability in
an ssb radio circuit; it merely adds
fidelity to the transmission. Audio-frequency compressors emphasize this
speech-energy formant, which is why
they don't do much good in ssb communications systems. When clipped, the
energy envelope in formant 1 creates
strong harmonics, which create harmonic
distortion.
Formant 2 contains most of the communications intelligence, but it is of
much lower power level. Reference 3
february 1972
39
examines different types of pre-emphasis
circuits and gives optimum slopes of
audio-response curves. From fig. 2 it is
seen that the lower in frequency at which
tioning by a low-pass filter, noise was
added until the signal-to-noise ratio was
unity. The criterion for evaluating test
results was the percentage of words
HI-RL4S FILTER
-
-
4
=
k
T
RFC
1
I
I
*p
I
~ 0 3 V
P-P
LO-PASS FILTER
Zo = 1305 OHMS
IDP
VIEW
CAPACITANeES I N v F
OlUERLIISE M T E O
UNLESS
fig. 3. Pre-emphasis circuit used b y t h e author. High-and low-pass filters are those shown i n reference
4. Diodes should be matched f o r symmetrical clipping action. Inductors i n the low-pass filter are
toroids, available f r o m many surplus sources. Capacitor values are i m p o r t a n t f o r proper operation;
Correct capacitances may b e obtained b y combining standard units. Pot A 1 adjusts clipping level.
the knee of the response curve occurs, the
steeper will be the slope. Best results have
been obtained with curve B of fig. 2.
where the kneepoint is at 1.1 kHz. The
slope of this curve is 12-dB/octave.
test results
Tests were made as follows. Preemphasis was first applied to the signal,
then the signal was clipped with a
Schmitt trigger. After clipping and condi-
40
f e b r u a r y 1972
understood in the transmission. Test
results were:
1. Linear nonclipped speech - 10 percent.
2. Linear response with "infinite" clipping - 60 percent.
3. Pre-emphasis and
clipping - 90
percent.
The most interesting observation was
that no equalizer was needed after the
processor (e. g., in the receiver).
The benefits of pre-emphasis circuits
are most noticeable in af clipping. Preemphasis circuits reduce the harmonic
content in the microphone channel,
whereas rf clippers must use elaborate
filters to accomplish the same objective at
radio frequencies.
response above 2.4 kHz and attenuates
harmonics. The processor output is sufficient for most solid-state balanced
modulators.
conclusion
I have used this processor in a solidstate 10-watt mobile transceiver with
preernphasis circuit
The schematic is shown in fig. 3. The
input circuit uses a source follower for
high-impedance microphones. If you have
a low-impedance microphone, this stage
may be omitted. Two RC networks in the
input circuit shape the slope for a response of 12 dBIoctave below 1.4 kHz
(see fig. 4).
A high-pass filteP attenuates frequencies below 300 Hz. A low-noise,
high-gain amplifier (Fairchild pA749) increases the microphone signal for the
clipping diodes, a pair of 1N914s. The
degree of clipping can be controlled with
a pot a t the amplifier input (R1, fig. 3).
The diodes must be matched pairs to
obtain symmetrical clipping action.
The speech Processing unit described in this
article is included in the 10 watt transceiver
shown in this PhotograDh of the author.
OHZCD.
encouraging results. Approximately 20
dB of clipping resulted in 6-9 dB output
improvement in speech intelligibility.
Thanks are due OH1OY, who inspired
me to build this unit while a larger unit,
using rf clipping, was being developed.
But that's another story, as Kipling used
to say.
mEOUENCY
(HZ)
fig.
Speech-processor responw wlthout
A n optimum slope of 12 dB/octave
below 1.4 k H z Is obtalned with two R C
networks In the Imput circult.
4.
clipping.
A source follower
clipper to obtain the
for a low-pass filter.
shown in reference 4,
is used after the
proper impedance
This filter, also
reduces frequency
references
1. Keith Henney, Radro Engineering Handbook,
Fifth Edition, McGrawHill, N. Y., p. 1 8 6 4 .
2. Bill Sabin, WBIYH, "RF Clippers for SSB,"
QST, July, 1967, p. 13.
3. Thomas and Niederjohn, "The Intelligibility
of Filtered-Clipped Speech in Noise," Journal
of the Audio Engineering Society, Vol. 18, No.
3, 1970.
4. E d Wetherhold, W3NQN. "An Amateur A p
plication of Modern Filter Design," QST, July,
1966, p. 14.
ham radio
february 1972
41
modular receiver
for
two-meter f m
Modular construction
with inexpensive
kits produces an
easy-to-build
two-meter f m
receiver or converter
42
february 1972
Over the past few years vhf fm has moved
from the private domain of a few hardy
experimenters to an increasingly popular
mode of communications. One drawback
still exists for amateurs who wish to get
on fm: good equipment is either expensive, or as in the case of surplus gear, takes
modifications which are enough to discourage the average appliance operator
from digging in and learning what radio i s
all about. Because of these factors - expensive equipment on one hand and
apparent complexity on the other - I set
out to find a reception method that
would give the average amateur a chance
to hear what fm is really like before
making the commitment in time and
money that current equipment demands.
receiver design
Keeping in mind that the receiver must
be simple enough for an appliance operator to build and inexpensive enough so
that even an out-of-work college student
(like myself) could afford it, modular
construction was chosen as the simplest
and cheapest system on which to base a
workable receiver. The heart of this receiver (or hearts, I should say) are transistor module kits from International
Crystal which tremendously simplify construction and subsequent modifications
of the unit. The design uses an fm
broadcast receiver for i-f, detector and
audio output stages; leaving only the
fig. 2. Converter is built
minibox.
into an ordinary
front end, mixer and local oscillator
stages for the builder. If you wish, this
system can be built as a converter to be
connected t o an existing broadcast receiver or i t can be built as a complete
receiver utilizing the circuit board from
the now ubiquitous Japanese a-m/f-m
radio.
Fig. 1 shows the block diagram of the
basic modular receiver. The SAX-1 module
which is used as the front end, is a
small-signal amplifier with a sensitivity of
1 microvolt and about 10 dB gain at two
meters. The MXX-1 module, designed
specifically as a mixer, has a conversion
gain of about 6 dB and a sensitivity of
one microvolt. The local oscillator i n this
circuit i s the OX oscillator module with a
type EX crystal.
BCI
When wiring the circuit boards, the
builder will have t o select the proper coil
and capacitor combination for the tuned
circuits from several supplied. When
making this selection, bear in mind the
input and output frequencies of the
converter and the crystal frequency
needed t o produce this conversion.
Assembly of the converter section is
simple and straightforward. The circuit is
housed in a 2 x 3 x 3% inch minibox, and
suggested placement of the modules within the box is illustrated in fig. 2. The
SAX-1 module is mounted vertically at
one end of the box next to the input
jack. The OX and MXX-1 modules are
mounted horizontally with the MXX-1
closest t o the output jack.
Connections carrying rf between
modules should be made with small
shielded cable such as RG 174/U, and all
power leads should be choked t o prevent
the circuit from oscillating. The value of
resistor R1 in the B+ lead to the OX
module i s determined by the voltage used
t o power the converter and can be found
in table 1.
The selection of a crystal frequency
for the converter will depend on the
output frequency used. For the 88- to
108-MHz band, the frequency of the
crystal may be found by using the
formula fcrysral - fin - four
For output
frequencies below 88 MHz the crystal
frequency is found by using the formula
fCrystal = (fin - f,,)/2.
If outputs below
88 MHz are used, i t will be necessary t o
use the series tuned circuit L1 - C1
7RAP
FILTER
fig. 1. Block diagram of
the completa converter.
SAX-,
MXX-I
I
I
converter construction
Construction of the converter begins
with wiring the module kits. This should
present no problem t o even the beginning
builder as they are all circuit boards and
have parts placement clearly marked.
february 1972
43
table 1. S u ~ p l yvoltage vs R1.
voltage
R1
(ohms)
which is tuned to the local-oscillator
injection frequency, which is the second
harmonic of the crystal frequency. The
values of L1 and C1 will depend on the
injection frequency, and can be determined by the use of a nomograph such as
the one which appears in all recent issues
of the ARRL Handbook. For injection of
the fundamental crystal frequency, L1
and C1 may be omitted, using shielded
cable between the OX and MXX-1
modules.
In some areas, it may be necessary to
install a parallel-tuned trap filter at the
antenna input of the converter to eliminate feedthrough of local fm broadcast
stations. The filter should be tuned to the
frequency of the offending station.
Before power is applied, all tuned
circuits should be adjusted to their proper
frequencies with a grid-dip meter. Although this procedure is not absolutely
necessary, it is a good idea as it makes
alignment much simpler, and if an error
has been made in component values in a
tuned circuit, this procedure will allow
you to detect and correct i t before things
reach the hair-pulling stage. If you do not
own a grid-dip meter i t may be a good
idea to buy or build one as it i s one of the
most useful pieces of test equipment you
can have around the shack.
I f the converter is to be used as part of
a receiver rather than as an outboard
converter it is worth pointing out that
most, if not all, of the imported transistor
radios use a positive ground system; this
converter uses a negative ground. If the
receiver board has a positive ground, care
should be taken to isolate the board from
the chassis ground used for the converter.
It may be simpler to power the receiver
board with a separate battery and to leave
i t in i t s plastic case.
operation
When power is applied to the converter there will be a slight increase in
receiver background noise. If there is an
extremely high noise level and all manner
of whistles, blurps and birdies appear, or
if the converter draws more than about
35 mA, the circuit is probably oscillating.
If oscillation occurs and the power leads
have all been choked, i t will be necessary
to shield the MXX-1 module with
grounded partitions made of flashing
copper or copper-clad circuit board.
When the converter is operating properly it is aligned as follows:
1. Using a signal generator, grid-dip
oscillator or received signal, peak the
coils on the SAX-1 and MXX-1
modules for maximum audio output at
the receiver.
2. I f a tuned circuit is used between
the OX and MXX-1 modules adjust i t
for maximum audio output at the
receiver.
3. If you used a trap filter tune it for
maximum attenuation of the interfering signal.
4. All of these adjustments are slightly
interlocking, and i t may be necessary
to repeat this procedure several times
until maximum performance is obtained from the converter.
The prototype receiver, which consisted of the converter feeding a hastily
repaired GE portable receiver, performed
better than expected. Although the receiver has a wide i-f and uses a wideband
detector, the only difficulty encountered
in copying narrow-band signals was that
of adjacent-channel interference from
strong signals during crowded-bandconditions.
This design is an adequate receiver for
monitoring the local repeater. For higher
performance several modifications can be
made to the original design. The addition
of an fet preamp will provide more
sensitivity and greater overall gain. It may
also be desirable to include a second
SAX-1 module between the MXX-1
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module and the receiver if the converter
does not provide sufficient gain.
You could add a noise-operated
squelch and an improved tuning mechanism. Although the receiver can be tuned
with i t s main tuning capacitor, the designed bandspread of 20 MHz does not
lend itself to tuning easily between channels spaced 60 kHz apart. You can add a
small variable capacitor in parallel with
the main tuning capacitor to provide a
slower tuning rate over a limited range of
frequencies. Another method which may
be used is shown in fig. 3. This method
uses switch selected crystals to determine
frequency and guarantees that the receiver will always be right on frequency
and will allow the receiver to find and
monitor an inactive channel. Although I
did not try either of the above methods,
there i s no reason why they should not
work as long as you use good construction techniques and keep lead lengths
short.
Transistor modules provide an easy
way to get on fm. The flexibility provided by this method of construction
encourages experimentation and optimization of designs. The receiver design
presented in this article i s only one of
many possible ways for the amateur to
get decent performance at two meters for
reasonable cost. It is hoped that the
design presented here will not be considered a cut and dried cookbook recipe,
but rather a starting point for experimentation with various receiving techniques.
ham radio
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february 1972
45
a simple
crystal checker
with new components
makes a handy
z
S
fn
0
one-evening project
for testing
f
Q¶
2
X
0
surplus crystals
m
X
46
february 1972
Often I have wanted to check a crystal
for activity and frequency before using it
in an electronic project. Many surplus
crystals have two or three numbers on
them, any one of which could be the
crystal frequency; and it is sometimes
unknown which mark to believe. By
plugging the unkrlown crystal into the
checker described here, i t will oscillate at
its first mode, allowing me t o tune it in
on a nearby hf receiver. Also, a high
impedance voltmeter connected t o the
test point of the checker gives a dc
indication of oscillation.
The circuit of the crystal checker is
presented in fig. 1. It i s the old familiar
Pierce Oscillator, with an insulated-gate
fet substituted for the original vacuum
tube. Unlike a vacuum tube, however, an
insulated-gate fet cannot draw dc grid
current, and so D l has to be added if we
intend for the grid-leak bias system to
work. (Perhaps "gate-leak" bias system is
more correct in this case.) The diode
should be fast enough t o rectify up to 20
MHz, I suggest three devices in order of
their preference. The Hewlett-Packard HP
5082-2800 and the Motorola MBD 501
are both Schottky Barrier (or hot carrier)
types, and the Fairchild FD 700 is an
extremely fast silicon switching diode.
The MFE 3004 insulated-gate fet is
best soldered into the circuit so that i t
cannot be destroyed by static voltages
between the gate and either source or
drain. The MFE 3004 comes with a small
metal sleeve that shorts all four of i t s
leads together. Before removing this
sleeve, the circuit should be finished and
ready to receive the fet. Then wrap
several turns of fine tinned wire (one
strand pulled from a short piece of
stranded hookup wire) around the MFE
3004 leads, so as to short them all
together. Remove the metal sleeve and
solder the fet into the circuit, leaving the
shorting wire in place until finished
soldering.
The Pierce circuit is fundamentally a
form of the Colpitts oscillator, where the
crystal looks inductive, and parasitic
capacitances of the fet form the capacitive tap. This is shown in fig. 2; note that
..
,
OUTPUT
MOllXULA
MPFW
%!AIM
fig. 1. Schematic of the crystal checker. 0 1 is
explained in the text. The checker is made for
fundamantal mode operation only.
Cgd is in parallel with the crystal, and the
net reactance of the crystal and Cgd is
inductive.
The crystal checker will only work
with fundamental mode crystals in the 1to 20-MHz range. Below 2 MHz, the
impedance of the rf choke becomes too
low to allow the drain to appear to be
floating. AT-cut crystals are not generally
made for the fundamental mode above
about 20 MHz. Many surplus crystals in
rb
fig. 2. Equivalent circuit of a Pierce crystal
oscillator, showing that It is, in fact, a form of
Colpitts oscillator.
the 20-MHz range '(particularly CR9/U
and CR24lU) are third-overtone types. I f
such a crystal is used with the checker
(with appropriate pinning adapter) i t will
not oscillate as marked, but at approximately one-third that frequency. For
instance, a CR9/U crystal marked 19.825
MHz oscillated at 6.615 MHz.
As shown, the crystal checker was
built to accommodate either the FT 243 or
HCGIU styles of crystals, because these
are by far the most common. Other
crystal sockets could, of course, be
added. The checker is constructed in an
LMB-00 box chassis with the battery
terminals out one side. Since I only use
the unit occasionally, no power switch
was included; I simply connect the 15
volts for use. A Burgess U10 or Eveready
411 battery i s adequate as a 15 volt
source.
With the 15-volt battery connected,
the fet will draw Idss,which i s rated 2 to
10 m A for the MFE 3004. A highimpedance voltmeter (such as a vtvm)
measuring the voltage between ground
and test point should read about zero
before a crystal is plugged in. When the
crystal is plugged in, the voltage at the test
point should jump to some negative
voltage (- 10 volts for a good, active
crystal) indicating oscillation.
ham radio
february 1972
47
ENVIRONMENTAL PRODUCTS
UNIVERSAL
DCU/DRIVER
These universal countlng modules have heavy
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TTL used throughout. Requires 5 volt O 120mA
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Typ. count rate is 20MHz except
the NR-3H which i s 70 MHz. Will drive any
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for DVM o r over-under circuitry. The overrange
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Displays not Included. PC board is 3 % " x 6".
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NR.3FM Multi-Stage Counting Unit .............
$39.95
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STANDARD
LINE
CLOCK
SOURCE
"+"
Contains a .002% crystal oscillator wlth TTL
decade dividers to give output frequencies of
10. 1 MHz. 100. 10, 1 kHz. 100. 10. 1. & 0.1 Hz.
Kit requires 5 volt supply @ 175mA. Uses low
TC components and has zero-beat trimmer.
Great for freq meter. digital clock. etc. W/
complete fnstructions. ........................ CRO-IP $21.95
The DCC-2 derives precision gatlng and clock
signals from the 60 Hz line. The input is a
combination schmidt trigger and integrator which
eliminates false triggering from line noise. The
input is over-voltage protected and requires no
adjustment. l T L compatible output frequencies
are 10. 1. 0.1, & 0.01667 (1 pulse/min.) Hz. PC
board measures 1.2" x 3.5".
DCC-2A Line Frequency Standard . . . . . . $12.95
I
ANALOG
POWER
SUPPLY
Power your OP.AMPS with this versatile. low
cost. dual.polarity regulator. One control varies
both outputs simultaneously over the range o!
0.15V.
Electronic current limiting may be set
separately for each output over the range of
25-200mA. Regulation is 0.1 % and the ripple is
below 3mV RMS. All parts conservatively rated
for long life.
APS-5A Op-amp Power Regulator .................$12.95
TR-200 Transformer for APS-5A
LOGIC
SUPPLY
REGULATOR
-
2.95
Both kits have an output range of 3.3V t o 5V
with current limiting and short circuit shut down.
Regulation is 1% and ripple & noise is lOmV
RMS. Heavy duty components insure long life
and allow rugged use.
DPS-1A Output current 0.6A
DPS-2A Output current 2.2A
$6.95
...........
9.CI5
TRIO0 Transformer for DPS-IA
2.29
TR500 Transformer for DPS-2A
.........................5.95
More Details? CHECK-OFF Page 94
LED READOUT MODULE
-
COUNTER - LATCH
-
DRIVER
This new module has all the most desirable features
required in counting and display. Fits 18 pin connector.
5V supply. All TTL logic. 20 MHz count rate.
Miniature 7 segment display mounts in 16 pin
dual in-line socket. 5V operation at 8 mA. per
segment. 100.000 hr. life. W/decimal pt.
3015 Miniature Display
........................$3.45
3/$10.00
LARGER 7 segment display as pictured with the
NR-3 series kits. Bright numerals can be seen
even in direct sunlight. Mounts in 9 pin miniature socket supplied with the kits.
2010 7 Segment Display 0-9 DP .............................. $4.45
2020 As above except "1"
LED
.................. 3.95
RAM
Electrically and physically identical to the
popular MAN-1. Has higher light output
than MAN-1. Includes LH decimal point.
W/spec sheet & app information.
The 1101 Random Access Memory (RAM)
will store and readout 256 bits. The chip
is TTL compatible and comes with a complete spec sheet w/applications.
LED700 7 Segment LED Display ...........$7.95
(QUANTITY DISCOUNTS AVAILABLE)
1101 256 Bit RAM
Bulld several Instruments wlth thls chip and
little else. Flrst really useful LSI chip for the
experimenter. Contains:
..
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$8.95
LSI
+
Four decade counters
werrange
Four 4 bit latches w/BCD outputs
Seven segment decoder
Display multiplexing circuitry
Two programmable oscillators
Single 5 volt supply at 5mA 1 ! I
Inputs TTL compatible
Housed in 28 pin dual in-line pak
Comes with 9 p. booklet of specs & app
notes. Booklet contains interfacing info
on all seven segment displays made.
5002 LSI Chip .............................. .
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......................$26.95
5005 Booklet on 5002 only .......................... 1.50
At last1 Noncritical memory planes for the
experimenter. Made by Ampex for IBM spares.
They were removed from NEW core stacks. The
large 50 mil cores allow the use of the most
inexpensive sense amps. The cores are in an
80x50 array. All the necessary core specs are
included with each plane. Available is an 80
page booklet describing an 8 bit x 1000 word
memory using the MP-LA. Parts lists, schematics. and app notes are included in the booklet.
MP-lA 4000 Bit Core Plane
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More Details? CHECK-OFF Page 94
WE STOCK THESE
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TRANSISTORS & DIODES
POWER TRANSFORMERS
RESISTORS & CAPACITORS
PC BOARD DRILLS
WE PAY POSTAGE
317-743-1893
february 1972
a 49
calculating
the inductance
of toroids
TWO handy formulas
I
g
owned an ARRL Lightning Calculator
Type A, or a Coil Winding and L/C/F
Calculator Type A. I did not have one of
those devices, so, rather than waiting
until I could get one, I sought a formula
which could be used without any special
apparatus.
I found the eauation:
0
and a table
give quick
of the inductance
of homemade toroids
(D
.g
-.E
=
w-
*
.
B
"x
Toroid inductors, with their high Q, small
size and self-shielding properties, are excellent for use in modern solid-state
gear - especially where space is a valuable
commodity. In the past, however, there
has been one drawback: It was very
difficult to calculate how many turns i t
would take to give you a desired inductance. In a back issue of OST, there were
instructions for doing this, provided you
50
february 1972
T
0
13
i
Z
0
N
=
K
~
(I 1
Where N is the number of turns, L is the
desired inductance in microhenries and K
is a constant dependent on the toroid
being used. Table 1 lists this constant for
a number of Amidon cores in common
use. In this table, K is printed to eight
decimal places. it i s not necessary to use
all of these places, and your results will
be close even if you truncate the last 6 or
7 digits. For example, suppose you need a
I O - ~ H coil and have a T-68-2 core.
Substituting the known values into the
equation, you obtain
Since there is no such thing as a fraction
of a turn on a toroid, you should round
the answer off and use 43 turns.
If you desire to use a core other than
one of those in table 1, you can calculate
K for yourself. The formula is
K=N1
(21
T
Where N1 i s the number of turns on the
particular form you are using which gives
the inductance L1. To illustrate, suppose
table 2. Maximum number of turns of various gauge wires o n standard Amidon torold cores.
wire size
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
you have a toroid form of unknown
properties and you need a specific inductance. The first thing to do is put on a
t e s t winding and measure it's inductance.
The easiest way to do this is by
making a tuned circuit with the test coil
and a capacitor and finding the resonant
frequency with a grid-dip meter. I have
experimented with this and have found
that the best way to couple to a toroid is
by using rather long leads on the capacitor and draping the tuned circuit over the
gdo pickup coil. An alternate method i s
to make the tuned circuit with the
shortest leads possible and putting a
length of wire through the core and
shorting the ends. Coupling to the tuned
table 1. Toroid-core
equation 2.
constants
for
K
wpe
T-94-2
10.87375857
T-25-2
16.76244696
use
in
circuit is made through this pickup loop.
In any case, once the resonant frequency i s known, the inductance of the
trial winding can be calculated. Now you
are ready to use eq. 2. Simply substitute
in the now known values of N1 and L1.
In case you need it, the formula for
inductance is
L = 25330
FZC
Where F is in MHz, C i s in pF and 1 i s in
pH.
One other thing you might need to
know i s how many turns of a given size
wire you can fit on a given toroid. Table
2 gives this information for most of the
toroids in table 1. In general, use the
largest size wire you can, since this will
help to insure maximum Q. At first
glance, i t might seem that many of the
cores on table 1 are not listed in table 2.
Keep in mind that the first two numbers
in the type designation specify the size of
the core (a T-94-2 has the same physical
dimensions as a T-94-6 and will hold the
same amount of wire).
These formulas should provide the
correct answers to the nearest turn or
two - accurate enough for most amateur
work.
reference
1. "Technical Correspondence," OST, April,
1971, page 48.
ham radio
february 1972
51
" circuits and
techniques
fm deviation
measurements
In the enjoyable task of learning technical
techniques, the knowledge gained from
making tests and measurements is especially rewarding. This is particularly true
when learning the makeup of the fm
wave. In spite of this, very few amateurs
make deviation measurements, and the
carrier-zero technique of deviation measurement has been almost ignored by most
radio amateurs. It should be better
known.
A complete fm wave has a constant
amplitude and a varying frequency. It is
composed of a carrier component and a
number of sideband pairs that depend
upon the modulation index. The carrier
and sideband spectra for an fm wave of
+lo-kHz deviation and 2000-Hz modulation i s shown in fig. 1.
If the magnitude of the fm wave is to
be kept constant and at the same time contain a number of changing sideband pairs,
it is obvious that the carrier amplitude itself must vary up and down with modulation. In fact, a t certain index values the
carrier level reduces to zero. The first five
such null points are: 2.405, 5.52, 8.654,
11.792 and 14.931.
Spectra distribution for the first two
index values are given in fig. 2. A
1000-Hz modulating tone is assumed.
You can gain a practical understanding of
the technique by considering what happens when a 1000-Hz tone is applied to
the input of the fm transmitter and i t s
amplitude is increased gradually from
zero to produce higher and higher deviation levels. Obviously there is an increase
in deviation and an increase in the modulation index. If this is done gradually and
the level of the carrier only i s measured,
it is found that i t s magnitude moves up
and down. When the amplitude of the
1000-Hz notes rises to a point a t which
the modulation index is 2.045, the carrier
magnitude falls to zero. At this point the
deviation would be:
deviation = modulation index x audio
frequency
deviation = 2.405 x 1000 - k2.4 kHz
If you now continue to increase the
audio, the carrier once again rises and
falls in magnitude. When the index of
5.52 is reached, the carrier again falls to
zero. The deviation a t this carrier frequency is:
deviation = modulation index x
modulating frequency
deviation = 5.52 x 1000 = T5.52 kHz
As the magnitude of the audio frequency
fig. 1. Carrier and sideband distribution for
modulation index of 5. Modulating frequency =
2 kHz.
MOWLATICFI INDEX = 5.52
fig.
2. Spectrum distribution for first two
carrier-zero posltio.nr.
is increased the carrier will pass through a
succession of zero positions. For the fifth
carrier-zero point (using 1000-Hz modulation), transmitter deviation would be
approximately f 15 kHz.
You can use these carrier-zero points
to advantage in making carrier-deviation
checks. To use them the emission spectra
must be displayed on the screen of a
spectrum analyzer. Alternately, a frequency meter or receiver could be used if
they contain sharply tuned resonant circuits able to delineate the carrier from
the first pair of sidebands. The functional
block diagrams of fig. 3 show typical test
setups. A spectrum analyzer oermits the
display of carrier and sidebands in accordance with figs. 1 and 2. Such an oscilloscopic analyzer can be connected directly
to the i-f system of an fm receiver. More
expensive analyzers that operate in the
vhf band can be connected directly to the
transmitter output using an appropriate
dummy load.
You can make carrier-zero measurements with relatively inexpensive setups.
A vhf converter can be used to supply
signal to a high-frequency a-m receiver.
The S-meter circuit of the receiver must
be such that i t responds to carrier level
only. One of the older a-m receivers with
a sharp crystal filter is ideal; I have used
the old National NC-109 successfully. Use
a high-enough modulating frequency that
the first pair of sidebands ( 1 000 Hz and
up) does not influence the deflection of
the S-meter measuring the carrier amplitude. The S-meter reading should fall off
to zero as you tune between the carrier
and the first sideband. Remember that
you need a highly selective a-m receiver
with an S-meter that responds faithfully
to carrier level but not to modulation.
The modern single-sideband receiver cannot be used for this type of measurement
because of its S-meter system.
An accurate and highly selective frequency meter can also be used to identify
a center-frequency null. Such a frequency
meter must have sharply-tuned and highO resonant circuits to be able to delineate
between carrier and sidebands.
practical audio frequencies
In amateur and commercial fm twoway radio systems, narrow-band (+5kHz)
and wide-band (f15 kHz) deviation are
common. Many radio amateurs settle on
an in-between value of approximately
f10 kHz so their signals might be demodulated by receivers designed for
either narrow-band or wide-band demodulation. Practical tone frequencies of
1000, 1200 and 1800 Hz are attractive
for making deviation measurements. An
oscillator can be set precisely on frequency by choosing the standard tone
transmitted by WWV and a Lissajous
pattern display.
The second carrier-zero checkpoint of
5.52 in conjunction with a 1000 Hz note
I-F AM
SIGNAL
AMUZER
FM SIGNAL
RECEIVER
URRlER
5 - M E R
fig. 3.
Carrier-zero test setups.
february 1972
53
I= \
(XMS
i r ~ b
MODULE
MlCRORlONE
HEPBOI
VFO
72
fig. 4. I C phasing-type sideband generator f o r 160 meters.
can be used to determine the setting of
the deviation control needed for
f5.52-kHz deviation. If you now measure
the audio-input amplitude to the fm
transmitter you will know just how much
voice signal is needed for this amount of
deviation.
A 1200-Hz tone and the third carrierzero point is an excellent checkpoint for
determining deviation of f10 kHz.
The third carrier-zero point and
1800-Hz tone or the fourth carrier-zero
point and 1200-Hz tone can be used as
check points for indicating maximum
wide-band deviation. Corresponding calculations are:
deviation =
deviation =
deviation =
deviation =
54
5.52 x
8.654 x
8.654 x
11.792 x
1000 = f 5.52 kHz
1200 = f 10.30 kHz
1800 = k15.58 kHz
1200 = k14.15 kHz
february 1972
The carrier-zero method of measurement is especially useful in checking out
home-built fm transmitters. You can use
inexpensive equipment and make use of
one of the good old a-m receivers that
have been sitting idly around the shack.
Most importantly it gives you a better
insight into just what takes place in using
frequency modulation.
top-band sideband generator
In the August issue1 I presented a
general schematic diagram for a phasingtype single-sideband generator using two
RCA integrated circuits. I build a 160meter version of this generator using the
B&W 2Q4 audio phase-shift network
shown in fig. 4. The balanced centertapped primary and low-impedance output winding were wound on a toroid
core.
/
R4
I0k
R7
I
W
O
7
-
C1,C2
105-580 P F trimmer
T1
audio transformer. 250-1000
ohms to 8 ohms.
T2
cz/580
pi
-8
Rb
50
m
primary.
8 0 turns
no.
26
enameled, center tapped, on
Permacor
57-1541 toroid
core. Primary is 1 5 turns
no. 26 over the center-tap
I\
area of the primary winding
T3
73.5
pH
slug-tuned
coil
(J. W.
Miller 2 1 A 8 2 5 R B I )
with 12 turns no. 26 secondary wound below original
winding
0
The generator was chassis-mounted,
fig. 5, for ease of adjustment, measurement and self-education. Test instruments
were a 1000-Hz tone oscillator, audio
voltmeter (fet vom), 160-meter sideband
receiver and service-type oscilloscope.
The latter is an optional piece of test
equipment, but it is very useful and
instructive because it can display the
various sideband waveforms. I used the
1-watt audio module shown in fig. 4 for
voice testing. A transistor output transformer connected in reverse stepped up
the low impedance of the audio-module
output to the higher input impedance of
the phase-shift network.
The rf output transformer T3 was
wound on a Permacor 57-1541 toroid
core. The primary consists of 80 turns no.
26 enameled wire center-tapped while the
secondary i s 15 turns of no. 26 overlapping the center-tap area of the pri-
mary. The rf oscillator-amplifier transformer T2 is a J. W. Miller (21AB25RBI)
coil; the secondary winding consists of 12
turns no. 26 wire on the same coil form
below the original winding. The audio
transformer T1 is an output transformer
with the secondary (8 ohms) connected
to the. output of the module and the
primary (250- to 1000-ohm range) to the
audio input of the sideband generator.
A fet oscillator-amplifier stage was also
added. It operates as a crystal oscillator,
or i t will function with the crystal removed as an amplifier and isolation stage
for use with an external 160-meter vfo.
The carrier signal is applied to the two
45' rf phase-shift networks which supply
90"-related carrier components to terminals 1 and 13 of the CA3050 IC. The
combination fixed- and trimmer-capacitor
values permit proper 90' relations on the
160-meter band.
february 1972
55
tuning
A good first step is to adjust the audio
and rf phase-shift networks. The audioinput attenuator R1 is set to midposition.
Set potentiometers R3 and R 4 to midposition. An oscilloscope or audio voltmeter can be used to observe the 1000-Hz
tone a t terminals 10, 5 and 8 of the
CA3050. Place a 50-ohm carbon resistor
across the sideband-generator output.
Potentiometer R2 can then be adjusted so
the audio level a t pin 10 is the same as a t
pins 5 or 8, depending upon the position
of the sideband switch.
The objectives of the rf phase-shift
adjustments are to supply equal-level and
90°-related rf components to pins 1 and
Initially, the 50-ohm potentiometer R6 i s
set to midposition. Potentiometer R5 is
also set to midposition. Capacitor C1 is
adjusted for equal-magnitude levels across
R7 and C1. Likewise the trimmer capacitor of the C2 combination is adjusted for
equal levels across the C2 and R6 series
combination.
Keep the 50-ohm terminating resistor
across the output and connect the output
of the sideband generator to the antenna
input of the sideband receiver. Apply the
rf-carrier component only. Turn back the
rf gain-control setting or detune the
pre-selector so you do not overload the
receiver. Adjust the level for an S9 meter
reading. Open up capacitor C3 several
Photo of the ssb generator. T h e phase-shift network is the socket i n the right hand corner.
13 of CA3050. How do you determine
when a 90° phase shift occurs? Forty-five
degree networks are involved, and in
any series resistor-capacitor combination
voltages of equal value appear across the
resistor and capacitor when a 45' relationship is established. Your indicating
instrument can be an oscilloscope or rf
voltmeter that can measure up to 2 MHz.
turns away from i t s maximum setting.
Now adjust the tuning-capacitor C4 for
maximum S-meter reading.
Adjust capacitor C3 and potentiometer R 8 alternately for minimum
S-meter reading. A slight readjustment of
potentiometers R5 and R6 may help a bit
in further reducing the carrier level. Make
these readjustments carefully and be
certain that you can return them to their
initial positions if necessary.
You can also make oscilloscopic observations with a high-impedance probe.
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Jrr
fig. 5. Chassis layout for the 160-meter ssb
generator.
Since the probe attenuates the desired
signal a problem that often arises is direct
carrier pick-up by the scope lead which
can result in a false pattern display.
Apply a '1000-Hz audio tone, tune in
the modulation on the receiver and check
the upper and lower sidebands to determine which position provides the highest
ratio between the desired sideband and
the undesired sideband. This procedure
permits you to determine the position to
set your phasing sideband switch.
Throw the phasing sideband switch to
the opposite position. Also change your
receiver sideband switch to the other
position. Your dominant sideband should
now have moved from one side of the
carrier frequency to the other.
Set up the combination for operation
on lower sideband. Now tune to the
opposite sideband and adjust potentiometer R1 for minimum undesired side
band. Very slight readjustments of
potentiometers R3 and R4 as well as R 2
may aid in the reduction of the undesired-sidebandlevel.
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00
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51
1 AMP MOLDED BRIDGE RECTIFIER
-
200 Volt PIV Small Size
Manufactured By General Instrument. Ideal For P.C. Board.
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reference
1. Ed Noll, W3FOJ, "Circuits end Techniques,"
ham radio, August, 197 1. page 50.
ham radio
'm. wein~henker
!j. K 3DPJ
BOX 353. IRWIN, PA. 15642
tebook
the PIV rating the same way but I put a
colored dot on the stud for the current
rating - brown for one amp, red for two
amps, and so forth.
Paul M. Rich, WA7BPO
color coding parts
Fearing that I would drop a parts bin full
of unlabeled surplus diodes and transistors - as Poly-Paks and other bargain
assortments often come - I developed a
scheme for color coding them. For 15
cents per bottle, I bought a %-ounce jar
of quick drying enamel for each color of
the standard color code. After experimenting with expensive artist's brushes, I
selective rf ampiifiers
-
OID R E ~ I M R
fig. 1. Selective rf amplifier for 80 meters. '1
resonates to 3.5 MHZ with 36s-DF broadcast
variable. Coupling coils ( 3 turns each) are
spaced 1" from L1, not wound around it.
found that the lowly round toothpick
worked best for marking the components.
You can use a different toothpick for
each color so you don't have to clean the
brush at the end.
TO mark transistors I do not put any
mark for the 2N- prefix; I just paint on
the last digits. For a 2N706, for example,
I put three dots of color on the side of
the case - purple, black and blue (706).
For an epoxy diode with an 800 volt PIV
rating* I paint on a grey. black and brown
dot - with the grey dot at the narrow
(cathode) end. For power diodes I mark
58
february 1972
All rf amplifiers and preamplifiers are
characterized by broad bandwidth. Because of this they are easily overloaded
by static and strong signals several MHz
away from the operating frequency. The
resultant distortion products from the rf
amplifier are fed on to an inherently
broadband mixer. The i-f is supposed to
clean up the mess, but it can only
eliminate those signals that are outside of
its passband; the distorted signals within
the intermediate frequency are passed on
to the detector and audio amplifier.
The answer to this problem is more
selectivity in front of the rf stage. This
can easily be done by increasing the Q of
the input circuit and decreasing the
coupling. On 144-MHz this can be accomplished with a high-Q cavity. The cavity is
fairly selective, but has some insertion
loss, and can be built after taking a course
ANTENNA
01
(7
CJ
*
0 70 R E C E I K R
fig. 2. selective rf amplifier for vhf use. CI is
3 5 - p ~per section split stator variable with
insulated shaft (see fig. 3).
That's how easy it is to own a
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Model 404 Hand Microphone.. ................ $18'
Model 444 Desk Microphone.. ............... ,525'
Model VX-2 VOX Accessory.. ................ .$35*
'Any or all of the above accessories when purchased with
the Swan 2708, can be included for the same $20 a month.
In other words, own the 2708 and any or all of the above
accessories for a total of $20 a month. Annual percentage
rate of finance charges i s 18%.
' Gentlemen:
I
I Please send me the
I lowing accessories:
Swan 2708 for $429, and the fol-
i
$
y : ! : 1?
I
I
FREE 1972 Swan Catalog
I charge to my Swan Revolving Credit Card
. I am enclosing 10% down. II
I IJ G a r g e to my BankAmericard *
to my Master Charge =
I rl Charge
I
Master Charge Interbank =
! I3 Ship
C.O.D.
L; Check enclosed.
I
I Name
I
Call
I Address
I
I city
S t a t e - Z i p I Delivery will be made by,fastest surface shipment. Ship- I
plng charges collect. Prlces do not include local area I
SWAM
ELECTRONICS
seles tax.
I
A Subsidiary of C u b ~ cCorporation
SWAN FACTORY 1305 Airport Road Oceanslda CA 92054 (714) 757-7525
EASTERN OFFICE/ P.O. Box 2288, bcean, ~ . ~ . ' 0 7 7 1 2(20;)
,
531-4114
More
Details? CHECK-OFF Page 94
february 1972
59
in plumbing and silver soldering. The
required cavity size for six meters makes
it a nice monument to your ingenuity.
High selectivity can also be added to
c
INPUT
T
0
oscillator circuit shown in fig. 7. For 144
MHz the fet circuit in fig. 2 is doing
wonders.
Gus Gercke, KGBIJ
-
FFI
6-
6
FF3
-1
0
-
c
U
s
c
T
5
0-
FF4
s
MPUT
a -4
fig. 4. Standard divide-by-10 circuit is shown in (A). I n (6) flip-flops 1 and 3 are reverted internally
and must be Wired as shown to divide by 10.
the rf stage by introducing some regeneration, much in the same fashion as is used
in Q-multipliers. This approach will provide insertion gain instead of loss, and you
don't have to be a plumber.
An oscillator circuit that is sufficiently
stable for use as a vfo can be used as a
selective rf amplifier by simply loosely
coupling the antenna and receiver input
to the oscillator tank coil and adding a
potentiometer to drop the supply voltage
to the point where oscillation just ceases.
Gain and selectivity of this system can be
adjusted (one at the expense of the other)
by moving the two coupling coils closer
or further away from the vfo tank coil.
On 80 meters I use the modified Vackar
1
&===-L4%2:E~
DIAL
fig. 3. Tank circuit tor selective two-meter rf
amplifier. Split-stator capacitor is 35 P F per
section insulated shaft. F o r t w o meters, coil is
112 turn. 1" diameter; six-meter coil i s 2 turns.
1" diameter.
60
february 1972
using the flop-flip
A recent bargain hunt turned up some
RTL flip-flops in TO-5 cans; I bought
some to make up a logic demonstration
board for my sons to work with. Unfortunately, they could not get the moduloten minimum hardware circuit to count
by ten as it should. After checking the
patch connections I put a meter on the
flip-flops and found that some of them
were actual1y flop-flips.
With the normal RTL flip-flop connected as a binary divider (all inputs but
toggle grounded), when you initially
apply power Q should be low and h
should be high. If some of your bargains
are flop-flips the reverse is true. I got the
modulo-ten circuit to count by ten by
treating the normal Q and a outputs of
the flop-flips as though they were reversed at the pins of the IC. Fig. 4A
shows the normal circuit if a l l flip-flops
were actually flip-flops. Fig. 4B shows a
circuit where flip-flops 1 and 3 are
flop-flips. These inverted ICs are usable
in this fashion once you understand their
peculiarities.
Allan Joffe, W3KBM
Owning the FT-I01
is a very personal thing
If there ever was a personalized amateur rig, this is it . . . the jewel-like
FT-101 portable transceiver.
Hardly larger than a portable typewriter, the FT-101 packs 260 watts
PEP SSB, 180 watts CW, 80 watts AM
input power.
It even includes built-in 117 VAC and
12 VDC power supplies. A noise blanker, so essential for mobile operation.
VOX. A built-in speaker. 25 and 100
KHz calibrators. A -t5 KHz clarifier.
Break-in CW. And much, much more,
even a mike.
The compactness of the FT-I01 chassis is a marvel of electronic engineering. One look inside and you'll know
what we mean. For instance, all critical
circuitry is on customer-replaceable
PC cards. And, except for the finals
and driver, it's all solid state. A complete transceiving package, reduced
to a compact, thirty-pound wonder.
There's nothing else like it on the market. Anvwhere.
Isn't ihis the rig you
have to have?
Whether you're a
seasoned
F
amateur, or
whether you're
Y
just starting out,
the FT-101 is the
rig you've been
waiting for. And
it's here right now.
For only $559.95,
you can have it.
Owning and using
the FT-101 is a very
gratifying, very
personal thing. You
know the feeling.
-
--------------------
I
I
SPECTRONlCS EAST
lh,p!
()
lHo> 14-,-,
\ I , ~ V , ()Iu<t
1.122.l I [2lf>mcl!i . l ? < ~ -
M o r e Deatails? CHECK-OFF Page 94
U Please send detailed information on all Yaesu
products.
I
I
II
I
1 Name
I
Address
II
I city
S t a t e Z i p
I
All prices F.O.B.Signal Hill. Ca.
I
Master Charge and Banklrnericard accepted. "H6"
I
--------------------
i
SPECTRONlCS WEST
rn
~
Enclosed find I
Please send model(s)
1
february 1972
61
ic keyers
The Memory-Matic 500 and the
Space-Matic 21 are two new electronic
keyers from Data Engineering. They were
developed especially to meet the demands
of professional and amateur code operators. These keyers were designed to send
all code elements: dot, dash, dot space,
dash space, character space and word
space in an instant-start, self-completing
mode with a guarantee of no missed or
extra dots or dashes and provides jamproof dot, dash, character and word
spacing. Each code element is automatically generated with little or no
effort on the part of the operator.
The memory system included with
each Memory-Matic 500 provides the
serious DX, contest or traffic operator
with provision for instant storage of code
characters or messages, for an immediate
reply to on-the-air contacts.
62
february 1972
Messages of approximately 40 code
characters are easily keyed into the
memory for calling stations, giving a
contest exchange, calling CQ or testing.
Loading code characters into memory or
transmitting messages from memory is
accomplished a t the same speed and
weighting ratio in use by the operator.
The memory allows continuous transmission on a repetitious basis of any
message in storage.
Iambic squeeze keying is provided
through the use of twin paddles. Iambic
operation provides alternate dots and
dashes when both paddles are squeezed.
Advanced dot-dash memories automatically insert a dot in a series of dashes
or a dash in a series of dots and insures
against missed or extra dots or dashes.
Jam-proof spacing is provided for dots,
dashes, characters and words. Dot and
dash spacing i s automatically added following each dot or dash. Character spacing is automatically added following the
last dotldash element which make up
each character. Word spacing is automatically added following the last character which makes up each word.
A 500-bit instant-load memory is provided in the Memory-Matic 500 which
can be programmed or updated by
moving the function switch to rnemoryload and keying any message into
memory. When 50 storage positions remain in memory the monitors's sidetone
pitch automatically increases, indicating
to the operator that the memory is
near-full. The monitor will emit a steady
sidetone if the memory overflows; this
condition necessitates reprogramming of
the memory-load sequence. Once a message is entered into memory it can be
transmitted manually or automatically a t
intervals ranging from a fraction of a
second to several minutes. Adjustment of
the automatic transmission interval is
accomplished by a rear panel control.
Both the Memory-Matic 500 with the
500.bit memory and the Space-Matic 21
without the memory feature have a speed
range of 5 to 85 words per minute with
adjustable weighting, independent of
speed. They have provision for keying
More Details? CHECK-OFF Page 94
with a regular straight key and keyer
activation by either a single or dual
paddle key. Tune switch, variable pitch
sidetone oscillator, 117-Vac power
supply, and off-the-air self-testing circuitry are built into both keyers.
The units come with instructions, all
cables and connectors and are guaranteed
for a year. The Memory-Matic 500 costs
$198.50 and the Space-Matic 21 is
589.50. Use check-off on page 94 for
more information or write directly to
Data Engineering, Inc., Box 1245, Springfield, Virginia 22151.
veroboards
f
YOU
ASKED/
FOR IT!
HERE IT IS! . . . one complete U.S.
--
Over 285,000 QTHs
i n the U.S. edition
-
-.
\.l b ~
,.!"
ca
I:. .
-
--
-.
...
..-....
.-
.-
More Details? CHECK-OFF Page 94
-p<~--
$895
-
vqfl
_C-
:=7
..... ---- .
The Vero method of construction does
away with the etching, drilling, and tools
usually associated with breadboarding. A
perforated board has a series of parallel
conductor paths connecting all the holes
in one column. After inserting component leads in appropriate holes, a
scriber is used to break the conductor
paths where they are not needed. Where
paths are needed but are not provided by
the foil, the component leads may be
used, jumpers inserted or special pins
inserted in the holes for tie points.
Vero offers an introductory BK-6
Vero-board kit designed for experimenting with discreet components.
The BK-6 Kit consists of six Veroboards, two with a 0.2 x 0.2-inch matrix
and four with a 0.1 56 x 0.1-inch matrix,
both having a 0.052 diameter hole. The
Vero BK-6 Kit sells for $5.95.
Vero also offers the new MC-10 kit for
dual in-line integrated circuits. ICs can be
plugged in anywhere on the 0.1 x 0.1-in.
drilled matrix.
Callbook
and one complete DX Callbook per year and no
change in price. In addition you can keep your CALLBOOKS up-to-datethrough a subscription to the new
Service Edition Series published each March 1,
June 1 and September 1 -each one covering new
licenses and all activity during the preceding quarter. Annual subscription to complete Winter CALLBOOKS plus 3 Service Editions only $14.95 postpaid
for the U.S. and $11.45 postpaid for the DX.
/ I
-
mn -T-\
=s\lb+
*g;.
-
/
1
-
.
I
.
Over 180,000 QTHs
in the OX edition
$695
I
*
h
.*
::-I---.. -- -.
,:-
-4
These valuable EXTRA features included in both editions!
QSL Managers Around
Prefixes by Couotries!
the World!
Zips on all QTHs!
Census of Radio
Amateurs throughout
~i~~~i~honetic
the world!
Rado
i Amateurs' Licemse Where 'q!
Class!
Great Circle Bearings!
World PrefixMap!
InternationalPostal
International Radio
Information!
Amateur Prefixes
Plus much more!
See your favorite dealer or order direct (add 25C for
mailing in U.S., Possessions & Canada. Elsewhere add
YEARS OF SERV
RADIO AMATEU
925 Sherwood Driv
I
..
-
A Pol.* Pah .xcIuSIveI Two dlUonnt hpe.. Both
c o m ~ a t l h l s Wlth
9117446
SN74?7.
5.7448
5117475. 5 N 7 4 9 0 and 5 ~ 7 k 1 9 2I C s. Both r l t i
decimal.. 0 to 9 numorals and 1 0 lottan. Wlth
specs & hoohupa.
.
16-PIN MICRO MINIATURE
Tits Into 1 6 Din dual In 118ah.t.
LIlo: 2 5 0 000
h w n . D.lircr*
700-11. Lamhert. hrlt.ne*.
Llth
5 volts 8 mils mr seumnt. Chrractmr. . 3 6 2 " M. r
.1
-9-7." w.
. .
U 9-PIN TUBE TYPE
L
For 0rlnt.d clreult hoard or soch*L LIfor 100.000
h w r s . Delivers 6 . 0 0 0 - n . L.mb.rts wlth S volts
2 3 mils oer u = m m t . Charmcters .47" H. 1 . 2 0 " W.
LIGHT EMITTING DIODES
I Mwro mlnl. a.i.1
lead
1 . 8 8 2 for 1 1 . 4 s
I Jumho. 1 0 - 1 8 . Ileads rod 1 . 0 0 2
for
1.75
BRAND NEW! LINEAR IC AMPS
Buy an.* 3
- Take
1 0 % Dlscount
'ryp,.
ll#.~#'r,pl,'>,>
U 7 0 3 RC-IF. 1 4 hookuos. TO-S . .S1.19
7 0 % 0wratlon.l
Amp
l
59
II1710C DIUorrntl.1 Amp***
:59
O 7 1 1 C Memory. Sense. Amp***
.59
7 2 3 n volt.re ~ c . u ~ a t w(DIP)
1.49
I7 T V R - 2 0 0 0 Hi.powcr 7 2 3 ( D I P ) 1 5 9
CI 7 4 1 C Freq. Comp. 7099.. . .
:95
r_l 7 4 8 C Freq. Adiustahlr 7 4 1 * * * .
.95
L1 7 0 9 - 7 0 9 Oual 7 0 9 ' s ( D I P ) . . . 1.49
L1 7 4 1 - 7 4 1 Dual 741'. ( D I P )
1.98
D 7 4 9 . 7 4 9 S t e n o Preamp ( D I P 1 1.98
.
. . . ..
.
..
u
u
*.b'
i
**'
(mC'd
t
new callbook
. . ..
"AMATEUR" 400 MC NPN
HI-POWER TRANSISTOR
fl &I, $2.95 Bur 3 - Taho 1 0 %
.
T O - 6 0 c a m . S#mil.r to 2113632
4 0 0 me,
3 .mom. 6 0 hrcho. 1 0 0 hfe 2 3 watt..
NATIONAL LM-565
PHASE LOCK LOOP I C v s m &
1
Only
$4.95
[
1
Du.1
In Ltm
o
ro-s
c..~
4%'
-
T>I,~
~ u n crollu
C ] SN7400N W d 2 anput NAND n a b
[I SN7401N S N 7 4 0 0 -4th open c o l l u t
U SN7402N 0u.d Io n ~ NOR
t
=at.
[J SN7404N He. 1nr.rt.r
il SN740SN H e x 1nv.rttr. open coll.ct
~ ~ 7 4 T~IDI.
1 0 ~3 anwe nrno 11
..
SN7410N Dual 4 enput NANO uat*
SN7430N 8 Inout NANO gat*
[1 SN7440N Dual 4 ~ n p u tNAND buff.,
SN7441N BCD to 0erlm.l driver
U 5 N 7 4 4 6 N BCO l o 7 s - 1 d w l d r " * r
s N 7 4 4 7 N BCD to 7 u~ dcr 1drlr.r
5 ~ 7 4 7 3DU.I
~
m m..tcr
~ I O - ~ W
0 511747411 Dual D haggcnd flbo no0
~ ~ 7 4 0u.d
7 5 h,.t.h~c
~
latch
O SN7476N 5 N 7 4 7 3 . r l t h -set.*
Cloar
SN7481N 1 6 hot memor). ( u r a t c h madl
n 5 N 7 4 8 3 N 4 hlt h l n a n full add.,
u
n
u
n
n
.I.~.
I I 5 N 7 4 1 9 2 N Bi-dlnctlm.1 covnhr
~ ~ 7 4 1 9 3 ~ U O . ~ O count..
W ~
n
3.45
3.45
1 s t CATALOG on 1 1 b e r O p t ~ i s ' I C s ' , Seml's. Partr
64
febtuary 1972
The kit contains a single sided 18-inch
long Veroboard with 34 copper strips on
0.1 centers, a plug-in single-sided board
with 32 plated contacts, a double-sided
plug-in board with strips at right angles
and an epoxy glass plain board pierced at
0.1 centers with 0.052 holes. There are
also 500 terminal pins to fit the 0.052
diameter holes in a 0.1 plain Veroboard, a
pin insertion tool, a spot face cutter to
break the copper strip where required, a
0.1 reproducible design sheet and a 32
contact 0.1 edge connector. The Vero
MC-10 Kit sells for $29.95.
For more information write to Vero
Electronics, Inc., 171 Bridge Road, Hauppague, New York 11787 or use check-off
on page 94.
Marking it's fiftieth anniversary, the
Radio Amateur Callbook Magazine is
changing to a new format of one major
edition per year. This first of the new
Callbooks will be the Winter 1971-72
issue, published on December first.
A "new information service," in Callbook form, consisting of new licenses,
silent keys, call letter and address changes
for the preceding three months, will be
initiated on a qzarterly basis - every
March 1, June 1 and September 1 - to
those who have purchased the previous
December issue. This information service
will be available by subscription only,
through the order form printed in the
December edition. The price for this
service will be $6.00 per year for the
United States series, and $4.50 per year
for the foreign series. The subscription is
on a consecutive, annual basis only.
The Winter U. S. Callbook and three
supplements will cost $15.20 per year,
and the Foreign Callbook and supplements will cost $11.70. The U. s. Callbook alone will remain a t $8.95; the
Foreign Callbook is $6.95.
For more information use check-off
on page 94 or write to the Radio
Amateur Callbook Magazine, 925 Sherwood Drive, Lake Bluff, Illinois 60044.
More Details? CHECK-OFF Page 94
1
Now,,,professional a
Heathkit
instrumentation at amateur prices
Keep your rig operating
at peak performance
with these new
Heathkit budget-minders.
New Heathkit
5" Triggered Sweep Scope..
New Heathkit
Digital Multimeter..
DC-10 MHz response -Triggered
Sweep
50 ns sweep rate with magnification
AC-DC coupling
.
3% digits for 100 uV resolution on
200 mV range, 1 uV on 1000V
Furnished DC calibrator gives 0.2%
accuracy VDC (can be lab calibrated
to 0.1 %)
Here's a true digital multimeter (circuitry and readout) at far less than you'd pay for comparable
wired units. and accuracy that's better than
many wired DMMs. The IM-102 accurately measures AC & DC voltages, currents, and resistance
with no need to change probes or switch meter
for changes i n DC polarity. Five overlapping
ranges measure voltage from 100 uV to lOOOV on
DC (either polarity); 5 ranges cover 100 uV to 500
V on AC; 10 ranges measure 100 nA to 2A on AC
or DC; and 6 ranges measure resistance from 0.1
ohm to 20 megohms. Input impedance is approx.
1000 megohms on 2V range, 10 megs on higher
ranges, with overload protection built-in. Decimal
point automatically placed with range selection.
Front panel light indicates overrange. DC calibrator furnished. An internal circuit and unique transfer method allow accurate ACV calibration.
Solid-state design with cold cathode readout tubes
and memory circuit assure stable, non-blinking
operation. Kit includes standard banana jack connectors complete with test leads. Put i t together
i n about 15 hours for a lifetime of precision performance.
..
Kit IM-102,9 Ibs.
.....................229.95*
More Details? CHECK-OFF Page 94
.
Maximum flexibility in a general purpose scope, at
a price to fit any budget.. .the new Heathkit 10103 is a radio amateur's dream come true! Big
6x10 cm screen with lighted graticule for easy,
accurate measurements. DC-10 MHz f3 dB response with less than 50 ns rise time on vertical
channel. Horizontal expansion gives x2 magnification 5 % for a 50 ns/cm sweep rate. Triggered
sweep, too, with selection of either normal or automatic modes. Other features are switch controlled AC-DC coupling; provision for external
triggering signals and horizontal deflection signal;
front-mounted connectors for vertical inputs and
1V peak-to-peak signal for checking calibration;
120/240 VAC operation. Put this budget-minder to
work in your ham shack now.
Kit 10-103,37 Ibs. .....................229.9St
...
-----------------.
HEATH COMPANY. O I P t 122.2
Benton Harbor, Michigan 49022
Enclosed is $
Please send rnodel(s)
Please send FREE Heathkit Catalog.
I
i
I
-I
, plus shipping.
I
I
I
I
I
I Name
I Address
I
I
I
I
I
I
!
I
;
Prlces & specifications subject to change without notice.
'Mail order prices; F.O.B. factory.
AM-262 I
L,,,,,,,,,,-,------------------l
february 1972
65
MEMORY-MATIC 500 KEYER
FREQUENCY MARKER STANDARD
Today's newest and most advanced keyer. 500
bit/40 character Read-Write memory. Stores any
message instantly. Near-Full and overload alarms.
Includes all Space-Matic 21 features.
Markers at 5. 10. 25. 50, 100. 200 and 400 kHz.
400 kHz c stal No unwanted markers. Latest
~ " f f e r e d osc. and output.
low power
6'
-~.-
I&.
$32.95 (Less Batteries)
$198.50
\I..
....
Y
I
SPACE-MATIC 2 1 KEYER
1
ELECTRONIC FEATHER TOUCH KEY
Instant self-starting, self.completing dots, dashes,
and associated dot. dash, character and word
spacing. Adjustable we~ghting. 3.5-85 wpm. Built.
in sidetone and speaker. Iambic. Dot and dash
memories. Suitable for use with all standard keys.
The solid-state design detects the mere touch 01
your finger and eliminates such problems as
contact bounce, proper adjustments and dirty
contacts. Weighted.
$19.95, $22.95 SPOT Switch Option
$89.50
5-year guarantees
PPD USA
Send for brochures
DATA ENGINEERING INCORPORATED
BOX 1245
SPRINGFIELD, VA. 22151
DON'T BE LEFT OUT!
Join the 34,000 others who
are already taking advantage of
these great savings.
.
HAM RADIO Greenville, N. H. 03048
ONE YEAR
THREE YEARS
. . . . . . . . . . $6.00
.
.
.
.
.
.
.
.
. $12.00
Bill me later
Check or Money Order enclosed
- get an extra issue free
Name..................................................................................................................................
Address...............................................................................................................................
City........................................... State............................
66
february 1972
Zip...................................
More Details? CHECK-OFF Page 94
E& E guides hams through
radio's mysteries.
Highly popular Editors and Engineers books
from Sams give amateurs everything they need
to know about radio operation and technology.
They're authoritative, clear and easy to follow.
You'll want them for your library.
73 DIPOLE AND LONG-WIRE ANTENNAS
BY Edward M. Noll, W3FQJ
Deta~ledconstruction data lor 73 dinerent types of wlre
antennas. Appendices describe construction of noise
bridges, line tuners, data on measuring resonant frequency, velocity factor. and SWR. No. 24006-54.50
73 VERTICAL, BEAM,
AND TRIANGLE ANTENNAS
By Edward M. Noll, W3FQJ
Design and construction of 73 different antennas used
by amateurs, each built and air-tested by the author.
Also construct~onof noise bridges and transmission-line
tuners. measurement methods. No. 24021-44.95
ELECTRONICS FOR THE AMATEUR
By Louis M. Dezettel, WSREZ
Famous E&E RADIO HANDBOOK-18th
By William I. Orr, WGSAI
Edition
Covers radio-wave propagallon as it applies to amateur
band frequencies, reception and transmission pertaining
to ham equlpment, and the speclal fteld o l antennas and
how to feed them. Gives you everything needed to pass
the theory secttons of the FCC exams No. 24022-57.95
The completely updated electronics industry standard for
s
advanced amateurs. Shows
engineers, l e c h n ~ c ~ a nand
how to d e s ~ g nand build all types of radiocommunicalions equipment. Includes ssb design and equipment.
RTTY circuits, latest semiconductor circuits, IC's, speclal circuitry No. 24020-513.50
SINGLE SIDEBAND: THEORY & PRACTICE
By Harry D. Hooton. WGTYH
A b a s ~ ctext, covering origin of ssb, derivation of signals.
s~debandselection, ssb generators, carrier-suppression
techn~ques, carrier generators, speech amplifiers and
frlters, balanced mixers and converters. low-power ssb
transmitters, linear 1-1 power amplifiers, much more.
388 pgs.. hard cover. No. 24014-56.95
SEMICONDUCTOR AMATEUR PROJECTS
By Louis M. Dezettel, WSREZ
For the ham who still takes pride In using hls hands and
head, here are projects for 16 useful, money-saving accessories, uslng easy-to-build semiconductor circuitry
Units are for measuring equlpment, adding power and
convenience, converters, etc. No. 24025-54.95
AMATEUR RADIO INCENTIVE
LICENSING STUDY GUIDE
By Robert M. Brown, K2ZSQ
and Tom Kneitel, K2AES
Invaluable a ~ dlor the amateur llcense applicant Clear.
lullv deta~led.comolete. No. 24004-53.25
RADIO AMATEUR'S
F-M REPEATER HANDBOOK
By Ken W. Sessions, Jr., KGMVH
The deflnittve work on amateur I-m repeaters. Includes:
Prepar~ngand obtain~ngsites for repeaters; How to build
a repeater; Repeater appl~cations; an f-m repeater directory. No. 24008-56.95
AMATEUR TESTS AND MEASUREMENTS
By Louis M. Dezettel, WSREZ
Shows how to accomplish virtually all performance tests
on amateur transmitters, receivers and antennas . . and
how l o make required adjustments. No. 24007-$5.50
HAM AND CB ANTENNA DIMENSION CHARTS
By Edward M. Noll, W3FQJ
Tabulates d~mensiondata In feet and inches for all popular antenna configurat~ons W ~ t hthem. an antenna can
be d ~ m e n s ~ o n efor
d a specillc frequency range according to license class and mode of operation. No. 24023
-51.95
order today from
SOLID-STATE QRP PROJECTS
By Edward M. Noll, W3FQJ
By bullding ORP equipment you learn solid-state technology, slnce these rigs Include transistors a n d l o r
integrated circuits The low-cost units described have
power ratings from less than 100 milliwalts up to about
20 watts. Both cw and phone rigs are included. No. 24024
-54.25
More Details?CHECK-OFF Page 94
BOOKS
Greenville, New Hampshire 03048
f e b r u a r y 1972
67
FOR THE MAN WHO TAKES CW SERIOUSLY.
READ THE QST WRITEUP ON THE KB-1 I N THE AUGUST.
1970 ISSUE. THEN SEND FOR OUR ILLUSTRATED BROCHURE ON THE KE-1.
TO ORDER. SEE YOUR AMATEUR EQUIPMENT DEALER.
OR ORDER DIRECT FROM FACTORY. YOU MAY USE
YOUR MASTERCHARGE OR BANKAMERICARD.
SIMPLY
GIVE US YOUR ACCOUNT NUMBER.
YOUR CW SENDING DESERVES T H E BEST
ORDER YOUR KB-1 NOW!
68
february 1972
P~CKER~NG
RADIO CO.
Post Office Box 244
Portsmouth, R.1. 02871
More Details? CHECK-OFF Page 9 4
Complete packaged Multi-Band Antenna Systems employing the famous Bassett Sealed
Resonators and a special Balun. Air has been evacuated from both and replaced with pure
helium at one atmosphere.
Highly efficient system packages including all hardware, insulation, coax cable, and coppenveld
elements assembled at the factory. Complete installation instructions included.
Multi-frequency models available for all amateur bands and for commercial use, point to point,
ground to air, military and government.
MODEL DGA-4075
-$59.50
A complete system package for primary
use in the 40 and 75 meter bands at
power levels up to 4KW-PEP with
secondary operation in other bands at
reduced power levels.
MODEL DGA-152040
-$79.50
A complete system package for primary
use in the 15, 20, and 40 meter bands
at power levels up to 4KW-PEP with
secondary operation in other bands at
reduced power levels.
MODEL DGA-2040
-$59.50
A complete system package for primary
use in the 20and 4 0 meter bands at
power levels up to 4KW-PEP with
secondary operation in other bands
at reduced power levels.
MODEL DGA-204075
-$79.50
A complete system package for primary
use in the 20,40, and 75 meter bands
at power levels up to 4KW-PEP with
secondary operation in other bands at
reduced power levels.
CONTACT YOUR DISTRIBUTOR OR WRITE FOR DATA
Savoy Electronics,lnc.
P.O. Box 7127- Fort LauderdaIe. Florida -33304
•
TeI: 306-668-8416 or 306-847-1181
More Details? CHECK-OFF Page 94
february 1972
69
2 - M CLASS "C" AMPLIFIER
i
---
r"-
MODEL FM-3-30
1TO 3.5 W A r r S INPUT GIVES
17 TO 30 WAlTS OUTPUT
SIZE
ONLY
TYPICALLY 20 WAlTS OUT FOR 1 I N
AUTOMATIC T/R SWITCHING
7n x 5" x 3"
Model FM-3-30 $89.95
13.5 V.D.C.
MOBILE OPERATION
ONLY HIGH QUALITY AMERICAN PARTS USED IN ALL MODELS
MODEL FM-25
MODEL FM-7
13.5 V.D.C.
I TO 3.5 WATTS INPUT
4 TO 12 WATTS OUTPUT
AUTOMATIC T/R SWITCHING
SIZE: 5%"r3"x2%'r
13.5 V.D.C.
4 TO 12 WATTS INPUT
30 WAiTS OUTPUT
~
~
Only $49.95
~ ~ ~ ~ C 2 ~
SIZE: 5 % " r 3 " ~ 2 ~ h "
MODEL FM-10-50 F L A S H !
NOWA vailable
13.5 V.D.C.
4 TO I:!WATTS INPUT
20 TO 5 0 W A ~ OUTPUT
S
AUTOMATIC
T/R ~ SWITCHING
~ R U T S
~ C ~ ~
SIZE: 7 " ~ 5 ' ~ x 3 "
Only $69.95
MODEL FM-1-40
35
~ W
, A"n S OUT FOR TR22
OR EQUIVALENT.
Only $119.95
Only $119.95
-
Also available - 2M Preamps - 12 V.O.C. Operation
13 dB Gain - 3.5 db Noise - 2" x 21/21!
No Case - Morfel with Diode Protection - G-10 Glass Solder Dipped Circuit Board - with Instructions
$12.95
90 DAY PARTS AND LABOR WARRANTY ON ALL PRODUCTS
SEND CHECK OR MONEY ORDER TO: (Dealer inquiries invited)
Limited t i m e only - a 2 meter pre-amp free with purchase o f any of our amplifiers.
v hf
SPECIALISTS/
PO BOX 167 VIENNA VA 22180
WE WILL SHIP UPS POSTPAID ON CASH ORDERS
STUD NUT
-
THE NEW
unitized fastener for r a p i d a n d convenient
mounting o f threaded-dud. solid-state devices.
5:A if
C.O.D. ORDERS ACCEPTED WITH 25% DEPOSIT
GEM-QUAD FIBRE - GLASS
ANTENNA FOR 10. 15. and 20 METERS.
\\ //
''
r*
f 107.00
Two Elements
Extra Elements
$60.00 ea.
Submit Payment with Order
Shipped Freight collect.
Price includes
Canadian Federal Sales Tax
o r U.S. Customs Duty.
KIT COMPLETE WITH
SPIDER
ARMS
WIRE
BALUN KIT
BOOM WHERE NEEDED
SEE OUR FULL PACE IN MAY ISSUE
Replaces 5 separate items of hardware ww required for
mounting SCR's, Zeners, D~oder and Power Transistors.
PROVIDES
- insulation
Exact stud centering for maximum voltage
- Stud isolation from mounting surface
- Locking action
- Electrical connection to device stud
Rated to 30 Amperes, continuous.
Mounted with sld.
7/16'r hex-nut driver.
Supplied with Mica washer for COMPLETE mounting kit
for #lo-32 threaded stud devices.
Package of 4 STUD-NUTS & WASHERS 51.00
Package of 24 STUD-NUTS & WASHERS 55.00
-
Buy two elements now
-
Enjoy optimum forward gain on DX, with a
maximum back to front ratio and mcellenf aide
discrimination.
Get a
weight,
maximum .rtructural ntrength w i t h
am.
w i n g our "Tridetic"
70
P. O. BOX 999, ~ i ~ h tN.~J. t 08520
~ ~ ~ ,
february 1972
low
MANITOBA DESIGN INSTITUTE
AWARD WINNER
-
SCF Gorp.
a third and fourth mow
be added later with little efort.
C.nm
v.S.
41.n P.1.ntPat.ntNo.No.
3532315
794506
20 Burnett Avenue. \Vinnepeg 16. Manitoba. Canada
More
Details?
CHECK-OFF Page 94
THE STRONG, SILENT ONE.
..
IS NOW EVEN GREATER!
8877 / 3CX1500A7 air-cooled ceramic triode. Eimac's new tube is the
finest available a t any price; delivers even more power output
with less drive!
Ultra-rugged vacuum relays previously optional at extra cost for commercial
applications are now standard on every ALPM S ~ E N P Y
.
A really '%ool" kilowatt! You can run it key-down continuously for a
month at a full kilowatt d-c input-or at 2.5 kilowatts PEP with
a two-tone or voice SSB signal-and the ALPHA SEVENTY
will stay literally cool. But you'd better have a mighty husky
dummy load!
Every performance, convenience, and ruggedness feature that put the
ALPHA SEVENTY in a class by itself among high powered
linear amplifiers!
You must see the A b P M SEVENTY in operation to believe it!
Air cooled model PA77-A, $1695
D EHRHORN TECHNOLOGICAL OPERATIONS, INC.
Brooksville, Florida 33512
MODEL TT-179/FG Mfg. by Kleinschmidt.
This unit is used for printing on and
punching tape. Also for transmitting a
prepared tape when used with Model
radar beacon by
Only
$77.50
PPo
SA
I
GATEWAY
ELECTRONICS
WE HAVE MOVED TO LARGER QUARTERS
NEW LOCATION
8123 PAGE BLVD., ST. LOUIS, MO. 63130
NEW PHONE NO. 427-6116
-
Self complet~ngdots and dashes.
Dot memory for easy keying.
Precision feather-touch key built-in.
Sidetone oscillator and speaker built-in.
Relay output keys 3 0 0 - V @ 100-ma.
Keyed time base. Instant start.
5 - 5 0 wpm. Perfect dot-dash ratio.
Send QSL or postcard for free brochure.
6.5 DB GAIN VERTICAL BASE station
antenna 140.160 mhz. Manf. by Antenna
Eng. Co. 4 Ib.
$23.95
base for above 3 Ib.
$5.95
4.5 DB GAIN VERTICAL MOBILE antenna
140-160 mhz. 3 Ib.
$15.95
7200 VOLT C.T. PLATE TRANSFORMER 1
AMP - 115 or 220 volt Pri. 11" x 11" x
13". 100 Ib.
$30.00
811A TUBES - NEW. 1 Ib.
$4.95
6146A TUBES
- NEW. 1 Ib.
-
$3.75
Writs us tor your IC needs.
Stop in and see us when you're in St. Louis.
72
f e b r u a r y 1972
More Details? CHECK-OFF Page 94
INTERNATIONAL EX CRYSTAL & EX KITS
OSCILLATOR
RF MIXER
RF AMPLIFIER
POWER AMPLIFIER
1. MXX-1 TRANSISTOR RF MIXER
A single tuned circuit intended for signal
conversion in the 3 to 170 MHz range.
Harmonics of the OX oscillalor are used for
injection in the 60 to 170 MHz range.
Lo Kit 3 to 20 MHz. Hi Kit 20 to 170 MHz
(Specify when ordering) ......................
$3.50
2. SAX-1 TRANSlSTOR RF AMP
A small signal amplifier to drive MXX-1
mixer. Single tuned input and link output.
Lo Kit 3 to 20 MHz. Hi Kit 20 to 170 MHz
(Specify when ordering) ........................ 5350
3. PAX-1 TRANSISTOR RF
POWER A M P
A single tuned output amplifler designed to
follow the OX oscillator. Outputs up to
200 mw, depending on the frequency and
voltage. Amplifier can be amplitude
modulated. Frequency 3.000
to 30.000 KHz ........................................... $3.75
4. BAX-1 BROADBAND AMP
General purpose unit which may be used
as a tuned or untuned amplifier in RF and
audio applications 20 Hz to 150 MHz.
Provides 6 to 30 db gain. Ideal for SWL.
Experimenter or Amateur .......................$3.75
5. OX OSCILLATOR
Crystal controlled transistor type. Lo Kit
3,000 to 19.999 KHz. Hi Kit 20.000 to 60.000
KHz. (Specify when ordering) ................ $2.95
6. TYPE EX CRYSTAL
Available from 3.000 to 60,000 KHz.
Supplied only in HC 6/U holder. Calibratlon
is 2 .02% when operated in international
OX circuit or its equivalent.
(Specify frequency) ................................ $3.95
hr the
commerelal rser
INTERNATIONAL
PRECISION RADIO CRYSTALS
lnternatlonal Crystals ere available from 70 KHz
to 160 MHz in a wide variety of holders.
Crystals for use in military equipment can be
supplied to meet speciflcatlons MIL-C-3098E.
CFy'p"zgL
(GP) for "General Purpose" applications
(CS) for
Standard"
(HA) for
Hiah Accuracv" close temoerature
"Commercial
-
WRITE FOR CATALOG.
&m!h
INTERNATIONAL
More Details? CHECK-OFF Page 94
.
CRYBTAL MFQ. CO, INC.
( 0 NO L E I
OKLA
<
STY
O I L A 73102
february 1972
73
AT L A S r H I ~ ~
)4
SPifCH TOMMf<50Rnwr
REALLY WORKS!
<
RPC-3M MODULE
(ONLY $22.50)
I.OW D I S T O R T I O N
CIncurr
RPC.3C CABINET MODEL
FULLY WIRED B
($34.95)
TI!S'I~F.I) N 0 1- A K I T
WORKS W I T H
PIiONE PATCH
INTERNAL UNITS
I
M O I I U L E S WORK
MOHI1.E
FULL WARRANTY
-ONE Y E A R
INlRODUCTORY
L O W PRICES
RPC-3.3U INTERNAL UNIT
( I l l i n o i s rcsidcnts a d d
($24.95)
5 ' ; Sales T a x )
W r i t e f o r specifications
a n d i n f o r m a t i o n sheets
E I ~ C ~ ~ O
(free)
BOX 1201H
D e m o n s t r a t i o n T a p e (cassette) available ( $ 2 . 0 0 dc- C H A M P A I G N , ILL.
posit )
61820
5
Many thousands of you have
become very familiar with the
various
Radio Society o f
Great Britain books and handbooks, but very few of you
~ ~ C S
are familiar with their excellent magazine,
Radio Com-
munication.
It includes numerous technical and construction articles
Depend on
in addition
. ..
We can supply crystals
from 1 6 KHz t o 80 MHz i n
many types of holders.
Over 6 million crystals i n
stock including CR1AIAR,
FT243, FT241, M67, HC6/U, HC13/U, etc. ORDER
DIRECT w i t h
check o r
to JAN
CRYSTALS. For f i r s t class
mail add 15C per crystal
- f o r airmail, add 20C per
crystal. Inquire about
special quantity prices.
t o a complete
rundown on t h e month's
events i n amateur radio.
Surely a most interesting addition to your amateur radio
O'~'~h\N~\~R
activities.
2400 Crystal Dr.
We can now offer this fine
F~o~d~.;;;l
(813) 936-2397
the other advantages of mem-
ELECTRONICS. INC.
magazine t o you along with
bership in the RSGB (such as
s e ~ ~ t ~ ~ ~ g f ~ i ~ w
oscillator circuits
and lists of
thousands of
use of their outgoing QSL
Bureau) for $10.25 a year.
order today from
SPECIALS
Color TV crystal 13579, 545 KHz) wira leads
4 for
100 KHz frequancy standard crystal (HC 131UI
1000 KHz frequency standard (HC 6/U)
Any CB crystal, trans. or rec.
(except synthesizer crystals)
Any amateur band crystal in FT-243 holders
(except 80 - 160 meters)
$1.60
5.00
4.50
4.50
2.50
corn,*=
BOOKS
Greenville, New Hampshire 03048
1.50
80 meter crystals i n FT-243 holders
74
f e b r u a r y 1972
More Details?CHECK-OFF Page 94
BC-645 TRANSCEIVER
EASILY CONVERTED FOR
14 PAGES,
b g o a n hp
420
Mc. O P E R A T I O N
Ivrplu tl.cnoncc G o . wall pay rou to
~ J E ~2D
sC
6r'l
in Amwicol
It
t.fudd with y a r
-
la you copy
TG-34A
-0th
cranmd
-
lint order.'
CODE KEYER, "11-taind,
r w o d v c a code pactice s i p l s f m
ovtormtic,
top.
5 to 11 WPM h i l t - i n r p o k r . band m with A
1
.
monuol. tokeup reel ord AC lin C P ~ .
Cod. p a r i c e topn la obr. P.U.R.
HEADSET Lor. impdance. With lorwe chomoi~w r curhionr.
I - f i cord orrd plug. l e g . 112.50. O w 5~0ci.l Rice$2,95
Le~sear cushions..
11.95
1 .69
High impdonce odapor for a h . .
...$2450
................
.
sn W'
SCR-274-N, ARCS WMWD
vman..
m.
m ~ c C I v r n .
190- 50Kc
6 9.1 Mc
1.5-3Mc
-
-
TIANSWITT~IS.
enolrn
....
....
....
4 5.3 Mc
5.3 - 7 Mc
-
....
....
.I..
.
M
E.<.
l,.d
T r u
8C-453
8C-455
R-25
r m n..
116.95
101
NEW
,,,,
us€
... - ... 27
....... r -m ...
...
.......
.......
C-kt.
nta
BC-457
8C-458..
.....
.......
58.95
18.95
123. 50...
50
122:s
119. SO... 121.50
...
...
--
...I11.95
-.
,
,,
,
m
i ,
i n origlml factory c&
$16 95 cOv$c
DEPENDAIL1
TWO WAY
FRMUENCY RANGE: About 435 to 500 Me.
TRANSMITTER h o I 4 t u b : WE-316A, 2dF6, 7F7
RECENER hm 11 tubes: 2-955, 4-7H7, 2-7E6, 3-7F7
RECEIVER I.F.: 40 Mc.
SIZE: 101/2" x 131/2" x 4 k m . Apg Wt 25 Ilr.
...111.95
'fIm
(a h l l l k T d l n g l
AN/APR
4Y F M L. A M R K E m
High p u i s i a lab i r r m t , (or menitwing ond
m v i n g h-y
a d relatiw s l p l I&,
30 to 4QX k . in 5 runin9
For 110 v 60 cycl. AC. hilt-In pp.r 1 ~ 1 Origin01
~ .
clrcvit
dilnclvdd. C k k d ou)
..Iut.
LIKE NEW
All tming unih m.oilobl. f a o h . P.U.P.
BRAND NEW, camplste
with I 5 t h , 1- dm-
*rb
quality canpwntr md circulhy, I d w l fa tha teehniclon
e n p ~ i m e n t u .hby fobulaa uprimenla, for uanple: you can
comhuct o Yogi antema for the 420 Mc b o d thot w i l l produce
a w i n of 10 db and yet fit on yow -ding
desk1
..........:.......
ACCESSORIES FOR BC-645
...........$l.SO
MOUNTING for M a 5 Trmrceiva.
PE-101~DYNAMOTOR, 12-24 volts,
(easily c o ~ ~ a t to
e d6 w l h )
MOUNTING for PE-1OlC Dynanota
UHF ANTENNA ASSEMBLIES(nt of 2). per w t
COMPLETE SET OF 11 CONNECTORS
CONTROL BOX BC-646
MOUNTING for BC-646 Control Con
BC-1206-C RECEIVER
Aircmft thocon R r
caiver 200 b 400 Kc. Op.mtn hom 24V DC 1.5A.
C o n t i m u . tuning, ml control, on-of1 switch a d
phone jock. V c v umitivs. C-t.
complete with tubs, NEW
92.50
................. 7.95
........... 1.00
... 2.95
.......... 5.95
.............
...................... 2.95
........... 1.00
BC-604 F M TRANSMITTER 20 b 27.9 ~ c .
O v l p l opprox 30 won%. 10 c r y b l controlled
channels. Complete with tubas.
NEW
...........................$1250
Mob."
.............
........
MI,
..........
ARC-RlIA
ARC422
R-l/ARR-2
Q-5 I r * i v r 190 5% Khz
YO 1600 Khz I r e l r r with tuning gt+
R u e l v r 234-258
11 tubm, NEW
110.95
115.95
SB.95
..
K d O 5 INTERPHONE AMPLIFIER, N€W S3.45EXC.USED..
11.95
12-95
TELEPHONE HANDSET, W.E. lypm..
.LIKE NEW
XR-522 WANSMITTER-RKEIVER, with 18 hkr. LIKE NEWJ37.50
.........
N - I O A UHF TRANSVERTER
M d c by Aircrolt R d i o Corp. Couples UHF Antcnno to VHF nonunine and VHF rcceirn. UIM
6 lubes: 4/5763 ond 2/6201. Includes 0 cryrtols
ronging from 233.8 Mc to 257.8 Mc. Sire: 111
4-1/2x4-5/8".
Wt 5-1/2 Ibs.
LIKE NEW,with
vdols,, , ,
-. +.
BC-733 RECEIVER
Rmemiva mdio sigmls
bming korrmittmd by US m h l l i t e on
108
Mc. AM, crptol-controlld on 6 p~
in
108.3 to 110.3 Mc mng.. Opmk on 12/24 V
DC h 210 VDC @
Mo. Canpleh
I
with 10 t u b .
Con bm CWUWto FM Rmceivu
m h 1 0 g ~ hc.lkd
~ .
$5.05
EC-73% Conhol Cbn for o h , NEW..
1.75
.............
.
HANDMIKE
Rugged, h s o y d u t y corbon hondmike with pento-tolk switch. Equipped with 4-it cord 6 phom
SPECIAL
PI*.
NEW, bard..
Eoch 9.88
2 for 13.25
.....
2" DC VOLTMETER
Mown i n 2-l/B" hole. Flong. d i a t r 2-5/8"
Two u o l n : 0-15 o d W. Coliboted lor uu
on steel -1.
Stondard bond.
SPECIAL
NEW, b o x d . .
Each 11.75
2 for 13.00
.....
TELEMONE TIN RELAY
Mmd.
J.H.c~II,
h~odlulo~m
d t l v l t y . 1 Y ) h m s d l . NEW...
$3.45
...
SPECIAL PACkAGE OFFER:
Trorsceiver, Dymmo,a
occ-ie
COMPLETE,
BRAND NEW, While YocL, Lo,t
BC45
....
B C - 2 2 3 ~TRANSMITTER
~
25 won, CW, MC-,
cnlrtol conhol
on 4 p-lutd ckN.l,,
Ion* X)o b 5200 Kc by uu of 3 plugin unih,
included. Complete.
BRAND NEW
$27.50
.....................
A m - 1 F M TRANSCEIVER 400-450 ~ c F.W ~ .
M d u l a b d by moving coil honducn. Eosily con* e r f d (01 radio conmol a 70 cml. Complete with
I4 t u b , dyn.
BRAND MW
$9.95
.......................
For cod.M ~ M
TG-SB TELEGRAM SEl
I c a t k n or cod. poctlce. Rrkbla, wlth hi+
IM. T*o o more unih opmh up )o 25 m i l r op t . bll d l rylhm, 1OOO cycl* horlr, kw,
h . o d p i u , c o w a cam,bmlr.
5l.e 5 - 1 ~ 5 - 1 / ~ 1 0 ' . N W . .
.$8.95
-
........
DUAL AMPLIFIER
h a two input clrcuih w c h
f e d i n g o single 6SMGT b i n triode amplifir.
Complete wifh 115'4 60 cy. pa*- srpply
wing 6X5GT n c t i f i r . NEW..
........
WILLARD 2-VOLT STORAGE BATTERY
l o t 4 ot X ) AMP.-~ovl.W
20-2.
.I ~.chmp.oble.
TFHMI:
25'1 ikp..it
Mln#$,aumo d r r
V5."O
rllh ~m4t.r. bdmnc, C.v.18. - 0 8 R r m l t ~ i~n vlull.
b . 0 . 11. N Y C . *bjvrl *I yrlvr rdr .nd yrlcr rhmngc.
G&G RADIO ElECTRONlCS COMPANY
J
4 5 - 4 7 Womn St 12ndFII Now Yo*. N Y -7
Ph 211-967-4605
february 1972
75
New
3 Digit Counter
means PROFESSIONAL
-
,
r.....
r".
.
-I
-
1
1'
7,,
Tha model fm-36 3 - d i ~ l t frequency
meter has the same features that has made
the 2 diglt model so popular w ~ t h Hams
low price, small size (smaller than a
QSL card). 35 Mhz top frequency. simple
connectlon t o
our transmitter. +0 ,-0.1
Khz readout
the added convenience
of a third digit to provide a 6 digit capa.
bility. Kit or Assembled.
Example: 28.649.800 Hz reads 28.6 MHz
or 49.8 Khz.
(Add the 10 Hz module t o
read 9.80.)
FU-36 KIT $134.50
-
You Can Rely On
- LLUS
NEW..
SPECIALISTS
'Controlled Quality Crystals
LCRSTEK
....
300 MHz PRESCALER only 545.00
with f m - 3 6 order
Micro-Z
Co.
Box 2426 Rolling Hills, Calif. 90274
ALL SOLID-STA TE
SSB TRANSCEIVER
formerly Texas Crystals
Div. Whitehall Electronics Corp.
1000 Crystal Drive
Fort Myers, Florida 33901
41 17 W. Jefferson Blvd.
Los Angeles, California 90016
SURPLUS CRYSTAL FILTERS
.
.
..
.
.
.
Complete slngle-band SSB transceiver 4 to 5
watts PEP output 15. 20. 40 or 75 meters.
VFO tuning 3750 t o 4000 on 75. full coverage
on 40. 20 and 15 meter amateur bands.
Suitable for dry battery operation.
Light weight, small size, makes excellent
portable - boat, aircraft, field or mobile.
Contains 15 transistors, 1 mosfet, 2 Darlington amps. 1 I.C. and 17 diodes. Four-pole
filter.
Available accessories. AC power supply, MIC.
headsets. lightweight dipole and 40 watt PEP
linear amplifier.
Xtal controlled eme enc and net transceiver
available. Write f o r T u l l rnformation on transceivers and accessories.
~ A T A L O -FILTERS
G
AND CORES -NEW B SURPLUS
CARBONYL"E"
TOROID CORES
2"DIA. T-200-2
69 DIA. 1-68-2
b2.75 OR
EACH 50 t OR
EACH
3 FOR
7 FOR
NEW
(7.00
(2.76
JUSTIN INC.
2663 LEE STREET
SOUTH EL MONTE. CALIF. 91733
76
february 1972
M o r e Details? CHECK-OFF Page 94
R. L. Drake Company makes radio communications equipment
t o satisfy the needs of the most discriminating user. There's
at least one item of Drake gear just right for you . . .
TRY IT.. .
We're sure
YOU'LL LIKE IT!
R. L. DRAKE COMPANY
540 Richard St., Miamisburg, Ohio 45342
Phone: (513) 866-2421
Telex: 288-017
More Details? CHECK-OFF Page 94
february 1972
77
AMPEREX
READOUT
Brand new
$3.00 ea.
10/$25.00
COUNTING
PACKAGE
Amperex Tube
SN 7490
SN 74141
All above $6.75
-
VIDICONS
Fantastic Prices.
Send for List.
Giant Alpha-Nurnerlc Neon Readout.
Complete alphabet plus all digits, 15
segments. 2%" high. $3.00 each. I0
f o r $25.00. Sockets available at 50t
each.
Transmitter
--
4
r%--
TCS
-
=7
-
Colllns Deslgn:
1.5 t h r u 12 mcs. 4
channel crystal o r tuneable, voice or CW.
Receiver is f ~ n efor general short wave listen~ng.
Transrn~tter IS excellent for the Ham. Nov~ce.
CD, etc. First class c o n d ~ t ~ o nw. ~ t hschemat~c
and power supply Info. $40.00 each unit o r
$75.00 the pair.
MM500 Dual 25 bit shift register
MM502 Dual 50 bit shift register
MEM 511 MOS P.channel FET
1 arnv diode 1000 PIV
8/1.00
1 amp diode 1500 PIV
4/1.00
2 amo diode 1000 PIV
6/1.00
--
--
-
$2.50
3.50
1.00
-
Please add postage for above items.
Send 2 5 ~
for Surplus Catalog
...
JOHN MESHNA JR. ELECTRONICS
P.O. Box 62 E. Lynn, Mass. 01904
CLOSED
- VACATION
from Feb. 14 to Feb. 29, 1972
inclusive
BC ELECTRONICS, c/o Ben Cohn
m a l l address: 1249 W. Rosedate Ave.
store: 5696 N. Ridge Ave., Chicago, 111. 60626
AMERICAN CRYSTAL CO.
1623 Central Ave., Kansas City KS 66102, 913-342-5493
Mfg. Crystals for most communication Equip.
Small Orders Accepted
For use in:
Crystal prlces @ .002%
TWO WAY
SCANNERS
MONITORS
TRANSMITTERS
C.B. SYNTHESIZERS
10 to 44.9Mhz
5.35
REPEATERS
45 to 55.9Mhz
6.10
$5.00
SCANNERS (ope?. 152.50 to 163.50 Mhz .002%)
ELEMENT CRYSTALS .0005%
(channel freq. changed in customr's element)
15.00
C.B. (Class D Slnole channl)
2.75
AMATEUR NOVICE, (HCb/U, " 1 kc, 32 mmF, Fund.
3.5-8.9 Mhz
3.00
Extras: Oven use $1.50, Submlnlature 256, .093 pins 10c
Postage 1-2 crystrls 2 or. each additional 1-2 crystals 1or.
Write for quantity discount
concise!
RADIO CONSTRUCTOR is almost exclusively construction
material. Clearly written, concise articles give you full details
on:
Audio Construction Projects
Receiver Construction Projects
Transmitter Construction
Projects
IJ Test Equipment Projects
IJ Radio Control Projects
...and much more
Try a subscription to this interesting and informative magazine, we are sure that you will
not be disappointed.
ONE YEAR SUBSCRIPTION
- $7.00
Write
RADIO CONSTRUCTOR
Greenville, N. H. 03048
Name....................................................................................
Address.............................................................................
City
State..................
Zip.....................................
M o r e Details? C H E C K - O F F
Page 94
Everything you always wanted
in keyers and QRP equipment.
POWER-MITES
1
Argonaut
MODEL PM2B
MODEL PM2B. Popular two watt CW
transceiver. Operates on 80-40-20 meters. Side-tone. Lantern battery or 12
VDC power source. Size 10%" W X
4M" H X 6%" D. Weight 2% Ibs.
Prlce $64.95.
MODEL PM3A. Advanced 5 watt CW
transceiver. Operates on 40-20 meters. Side-tone. Push pull final. Pi
Network. Break-In keylng. Size 10%"
W X 4%" H X 646" D. Weight 3 Ibs.
Prlce $79.95.
The Argonaut is for every ham.
A transceiver that operates
on an AC pack or lantern battery.
Covers Amateur bands 80-10,SSB and CW.
ANTENNA TUNER
MODEL AC5. Matches 52 ohm output
of Power-Mites to open wire on random length antennas. Maximum power
10 watts. Size 4" W X 2" H X 4" D.
Price $8.95.
Weight 1 Ib. 4 oz.
Completely solid state. Permeability tuning. Less than 100
Hz drift. % uv sensitivity. 9 MHz crystal filter. 2.5 kHz bandwidth, 1.7 shape factor. Amateur bands 3-30 MHz. AGC.
Speaker, SWR bridge, S-meter built-in. Instant CW break-in.
Side-tone. Plug-in circuit boards. Selects normal side band.
reversible. One control tune-up. 50-75 ohm push-pull output.
Direct frequency read out.
SWR BRIDGE
Argonaut price
Power supply
Microphone
MODEL AC4. Favorite for ORP. Measures from % watt to 200 watts. Size
4" W X 2" H X 4" D. Weight 1 Ib.
4 OZ.
price $14.95.
$288.00
$24.95
$17.00
KEYERS AND KEYER PADDLES
SlGNALlZER
v
-
C
S20
MODEL S20. Complete audio and
speaker system for receiversltranceivers. Plugs into headphone Jack.
Provides maximum AGC to keep all
signals constant level. Front panel
headphone lack. Size 8%" W X 41/z1'
H X 6%" D. Weight 3% Ibs.
Price $39.95.
MODEL S30. Similar to 520 but has
built in FR4 CW litter: switchable.
Size 8%" W X 4'/2" H X 6'/2" D.
We~ght4 Ibs.
Prlce $49.95.
MODEL KR40. Squeeze keyer. Iambic
sequence. Full memories. Variable
weighting. With dual paddles. Speeds
from 6-60 wpm. 115 volt AC operation.
Side tone. Size 4%" W X 21/z1' H X
8" D. Weight 4 Ibs.
Prlce $89.95.
MODEL KR20. Keyer. Self-completing.
Onloff weighting. With dual paddles.
Speed 6-60 wpm. Monitor side tone.
115 V AC operation. Size 4%" W X
2'/z1' H X 8" D. Weight 4 Ibs.
Price $59.95.
Ask your TEN-TEC dealer to show you our complete line. If there Is no dealer i n your area, send
your order direct. Include $2.00 shipping for each
Argonaut, all other items shipped postpald.
More Details?CHECK-OFF Page 94
imr
MODEL KRS. Keyer. Self-completing.
Optimum weighting.
Single paddle.
Speed 6-60 wpm. Operates lrom
Or
12
Size 4"
2"
6" D. Weight
Ib. Oz. Price s34.95.
MODEL KR1. Paddles as used in KR40
and KR20. Mounted in formed atumicase. Size 41/4"
2"
D. Weight Ib.
Price $18.95.
MODEL KR2. Paddle as used in KR5.
Mounted in formed aluminum case.
S u e 4%" W X 2'' H X 6" D. We~ght
ll/z Ibs.
Price $12.95.
~ e p t J-2
.
TE N-TEC.INC.
H~ghway
41 1East
C ! Scvierville. Tennessee 37862
february 1972
79
The most powerful signals under the sun!
When You Really Know..
w-
a
GT-550A Transceiver
Unmatched dependability, flexibility and low cost
Top performance either fixed station or mobile
Higher power output than other popular transceivers available today
Standard of the industry in frequency stability
Outstanding receiver stability and selectivity
Full line of accessories for integrated station capability
Ham Net $495.00
Order No. 855
I
I
I
RV-550A Remote VFO
Solid-state construction
Complete with plug-in cables
Function switch controls Receive-Transceive-Transmit frequency independently
Ham Net $95.00
Order No. 856
RF-550A R.F. Console
Contains precision wattmeter with top accuracy in range of 3.5/30.0
MHz
Switch select forward or reflected power-calibrated scales are 400 and
4,000 watts full scale
Switch select 5 antennas plus a dummy load
Ham Net $75.00
Order No. 857
RB-550A Rotator Control
All new control head for Hy-Gain model 400 Rotor Brake Rotator
Contains solid-state logic circuit to furnish electrical information for
rotation and control of tower mounted rotator
Ham Net $59.95
Order No. 859
I
80
SC-550A Speaker Console
Matching speaker with headphone jack for the transceiver, complete
with cable
AC-400 power supply mounts inside console
Ham Net $29.95
Order No. 858
february 1972
More Details? CHECK-OFF Page 94
..Quality Equipment........
! GT-550A System
Phone Patch PR-550
Order No. 812
Ham Net $49.00
Crystal Controlled Adaptor XO-550
Order No. 81 1
Ham Net $49.00
AC Supply AC-400
Order No. 801
Ham Net $99.95
Mobile Supply G-1000DC
Order No. 802
Ham Net $129.95
CW Filter F-3
Order No. 808
Ham Net $37.50
Calibrator CAL-250
Order No. 806
Ham Net $25.00
VOX Accessory VOX-35C
Order No. 807
Ham Net $29.95
Mobile Dashboard Mounting Bracket-GTM
Order No. 809
Floorboard Adaptor-ZZM
Order No. 810
Ham Net $8.95
(Not Shown)
Ham Net $6.00
Make Your Choice Quality. ..All The Way!
HY-GAIN ELECTRONICS CORPORATION
P.O. Box 5407- WB Lincoln, Nebraska 68505
More Details? CHECK-OFF Page 94
february 1972
81
H1
~ E V I C E S
HAL DEVICES
MODEL 1550
ELECTRONIC KEYER
ANNOUNCING
All llir fst,~tilrt.sof Drevlous HAL kevers and more
TTL clrcuftrv 0pllonal ident~fierfbr sending call
letters. DX and RTTY ops, take notice. Tranristor switch~ngfor grid block AND cathode keylng.
Rugged crackle cabinet with brushed aluminum
panel. Designed for ease of operation.
Model
1 5 5 0 only $ 6 4 . 9 5 . W i t h I D $89.95.
Complete parts k ~ for
t
ItIra W G F F C ST 6 now includes all parts exct pt cab~net Only 7 HAL circuit boards (drilled G I 0 glass) for all features.
Plug.in IC sockets. Custom transformer by
Thordarson for b o t h supplies. 1 151230V.
50-60Hz. $135.00 kit. Screened table or rack
cabinet $26.00. Boards and manual $16.50.
Shipping extra. Wired units available.
HAL TOUCHCODER II KIT $55.00
Complete parts klt, excluding keyboard, for the
W4UX CW code-typer. All circuitry on one 3 x 6"
G I 0 glass PC board. Plug-in IC sockets. Optional
contest ID available. $35.00. Watch for announcement of the new HAL code-typers. both
Morse and RTTY.
HAL ARRL FM TRANSMITTER KIT
Drilled, plated, glass epoxy HAL PC boards.
2N5913 final transistor. RF detector with 0-1 ma.
meter added. All parts, and the RF detector and
meter only $50.00
shipping. Cabinet and
crystals excluded. Board only $7.50.
+
OTHER HAL PRODUCTS
ID-1 REPEATER IDENTIFIER . . . $75.00 wired
W3EFG SSTV CONVERTER.. . . . . . . . 5 5 . 0 0 kit
DOUBLE BALANCED MODULATOR.. . . 6 . 5 0 kit
DIP IC BREADBOARD CARD.. . . . . . . . . . .5.50
MAINLINE ST-5 TU KIT. . . . . . . . . . . . . $50.00
MAINLINE AK-1 AFSK KIT.. . . . . . . . . . . . 27.50
HAL RT-1 TU/AFSK KIT.. . . . . . . . . . . . . 51.50
rnIIUII*,
&
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ma,.
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-11
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ORDERIN6 INFORMATION
Catalog. includ~ngphotos, of all items 24C postage. Please add 75C on parts orders. $2.00 on
larger kits. Sh~ppingvia UPS when possible. Give
a street address.
HAL DEVICES, B o x 365H, Urbana, 11 61801
Phone 21 7-359-7373
82
february 1972
The HAL DEVICES RVO-1002
A revolutionary approach t o amateur radio teletype. The RVD-1002 provides:
Display of 60, 66. 75, and 1 0 0 W P M 5 level
TTY
1 0 0 0 character display in 2 0 lines of 5 0 characters per line
Selectable letters shift o n space
Manual control of line feed and letters shift.
Standard CClR video output for use with modfied TV receiver
' Noiseless operation with solid state reliability
RVD-1002 (assembled). . . . . . . . . . . . . . .$ 4 9 5
RVD-1002 R (rack mount). . . . . . . . . . . .$ 4 9 5
ST-6 (assembled). . . . . . . . . . . . . . . . . . . . $ 2 8 0
ST-6/AK-1 (assembled). . . . . . . . . . . . . . . $ 3 2 0
TTY KEYBOARD. . . . . . . . . . . . . .available soon
Modified solid state TV receivers will be available. Write for details.
HAL DEVICES, B o x 3651-1, Urbana, 11 61801
Phone 2 1 7-359-7373
M o r e Details? CHECK-OFF Page 94
-
flea w t
market
-
TOROIDSI LOWEST PRICE ANYWHERE. 40/$10.00
P O S T P A I ~(5/$2.00). Center tapped 44 o r 88mh
32KSR pa e grinter reconditioned: perfect $221:
MITE UGC 1K R
printer, reconditioned. $250.
Model 28 sprocket to friction kit, $25. Model
l5KSR $65. Matching RAE7 P.S. unused. $5. Sync
motor;.
$7. 14TD 60 speed, $25. 14DPE tape punch.
$15. HP 2OOCD audio oscillator. $75. 11/16"
reperforator tape 40/$1:00.
Model 33ASR complete $650: ~ t a m ' pfor Ilstlng. Van WZDLT, 302H
Passaic, St~rllng,N. J. 07980.
g
-
--
I RATES C o m m e r c i a l A d s 25g per
word; non-commercial a d s 10q! per word
p a y a b l e in a d v a n c e . No c a s h discounts
or a g e n c y commissions allowed.
I COPY No special l a y o u t or a r r a n g e ments available. M a t e r i a l should be typewritten or c l e a r l y printed a n d must include full n a m e a n d a d d r e s s . W e reserve
the right to reject unsuitable copy. Ham
Radio c a n not check out e a c h a d v e r t i s e r
a n d thus c a n n o t be h e l d r e s p o n s i b l e for
c l a i m s m a d e . L i a b i l i t y for correctness of
m a t e r i a l limited to corrected a d in n e x t
a v a i l a b l e issue.
D e a d l i n e is 15th of
second preceding month.
I SEND MATERIAL TO: Flea M a r k e t ,
Ham Radio, Greenville, N. H. 03048.
TOLEDO MOBILE RADIO ASSOCIATION'S 17th Annual Hamfest and Auction will be held February 20,
1972. $1.00 registration. open table sales, map and
info write: TMRA, W8HHF. Box 273. Toledo. Ohio
43601.
MOONBOUNCE: World record 1296 MHz equipment.
16 foot polar mount and 10 foot El.AZ dish. Power
amplifiers (2) 600W and 350W output. Parametric
amplifier and converter. Power supplies and all
exitation equipment. Feedline, feeds and all peripheral equipment t o operate SSB. CW. AM and FM.
Equipment described in Aug. 68 and Aug. 69 Ham
Radio. Also test equipment and components for
general microwave work. Contact Peter Laakmann,
WB610M. 8001 Airlane Avenue. L.A. 45, Calif. 90045.
Phone 213-391-0711 Ext. 4629 during worklng hours.
-
SURPLUS MILITARY RADIOS Electronics, Radar
Parts, tons of material f o r the) ham, free catalogue
available. Sabre Industries, 1370 Sargent Avenue,
Winnnipeg 21, Manitoba, Canada.
TOROIDS 44 and 88 mhy. Un otted 5 for $1.50
ppd. W. Weinschenker, Box 35$, l r w h , Pa. 15642.
-
TELETYPE MACHINES
Kleinschmidt Mod 125
(FGC-20) $125 each, complete tape set (FGC-25)
2175 each. reaerf (TT-109) $40 each. Teletype Corp.
hid 14 t y p i n g reperf W/KB-D $50 each, reperf only
rebuilt $30 each Mod 14 TD $15 each. Stelma
TT-63A repeater $30 each. FOB Long Beach. John
Fageol, WA6TA0/6. 3563 Conqulsta, Long Beach.
Cal. 90808 - 213-429-5821.
-
KIT BUILDERS
All American Sp,orts Amplifier
(featured Sept. 1971 Popular Mechanics) now available with step by step instructions. Fantastic new
(patent pending) amplified filter concept doubles
Free data sheet.
normal TV v ~ e w i n g range.
CADCO SYSTEMS. Box 18904, Oklahoma City,
Oklahoma 73118.
-
YAESU FTDX400 TRANSCEIVER: 500 watts SSB,
440 watts CW, 125 watts AM. Like New. $350.00:
Robert Cook. W6PJA, 4303 Snowden, Lakewood.
California 90713 . . . 213-429-4442.
-
ATTENTION DEALERS
stock All American
range TV receiving kits.
Sports Amplifier Ion
featured September 1871 Popular Electronics. Write
Dealer Division. CADCO SYSTEMS, Box 18904,
Oklahoma City, Oklahoma 73118.
HALLAMORE TELEVISION SYSTEM: R e c e i v e r
MR17A, Camera CC400A. used on VHF amateur
television . . $125.00. ,Robert Cook, W6PJA. 4303
Snowden, Lakewood, Callforn~a90713. 213.429-4442.
.
-
"DON AND BOB" GUARANTEED GOODIES. Monarch
KW SWR-FS meter 8.88 plus 1.50 postage/handling;
Ham-M 99.00: TR44 59.95: Mosley CL33 114.00; Hy~ a i nT H ~ D X X 139.00. w r i t e quote list. Capacitors:
O V Vacuum 50PFl
Sangamo D C M ~ O O M + D / ~ ~4.95:
7.5KV 1.95: Superior Powerstat 1368 59.95; Ray
6LQ6 3.50: #14 Antenna Wire 1.95/C:
MOT
MCl709CG Opam (709) 506' MOT HEPI70 E oxy
Diode 2 . 5 ~ / 1 0 0 0 ~396;
h
~ a l l i k ' a f t e r sSX115 258.00:
Copper Ribbon
Clairex 604 Photocell $00'
10d/Ft; KY65 Code ldentlfle; 5.95; 4Co"d/5Ft Coil.
cord 50d: Temoo Kenwood Dealer. Prlces collect.
Kastercharge, BAC. Warranty guaranteed. Madison
Electronics, 1508 McKlnney, Houston, Texas 77002
(713) 224-2668.
EXCLUSIVELY HAM TELETYPE - 19th year, RlTY
Journal, articles, news. DX, VHF, classified ads.
Sample 30d. $3.00 per year. Box 837. Royal Oak,
Michigan
- 48068.
-
COLLINS Mechanical Filters. 455 kHz., 2.4 kHz
bandwidth. $11.00 Postpaid. V. Mozarowskl, VE3AIA.
1 Belgrove Drlve, Islington, Ontarlo, Canada.
-
-
QSL'S
BROWNIE W3CJI
31118 Lehigh, Allentown. Pa. 18103. Samples 106. Cut catalogue 254.
2MFM. 50W, MOTOROLA 53GJV. two with accessories, tuned on 146 MHz. one with no xtals $ 100.
Other with .34-.94, .85..85, .94-.94, 32-.70. $150
W6DZ0, 1021 W. Cedar Avenue, Redlands. CA.
92373.
-
TV & RADIO TUBES 366. FREE catalog. Cornell.
4219 N. Univers~ty, San Dlego, California 92105.
NEW ELECTRONIC PARTS. Buy-Sell. Free Flyer.
Large catalog $1.00 deposit. Bigelow Electronics,
Dept. HR. Bluffton, Ohio 45817.
-
HEATH SB-100 with AC supply, absolutely mint
condition $300.
Hallicrafters HT.32 transmitter
FB $180. Both shipped prepaid. Cline. WB6LX1/7.
Box 6127. Salt Lake C ~ t y ,Utah 84106.
-
2ND WORLD SSTV CONTEST: 1st Period 15.00-22.00
GMT, February 5. 1972: 2nd Period 07.00.14.00 GMT.
February 13. ,1972. All autohirzed frequencies. Exchange conslsts of pictures and number of the
message. A two way contact with a station receives
one point (total points will be the numper of individual stations contacted). No extra polnts for the
same station contacted on different bands. A multiplier of 10 points for each Continent and of 5
points for each Country (ARRL list) worked is
given. Total exchange polnts tlrnes,the total of the
multipliers. Log will contain: date, tlme. GMT, band.
call sign, message number sent and received.
points. All logs must be received by March 20.
1972. Send them to: Prof. Franco Fanti, via A.
Dallolio 19. 40139 Bolonna.
Italy.
-
-
BUYING? SELLING? TRADING? Don't make a move
until you've seen our new publication! Free sample
copy! Six issues $1. Ham Ads, P. 0. Box 46-653G,
L.A.. Cal. 90046.
TELL YOUR FRIENDS about H a m Radio Magazine.
february 1972
83
Semiconductor Supermart
MOTOROLA
RCA
FAIRCHILD
NATIONAL
HEP
PLESSEY
-
DIGITAL READOUT
a price
everyone
can a f f o r d
SPECIAL OFFER
..
At
..
.
$3.70
Digital readout
BCD t o 7
Segment
-
Decoder/driver
7490 Decade Counter
Operates from 5 VDC
Same as TTL and DTL
Only
$8.50
Will last 250.000 hours.
3.5 W AUDIO AMP IC
HI-FI QUALITY
$3.95
with 12 pages of
construction data
MC1550
CA3020
CA3020A
CA3028A
CA3001
POPULAR IC'a
Motorola RF amp .............. ..$1.80
RCA 'h W
RCA 1 aud
RCA RF a m
RCA
56-66
MC1350P
MC1357P
MC1496
MFC9020
MFC40lO
MFC8040
MC1303P
MC1304P
High gain RF amp/lF a m p ...... $1.15
FM IF amp Quadrature det
$2.25
Hard t o find Bal. Mod. . . . . . . . . . $3.25
Motorola 2-Watt audio . .
$2.50
Mult1.purpose wide-band amp $1.25
Low noise preamp . . . . . . . . . . . . . . . . .$. 1.50
Dual Stereo preamp ..................$2.75
FM multiplexer stereo demod $4.95
MPF102
JFET
MPF105/2N5459
MPF107/2N5486 JFET
MPF121
Low-cost dual
MFE3007
Dual-get
VHF RF
7475 quad
7495 shift
7493 divide
MC724
MC788P
MC789P
MC790P
MC799P
MC1013P
MC1027P
MC1023
. . . .85
SlGNETlCS PHASE LOCK LOOP
NE561B $9.50
NATIONAL LM309K 5V, 1A regulator.
using TTL you need this one.
NATIONAL DEVICES
LM37O AGC/Squelch amp
LM373 AM/FM/SSB strip
february 1972
7441NlXlE
60
PLESSEY INTEGRATED CIRCUITS
GREAT FOR SSB RCVRS AND XMTRS
SL610 low noise
150 M H ~
RF good AGC $5.65
SL612 lowdistortion IF good AGC . . . . . $5.65
SL621 AGC generator for ssB rcvrs ............
~
8
SL620 AGC gen. SL630 Audio .
.
$8.30
SL630 multipurpose audio amp . . . . . . $5.35
SLMO top performing balanced mixer $10.88
S L M 1 low.noise rcvr mixer .........................$ 10.88
84
DIGITAL BARGAINS
FACTORY FRESH TTL IC's
MSD047 decoder/d
digital readout
.
MOTOROLA DIGITAL
Quad 2-input RTL Gat
Dual Buffer RTL
Hex Inverter RT
Dual J-K Flip-flop ...............................
$2.00
Dual Buffer RTL....................................
$1.00
85 MHz Flip-flop MECL
....... .$3.25
120 MHz Flip-flop MECL .............$4.50
MECL Clock driver ..................... $2.50
TRANSISTORS & DIODES
MPS6571 ............................................................60
2N5188 ................................................................................... 79
2N706
~
~ packet of 4 ....................................$1.00
1.00
2N2218 packet Of
1.00
lN4OO1 packet Of
1.00
lN4002 packet of
IN4004 packet of 6
1.00
Please add 35Q for shlpplng
I f you are
.85
.85
CIRCUIT SPECIALISTS CO.
Box 3047. Scottsdale, AZ 85257
FACTORY AUTHORIZED
HEP-CIRCUIT.STIK
DISTRIBUTOR
M o r e Details? C H E C K - O F F
Page 94
FOR SALE: National NCX-3 200W xceiver. NCX.A
110 Power Supply, G.E. Mike Model EM286 same
as 444. CB xceiver Lafayette Micro.12. Best offer
o n any or all. Gerry Surprenant, Betty-Jean Drive,
Monson. Mass. 01057.
HELP!
from Bill Orr, WGSAI
Cushcraft
ASK HARRY FIRST Ameco. Cleg
Galaxy, Hallicrafters. HyGain, M O S ~ ~ ~~ e. g e n c ~ :
Sonar, Simpson, Ten Tec, others.
ood trades
accepted. S.A.S.E. Name literature wanted. Harry's
Amateur Radio Supply, 3528 Gaskin Rd. (Belgium)
Baldwinsville, N. Y. 13027. 10AM.9PM. Closed
Sunday. 315-635-7452.
5 GREAT BOOKS from
QSLS.
SECOND
Samples 25d. Ray,
Utah 84015.
ALL ABOUT CUBICAL QUAD ANTENNAS
TO NONE. Same
K7HLR,
-
day service.
Box 331, Clearfield,
Amateur Radio's best known writer
2 METER FM GEAR for sale: Motorola L43 base on
146.58 $160. T43 trunk m t g 2 freq on 146.58 and
146.76 $150. GE MA36W trunk m t g 4 freq on 2M
$250. FDFM-2 l o w on 2 transistorized 6 channel
$185.
transceiver l2VDC w/AC power su ply
W7YHS, 319 N 26th Street, Billings, ~ ~ ' 5 9 i 0 1 .
Willlam I. Orr, W6SAI
Long considered "THE BOOK" on Quads this
latest edition has more information on these
popular antennas than you will find anywhere
else. Everything you need to desi n, build
and adjust your Quad for top performance.
Only $3.95 p o s t p a i d
40' TOWER WITH GUYS. Pick-up only. $50.00. Ham-
BEAM ANTENNA HANDBOOK
M rotor $50.00. Box 87. Topsfield. MA 01983.
-
-
VHF NOISE BLANKER
See Westcom
Dec. '70 and Mar .'71 Ham Radio.
ad
in
TONE ENCODERS AND DECODERS - New line of
solid state encoders and decoders compatible
with any sub.audible continuous tone system. Small
i n size, usable from 67-250 Hz. $8.95 t o $14.95.
Send for literature. Communications Specialists.
Box 153. Brea. Calif. 92621.
-
WANTED for unique collection. Original rigs per
QST, CQ, HAM RADIO articles. Close copies also
desired. Rigs will remain unmodified and will be
kept on the air. KlETU. Charles J. King. 100 Laura
Lane, Rocky Hill, Ct. 06067.
-
SAVE MONEY on parts and transmittin receiving
tubes. Forei n-Domestic. Send 256 7br giant
~ e f u n d e d first order.
United Radio
catalog.
Company, 56-HR Ferry Street, Newark, N.J. 07105.
-
AMATEUR SALES AND SERVICE before you buy i t
anywhere give us a chance t o quote you a price.
Alpha 70, Clegg. Regency. Robyn and Mosley are
lust a few of the leading names we sell. Write or
call today. Amateur Sales and Sewice, 1115 Norris
St.. Raleigh. N. C. 27604. Tel. 1-919-833-2412.
-
International Amateur Radio
NU SIGMA ALPHA
Fraternitv. M e r n b e r s h i ~ now available. Includes
wall ceaificate. I.D. card, newsletter, and more.
Send for free brochure. Box 310. Dept. H, Boston,
MA. 02101.
COLLINS SALE: 30S.1 Ampl. $980.00: 75s-3C Rcvr.
$560.00. 32s-3 Xmtr $495.00' 516F-2 Pwr Supply
$95.00. 'call: J. Kelley 1150 i 7 t h St. N.W., Washington. D. C. 20036. T ~ I .202/466-4793.
FOR SALE: Best reasonable offer. 1 Clegg 22'er
- Never used. 1 NCX-3, NCX-A. factory realigned.
1 Hammarlund 1 7 0 C realigned. L. L. Baumgartner,
Croton Falls, N. Y. 10519.
THE LAKE COUNTY AMATEUR RADIO CLUB. INC.
announces its Annual Banquet to be held at
5:30 p.m., February 12. at the Scherwood Club,
600 E. Joliet St.. S c h e r e ~ i l l e , Indiana. Join us
with wife or girl f r ~ e n d and enjoy good food (all
you can eat), entertainment, speeches, awards.
and fellowship. The Scherwood Club is less than
a mile from the junction of U.S. .Routes 30 and 41.
And to help people unfamiliar w ~ t hthe area to get
to the club, we have printed a map on the back of
each ticket. Tickets are $5.00, each from Herbert
S. Brier, W9EGQ. 385 Johnson St.. Gary, Indiana
46402, and from other club members. No tickets
will be sold a t the door.
-
TMC ATS-MCU.2 Monitor Control
WANTED
(C-2995/URA-27 Control-Indicator) and ATS.50CU.2
(CU-773/URA.27) Directional Coupler. Also AN/FRR26 Manual (Navships 92557). P. F. Wilson. W7UNR,
14572 Newport Way, Bellevue. Washington 98006.
More Details? CHECK-OFF Page 94
Willlam I. Orr. W6SAl
For many years this book has been the bestseller on beam antennas. It covers all areas of
the subject, both theory and practice. Recornmended by such famous DXers as W4BPD,
W910P. W4KFC and 5Z4ERR.
Only $4.95 p o s t p a i d
VHF HANDBOOK
b Wllliam I. Orr, W6SAl & Herbert Johnson,
X~QKI
The first complete Handbook devoted to the
Very High Frequency spectrum every published.
Selected for training and study courses by
leading universities, research organizations,
and the U.S. Armed Forces. Covers generation.
propagation and reception of VHF signals;
modes o f VHF propagation including "beyondionosphere" and moon-echo transmissions: VHF
circuitry; receiver design and construction. Also:
VHF transmitter design and construction with
powers of 2 watts t o 1-kw; test equipment!
noise figures; noise
enerators: Long Yagt
parasitic arrays; new %.band VHF beam for
50-144 MHz.
Just $3.95
BETTER SHORTWAVE RECEPTION
by Willlam I. Orr, W6SAI & Stuart D.
Cowan. W2LX
An introduction to the fascinating hobby of
shortwave listening. This clear concise handbook tells the beginner, or ,old timer how to
get more from this fasclnatlng hobby. How t o
buy your receiver. The best antennas. Where
to listen. What to look for.
Just $3.95
18th Edition
RADIO HANDBOOK
by William I. Orr, W6SAl
Latest updated edition of the famous cam.
munications handbook which is the electronics
industry standard for enpneers, technicians
xplalns In authoriand advanced amateurs.
tative detail how.to .design and build all types
of rad~ocommun~catlonsequ~pment. Includes
SSB design and equipment. RTTY circuits.
latest semiconductor circuits and IC's, as well
as special-purpose and computer circuitry.
896 pages: hardbound.
Only $13.50
order today f r o m
BOOKS
Greenville, N e w Hampshire
03048
february 1972
85
IMPOSSIBLE? BARGAINS IN SURPLUS ELECTRONICS AND OPTICS
SURPLUS T T L INTEGRATED
CIRCUITS, BRAND NEW I N ORIGINAL
MANUFACTURERS CARTONS
B & F has one of the worlds largest
Inventorle o f surplus Integrated
clrcults. All are new, meeting all
manufacturers
orq1naI
specof~cat~om, and In factory
packagong. The low proces should
speak for themselves. Manufactured
by Texas Instruments. Natoonal.
S~gnetlcsor Phllco, no cholce All
packages are 14116 lead sol~coneDual In-L~ne
Pak
NEW LOWER PRICES1
4M
7409
7410
7411
7420
7421
7430
7440
7400
7401
7402
7403
7404
7405
7408
7450
7451
7453
7454
7460
ITEMS AT
95d
7406 7470
7407 7472
7416 7473
7417 7474
7486
7426
7437
74121
7438
74122
FEATURE ITEM!
on
a Cnip".
Thos
is
technology
, tomorrows
today, and at a fract~on
of
list
price.
Tills
r e a d - o n l y program
memory, a 182 b ~ t
random memory, a
decimal arithmetic logic
unit, plus timing, control,
and outout decoders. The
,h,.
~
a r e ; eight
w,,,%,u,"\.I,$
,a,, ,c,~,,
!.." *,,0<.4#.,! .,,.,
~ , e , , . A t < # < L ~ c ,r>
, , ~ I,,*" f e a t u r e s
,b
muw
I,, Dimb
Hr
Ih.
d Ig1 t
f o u r opera.
(.*ublu cnuw ~r vc.8utd
unltt vndr lln, \U)S L\I ~ k r r rz r d t I0 n
three regis.
,t hn hm usl.*nml-l
urn* WQ1
lhan
ters floatlno or foxed
polnt decomal constant or cham operallons automatic
roundoff
leadong zero suppeston Internal keyboard
encodlng and debouncing decoded dlsplay outputs stngle
phase clock oprratlons* 28 pln DIP package onternal power
on clear
...........................................................
-
,f<>
7413
7442
7443
7444
7475
7476
7477
$1 75
7480 74141
7483 74151
7490
7494
7495
7496
74107
,.
,ins
Every TM 1802 IS a brand new Texas Instruments factory
packaged, fully guaranteed unlt The only devices requlred to
bulld a calculator are a battery, clock generator, keyboard.
display drlvers, and e~ghtd~gotsof dosplay, all avallable from B &
F Full schemat~cs,specofocat~onsand lnstructlons from T I are
oncluded
fl Texas lnstruement TMS 1802 Calculator Chip
HOT NEW INTEGRA TED CIRCUIT ITEMS1
7413
7485
74123
74153
7489
74170
74181
74182
2501
74166
74198
74199
2513
Dual NAND Schmidt Trigger . . . . . . . . . . . . . . . . S 1.75
Magnitude Comparator . . . . . . . . . . . . . . . . . . . . . . 3.75
Dual One Shot Wiclear . . . . . . . . . . . . . . . . . . . . . . 2.75
Dual 4 L ~ n e
to 1 Data Selectorlmultiplexer . . . . . .
3.75
64 Bot Random Access Memory . . . . . . . . . . . . . . .
9.75
4 x 4 Reglster Fole . . . . . . . . . . . . . . . . . . . . . . . . . 9.75
Arithmetic Logic Unit . . . . . . . . . . . . . . . . . . . . . .
9.75
Look Ahead Carry Generator . . . . . . . . . . . . . . . . .
3.75
256 Bit MOS Random Access Memory . . . . . . . . . . 9.75
Parallel I n Serles Out Synch Shlft Reg..
5.75
t
. . . . . . . . . . . . . . 5.75
8 Bit Shlft Reg.. S h ~ fR~ghtlleft
Same as 74198 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.75
MOS 64 x 7 x 5 ASCl Character Generator - generates 64
alpha.numeric characters on a 5 x 7 matrlx of lamps (or on
aCRTl . . . . . . . . . . . . . . . . . . . . 525.00
U Texas Instruments keyboard . . . . . . .
T.I. SN25391. SN26392 Dr~vers.4 required
[3All parts for clock generator . . . . . . .
fl Readouts. eight required . . . . . . . . .
13 Complete package, except battery . . . . .
The response to last montns
offer of the Sharp QT 8
calculator was overwhelm
tng. and w l t l ~ l n a short
perood of tome we ex
hausted tlielr entore stock lo
that tnls model IS no longer
avallable Because of thos
unprecedented response.
Sliarp has offered B & F a
spec181 quantlty purchase
on the model ELSA, wnlch
IS
the new pocket slze
verslon of the QT8 We can
offer t h ~ smodel at onlv a
few dollars more than the
2~7%discount on all orders for 100 or more integrated circu~ts.All
I.C. 's postpaid, with FREE air nwil on orders over S50.00. We
strive to ship I.C. 's by return mail. Free data sheets on all items.
S A N K 0 AUDIO AMPLIFIERS
.-
_.
We have made a fortunate pur.
-..--i
wJk~~idOh%%s.A~~t?
t?2z1:?;
can build your own aud~oamp
lflers at less than the prlce of
dlscrete components. Just add a
power supply, and a chan~sto
act as a heat slnk. Brand new
units, i n o r ~ g i n a l boxes,
guaranteed by B and F. Sanko
and the Sanko U.S. distributor.
Available in three slzes: 10 watts
RMS (20 watts music power), 25 watts RMS 150 watts M.P.1 and
50 watts RMS (100 watts M.P.) per channel. 20 page manu.
facturers instruction book ~ncluded.Sanko amplifiers have moved
so slmple and reliable, that they are bang used for ondustr~al
applications. such as servo amplifiers and wide band laboratory
ampl~f~ers.
I l 10 Watt RMS Amplifier
S 4.75
S14.75
U 25 Watt RMS A m p l ~ f ~ e r
$22.50
050 Watt RMS Ampl~foer
Sf-1025A
==---=-
..............
..............
..............
86
february 1972
. . . I for S 3.50
. . . . . S88.00
SPECIAL1 SHARP
MODEL ELSA CALCULATOR
.........
._..- - .-
. . . . $29.00
. . . . . S19.00
. . . l for S 3.00
. . . . . S 4.75
QT8. a remarkable buy at only 5192.50.
Don't forget. you can charge th~s. as well as other Items to
Mastercharge or BankAmerlcard. Fully guaranteed by Sharp
a n d B & F.
O Sharp electronic calculator, model ELSA . . . . . . . . . . $192.50
0 80 PAGE CATALOG
-
Free with any order or send $0.25
ALL ITEMS POSTAGE PAID I N THE U.S.A.
Charger W e l r o d . BnnkAmencard
- Mastercharge - S10.00 min.
B. & F. ENTERPRISES
Phone (6171 532 2323
P.O. Box 44. Hathorne, Massachusetts 01937
More Details? CHECK-OFF Page 94
-
NOVICE CRYSTALS
free f l er.
Electronics. Umatilla. Florida 32784.
Nat Stinnette
AUDIO FILTERS: Knock down that background
noise. KOJO SSB. AM and CW filters do the job.
Write for free brochure and see how serious DX
boys hear them. KOJO. Box 7774. 741 E. Hiah.
l a i d Ave.. Phoenix. Arizona 85011.
-
SERVICE AND USERS MANUAL for the Solar Cap.
acitor Analyzer. Not a reprint. $3.00 postpaid.
James Fred. Cutler. Ind. 46920.
-
JENNINGS W C UCS-375, complete with turning
head. spin knob. counter. limit stop. coupling
tested at 14 kv DC/AC
ostpaid $25.00. W6YO.
1416 7th Avenue, ~ e l a n o :l a l i f . 93215.
WWV, CW. R r r Y tone to logic decoder. Educational
includes eight epox PC boards, plans, hardware.
$4. Hornung. K ~ B H ( 1630 Bowling Lane. San Jose.
California 95118.
ROCHESTER, N. Y. is again Hamfest. VHF meet
and flea market headquarters for the largest event
i n the northeast, May 13th. Write WNY Hamfest.
Box 1388. Rochester. N. Y. 14603.
I
10 Peru St., Plattsburg, N.Y. 12901
- -
'
-
-
Hundreds
Dollars
1'roff.sional equipment fr<,rlt famous manuf ~ c t t ~ r c r \Ens).
.
step by step illr~\lratedinstnlcti~~ns,
n<>spvctnl 11101s required. Snvr I I P 111 757". This
hnnrll,r,<~k i s n must for every hr~nic~owner
end husinessn1;ln. Jt~st$ 1 cnsh, check or h1.O.
Write W l J F T
WANTED: R389, R390. R390A. R391, R220. Racal
and 51S1 recelvers. SWRC. P. 0. Box 10048.
Kansas City. Missouri 64 111.
ALARM COMPONENT DISTRIBUTORS
WORLD OSL BUREAU - See ad Dane 92.
-
33 NEW HAVEN AVE.. DEPT. HR
MILFORD. CONN. 06460
. -
WANTED #I95154 GEARSHIFT for M,odel 28 ASR.
Larry Kleber. K9LKA/W9CPD, Belvtdere, Illinois
61008.
RUBBER STAMPS: Your call i n %-inch letters.
$2.00. Call plus name and address. $4.00. Postpaid. Ellis Enterprises. Dept. W. Box 3007. Anchorage AK 99501.
-
-
TECH MANUALS
$6.50 each: URM-25D. TS-J4A/
AP. TS-497B/URR. R.274/FRR, SP.600JX. LM-21,
OS.OC/U. CV.59lA/URR.
BC.639A. Hundreds m,ore
in stock. S. Consalvo. 4905 Roanne Dr~ve.Washtngton. DC 20021.
- -
1971 Handbook fk Catalog
-
TELETYPE #28 LRXB4 reperforator-transmitter "as
is" $100: checked out $175. Includes two 3 speed
gearshifts. Alltronlcs.Howard Co.. Box 19. Boston.
Mass. 02101. 617-742-0048.
-
FIRE & BURGLAR ALARMS
HELP: Will pay any reasonable price f o r information o r manual for Racal Models RA6217A and
RA6366A. Barry J. Buelow, WAORJT/KH6. PSC 3.
Box 4613. APO SFC 96553.
CASH FOR PC BOARD. All types of copper laminate wanted. 20 pounds or more. Bob Miller.
WABKGE. 2264 Welch. Stevensville. Michigan 49127.
-- - -
I
YEAR-END SPECIALS
All checked and operating unless otherwise
noted. FOB Monroe. Money back (less shipping)
if not sattsfied.
-
NE Eng 14-20C Universal Counter-Timer. Basic
8-di it Nixie readout.
range 10hz-10mhz.
Checks frequency. p e r i o z etc. Similar t o
HP524C but with greater range of controls.
. Unchecked and without time standard
b"t complete with all tubes, Nixies, manual.
139
.
WANTED JOHNSON 6 and 2M Thunderbolt In m i n t
condition also ~ e n r 4K.
y ~ State cond. and price i n
first letter. Bill Smitherman. Rt. 2, East Bend, H.C.
27018 - 919.699-8699.
Same as ab
SWAN SW240. mint. $149 o r trade f o r DX6OB plus
$100. WA6LML. 26760 Shadowwood, Palos Verdes
Pen, CA 90274.
Any counter above wlth 1 plug-in ran e extender (choice of 10-100mhz o r . 100-2f0mhz.
add 49
COLLINS 7 5 5 1 Serial 3328 and 32s-1 Serial 2748.
Very good. Both for $600. Cash and Carry. H. K.
Monroe, 725 Caldwell, Piqua. Ohio 45356.
FOR SALE: R-390, cabinet, manual. $450. Gonset
3-6M.. 3065 Linear, $100. Paul Haczela (KZBQO)
8 Yale Place. Armonk. N. Y. 10504. 914.273-9067.
58200 Heathkit Kilowatt Linear $150. 415.593-7369.
W6KJG. 1120 Furlong. Belmont, Calif. 94002.
-
SELL OR TRADE for 2 meter equipment: Mobile
6 meter FM GE Progress Line Transistor supply.
100 watt output. Very clean on 52.525. With
manual, two frequency head, all accessories.
Daniel Vernier. 19741 Broadacres. Mt. Clemens.
Michigan 48043. 313.79143364.
-
YOUR AD belongs here too.
per word.
Non-commercial
Commercial advertisers write
for standing ads not changed
Commercial ads 256
ads 10C per word.
for special discounts
each month.
More Details? CHECK-OFF Page 94
ime
179
An counter
r0-220mhz
. ........................ 209
above wlth
- OTHER
2
plug-ins covering
add 89
COUNTER ACCESSORIES
-
UP524 series.
Solid-state hi-accur
plied above. St
Requires 6.3ac.
Original NE Eng
with oven. Minor additional circuitry required
55
for power, instructions included. .. .. .
Many other counters, frequency meters,, signal
generators and other items of test equipment.
(Send SASE f o r complete list)
GRAY Electronics
P. 0.
941 Monroe, MI 48161
Box
Specializing i n used test equipment
february 1972
87
NEW SSB MINIATURE CRYSTAL FILTERS - MadeU.S.A.
Wrtte us about our crystal filter needs
hodel WF-4 Model WF-8
~entei~rq.
9.0 MHZ
9.0 MHZ
Band Width at bdb
2.5 kHz
2.5 kHz
bOdb/bdb Shape
2.0 ( 4 5 / 6 )
1.8 max
WHEATUNDS Ultimate Rejection
45 db
100 db mln.
ELECTRONICS In/Out Termination 1 2 0 I? 140 R
P. 0. BOX 343 PRICE
$18.95
$26.95
ARKANSAS CITY
Matchlm Cmtalr USB (8998.5 kHz1
KANSAS 67005
or LSB (9001.5 kHz) $2.75 each
--,".m_
w--"..
RADIO AMATEUR
OPERATOR'S HANDBOOK
SPACE ELECTRONICS division of
MILITARY ELECTRONICS CORP.
WANTS TO BUY
A l l types o f r n i l ~ t a r y electron~c equipment and
parts. Call collect f o r cash offer.
1
76 Brookside Drive, Upper Saddle River
N e w Jersev 07458 (201 327-7640
I
VARACGRS
and VVC'S
for At~~atrur
Rad~oSewlce In Voltage
Controlled Osc~llators, AFC, remote
tun~ng, variablr Itlters . .
try the
NEW WAY to TUNE.
write for data sheets
.
I
I
-
EASTRON CORP.
-7.
25 Locust St., Haverhlll, MA 01831
CLUBS
WRITE FOR OUR
SPECIAL CLUB OFFER
HAM RADIO
GREENVILLE, NH 03048
-8c.-",
NEW!
for your operating
convenience
I
43XA
RADIO AMATEUR OPERATOR'S HANDBOOK
$64.95
4--
POSTPAID
432 MHz CONVERTER
Ideal for DX. FM and ATV
Very Low Noise
Choice of Input and output frequencies
6 Silicon Translstom
AC Power Suppl
Die Cast Cabinet
Precision ICM 5th 6 v E
tone Crystals - Write for FREE CATALOG o r
Order D ~ r e c tfrom
P. 0. BOX 112
-
JAN EL
SUCCASUNNA. N. J.
LABORATORIES
07876
(201) 584-6521
by The Staff of Data Publications
A very useful collection of operating data
for the operating table of any HF amateur station. Contains many tables, maps
and charts outlining much valuable information such as GMT conversion to
local time, Amateur Prefixes, Call Area
breakdowns for many countries,
Zone
Boundaries, a Countries Worked Chart
perfect for 5 Band DXCC and many more
pieces of important data.
ONLY $1.95 Postpaid
order today from
corn,BOOKS
Greenville, N e w H a m p s h i r e
88
f e b r u a r y 1972
More
03048
Details?CHECK-OFF Page 94
More Details? CHECK-OFF Page 94
february 1972
89
W
'OUALITY
7-SEGMENT INCANDESCENT
rEnDouT:
COMPONENTS.
SEMI
I31 SN7490N
l7i ~I~C ' Sc TOTAL
s r *13?E
~
-7:
DECIDIGIT
Counter Buildin
INcLuozr :
only S8.95
7-stG%~~:%!cI~
SN7447N DRCOfR W l M l
SN74PON
CQHIIR
m u r
CIRCUITS A N 0 NEW
or STAMP
IDEAS TOO!
112,
NEW CATALOG INCLUDES
THREE NEW
COMPLETE KITS
INSTRUCIIONS
SEND
PO BOX
- K I T S:
SPEC SHEETS I N C L U D E D
GOODYEAR, ARIZ.
85338
5/g/1a//d/~~
CX-7A
N
e
w "A" r n c d e l N o w A v a l l a b l e
Still $ 2 1 9 5 - G r e a t N e w R e i ~ a b l l l t y
I
Central New York Specialty Headquarters
FM by STANDARD COMMUNICATIONS
High Power by EHRHORN
Quality-Selected Used Ham Gear
I Write for listing, updated twice monthly I
I
CFP ENTERPRISES
10 Graham Road West
Ithaca, New York 14850
607-257-1575
B R O A D B A N D A M P L I F I E R S a t a p r i c e y o u c a n afford
The BBA-1 series offer high
gain over the HF to UHF
region with Noise Figures as
low as 3dB max. BBA-1PB cov.
ers 3 0 to 400 MHz wilh 17dB.
P h o n e l w r l t e D o n Payne, K 4 1 D
for a b r o c h u r e a n d b ~ trade-ln
g
on y o u r gear
PAYNE RADIO
B o x 525 Sprlngfleld, T e n n e a s e
d a y s ( 6 1 5 ) 3 8 4 - 5 5 7 3 n ~ g h t s( 6 1 5 ) 3 8 4 - 5 6 4 3
.. -
HIGHEST
W E PAY
maximum Nolse Figure of 3.0
dB. For less critical use order
the BBA-1 which has the same coverage as the BBA-IP but
with slighlly reduced UHF gain and higher Noise Figure. They
are all a bargain! BBA-1PB. BBA.1P $45.00, BBA-1
530.00 FOB Baltimore
-
PRICES FOR ELECTRON
P.O.
-
R A D I A T I O N D E V I C E S CO.
B o x 8450. B a l t i m o r e , Md. 21234
TUBES AND SEMICONDUCTORS
HARD-TO-FIND
H & L ASSOCIATES
L,..!.
I",<,
ELIZABETHPORT INDUSTRIAL PARK
III.,,,
..,,,~,,w,rv
PRECISION TOOLS
1 7 0 0 ,I, .-I,I,.~
\!r!lllKr5,
,
",,<,U,Il ' ~ , > I L ' ' 5 ,
-2%
Q
tool^, o!>t8rr3l ~ : ~ ~ ~ t t<>(,l
l ~ #kt15
~~r##I,
c.tsrr. Alw, ~ o c l t 1 d v 5foctr p.811~5
01
u\t.1111 "Tool T ~ p 5' l o all! In tool rclcrt~all.
rc1.t~
ant!
ELIZABETH. N E W JERSEY 07206
(201) 3514200
F-
,i.
-..
CURTIS
..
.
EK
C.[ .
4114
DELUXE KEVER
5174 95
E l 4OZPIOGRAMMABLE KEVER
WRITE
90
1
115 Vnc I N O t l 2 V d c
R E A D J A N I911CO REVIEW OF SIMILAR
e
Inii?,nl
1
a
Tubes New Sllrplur 506 ea. ILC6, ILH4, ILN5, IT4, IP39,
2A3 2C52 387 3 0 6 5Y3 523 6AC7 6AK5 bH6
606' 6J5 ' ~ 6 ,b ~ 7 ,k ~ ~ 7 . ' 6 ~ ~6SK7'
7 , ' 6SL7 ' 6 ~ ~ 7 :
6 5 9 f 6 ~ b1 2 A l 7 12SG7 26Ab 8 4 56f0. Transistors
35,- 'ca. i ~ 1 3 0 5 ,' ~ ~ ~ 6 5 i~2~, f 6 5 i 6ARC
.
R19 RCVR
118-148 MHz with schemallc $14.95. RTTY tertn~nal unlt
FSTU-1A 534.95. Catalogue 1 0 c .
FRANK ELECTRONICS
407 R l t t e r Rd.. H a r r ~ s b u r g . P A 17109
A L L THE FEATURES V O U V E ASKED FOR
&
1-icC
r r y .
FOR BROCHURES
E L E C ~
MVICES
-.,dl.
avmv.s*vor*
february 1972
c.,,,~.~.
rpo
.
rrr *IS u n r
More D e t a i l s ? CHECK-OFF Page 94
OPEN HOUSE!
Washington's Birthday Weekend
FEBRUARY 18, 19 and 2 1
FREE
FREE
coffee and Doughnuts
Frequency, Deviation & Sensitivity
Checks of your FM Gear
FREE PRIZES
NEW GEAR
CLEGG
DRAKE
HENRY
HEIGHTS
SONAR
REGENCY
JOHNSON
DYCOMM
AUCTION
USED GEAR
DISPLAYS
STANDARD
MOSLEY
CUSHCRAFT
ANTENNA SPECIALISTS
DEMONSTRATIONS
FM TALK I N 146.94
BRIS TOL RADIO
4 2 0 HOPE STREET
BRISTOL, R. 1. 02809
401-253-7105
EARLE
- WlRGG
More Details? CHECK-OFF Page 94
MIKE
- KlOHE
GLEN
- W2CXX/1
february 1972
91
0.9 at 133 mhz, 5 at 538 mhz, 4% at 778 mhz, 7 at 1
ghz. The receiver Is actually a 30 mhz I F ampl. with all
that follows including a diode meter for relative signal
strengths: dn atten. calibrated In 6 db steps to -74 db
followed by an AVC po$ition: Pan. Video & AF outputs!
switch select pass of f200 khz or1*2 mhz; and S E L E C ~
AM or FM ! With Handbook & pwr-input plug, all only
375.00
30 mHz Panadapter for the above
..
129.50
REGUL. PWR SPLY FOR COMMAND. LM. ETC.
PP-lOb/U. M~tered. Knob-adjustable 90-270 v uo to 80
ma dc; also select an AC of 6.3 v 5A or 12.6 v 2% A or
28 v 214 A. With mating output plug & all tech. data.
Shw. wt. 50 Ibs.
. . .19.50
BARGAINS WHICH THE 'ABOVE WILL POWER:
LM-(") Freq. Meter: 125-20 MHz, .Ol%, CW or AM, with
serial-matched calib. book, tech. data, mating plug. Ship~ing
FACTORY FRESH IC'S A T BARGAIN PRICES
7400 7401 7402 7403 7404 7410 7420 7430 7440,
7451' and f454 dates dl1 30: each.' 7 4 4 i ~nix; driver
$1.60. 7442 BCO-to-decimal decoder $1.50. 7447 seven
segment driver 51.79. 7472 flip flop 50c. 7473 dual
flip flop 6 0 ~ . 7474 dual type D flip flop 6 0 ~ . 7475
quad latch 51.25. 7476 dual flip flop 65r. 7490 decade
counter 51.25. 7492 divide by 12 counter 51.25. 7493
4 bit binary counter 51.25. 7495 4 b ~ tL-R shift reg.
51 50. 74121 monostable niultivibrator 7 5 ~ .
LINEAR IC'S: 709C OP amp dip 60C TO-5 70d
741C OP amo din 75c
- . TO-5
. . R5c.
- ..
TRANSISTORS:
2N5134 scl~conNPN 7 for 51.00.
2H5139 silccon PNP 7 for 51.00.
Power Supply 110 volt AC Lo 5 volt OC $10.00
O~scounts offered on large orders. Many other parts
available. Send post card for free catalog. Orders less
than 510.00 add 2 5 t post. & handling. Above 510.00 ppd.
DIGI-KEY
P.O. BOX 126. T H I E F RIVER FALLS. MN 56701
NEW 2M PREAMPLIFIER
. ..
R23A/ARC5 Command 9-5'er 190-550 KHz, exc. cond. 16.95
A.R.C. R22 Command rNr 540-1600 KHz, exc. cond 17.95
A.R.C. R15 (MIL R-509) command, 108-135 MHz, new 27.50
-
-~
1
I
12 vdc powered
27 db gain (approximately)
noise figure 2.5
will bring most receivers
to .1 av sensitivity
without appreciable noise.
Metal case. ONLY $17.95 ppd.
CRAWFORD ELECTRONICS
302 West Main, Genoa, IL 60135
--
T H E MlLLlWATT
"
NATIONAL JOURNAL OF QRPP
All about under.fcve watt ham radio
Construction Projects
Operating News
WAS & OXCC QRPP List~ngs Lcq Reports
RATES: $3.00 (six issues/year) 53.40 1st Class Mail.
Reprints: Vol. I-$4.00
Vol. 11-53.50
(both 57.00
plus subscription-$10.00!
SASE for info 11
ADE WElSS KBEEG
117 Central F-10, Acton, MA 0 l l d
..
SlOiOI.0
YOWL : r i
bO*IYL,..,,I
r
IPr5"
*I41
..'
. .
V i s i t Roger Miner's S u r p l u s Electronics, 2 4 6
N a u g a t u c k Ave.. Milford. Conn. Ph. 877-0555.
N i g h t s 7 p m t o 1 0 p m a n d a l l d a y Saturday.
DRAKE TR.3 W/PS-$350. Collins 75S1 W/
NBR-$300. HEATHKIT SB-200.5165. SB-620$65. OP.l Scope-$90. H.P. 460b Wideband
amp.-$25, 210a Sq. W. Gen.-$15. 522b-$ 120.
AMPEX FR-1100 Stereo tape rec..S350. 4lOOOA Filament Trans 7.5 vac P 42 amps.
w ~ l l r u n a pair.$30.
A m p f ~ l a m e n t chokes
3 - 3 0 m c s 3 0 a m p s $9.50. Johnson 15 a m p
rotary ind. 27uh.$25. H I G H POWER HEADQUARTERS I N T H E NORTHEAST. COME I N
A N D SEE U S
KlDQV.
3 0 2 H Passaic Avenue
Stirling. N. J. 07980
C A L L 201-647-3639
-WORLD
(IS1 B U R E A U 1
THE ONLY OSL BUREAU
to handle a l l
of y o u r QSLs t o anywhere: next door, t h e
next state, t h e next country, t h e whole
world. J u s t b u n d l e t h e m u p (please arrange
alphabetically) a n d s e n d t h e m t o u s w i t h
p a y m e n t o f 5C each.
5200 P a n a m a Ave.. R k h m o n d . CA USA 94804
-
92
february 1972
More Details? CHECK-OFF Page 94
CIRCUIT
BOARDS
i n 10
Minutes
TmTEit*
?
rm.
Ar A GU-.
CALL-IDENT
8
10-MINUTE STATION
CALL REMINDER
--
..
..
..
Pressure Sensitive Copper Foil
Tape and Sheet
-
-
N o Chemicals
N o Mess
N o Lavout Restrictions
Full Instructions
Simple Circuit Changes
Flexible
Conforms t o any surface shape
Use for Crossovers
Either insulate wlth
Teflon or Mylar or use other side of board.
-
.
10-minute r e ~ e o t i "
n otimer buzzes w o r n l n o., lo sol-~n>.vour
,~~
call letters. Wolnul or ebony ploslic case. 4"H. 73/r"W,
4"D. 110V. 60 cy. One Yeor Guarantee. Mode in U.S.A.
At Yaur D r a l m r . er DIRECT F R O M
-
5 feet 1/16rr o r 1/8n wide
100 feet 1/16" o r 1/8rf wide
-
.................. s.60
..................$9.95
Sheets 61' x 121'
$2.50 each
o r 5 f o r $9.95
TELEGRAPHERS WANTED
-
For membership In
Morse Telegraph Club, Inc.
-
Order Now
Non-prof11- H~slor~cal Fraternal
ncludes subscripl~onto dots & Darhes
Dues $2 per annurn
Write: James E. Smith. GS&T
P.O. Box 70
Division of PHASE CORPORATION
315A Boston Avenue
Medford, Mass. 02155
FEBRUARY BIRTHDAY VALUES!
IT'S BIRTHDAY WEEK A T BARRY'S
George on the 22nd - Barry on the 23rd
JUMBO BIRTHDAY SALE
FEBRUARY 19, 21-26
-
...
TUBE HEADQUARTERS OF THE WORLD
TREMENDOUS STOCKS OF TUBES. Advise
us of your tube needs for immediate quotations. We also purchase UNUSED tubes and
new and used equ~pment.THOUSANDS OF UNADVERTISED "GOODIES" VISIT OR CALL!
-
ROBOT SLO SCAN TV Camera Mod. 80 $465.00
ROBOT SLOW SCAN N Monitor Mod $495.00
F1.4 MACRO LENS
$60.00
2 METER FM EQUIPMEN'T:
DYCOMM BRICK BOOSTER/For TR.22 1 W.in/
20 W out.
$69.95
DYCOMM SUPER BRICK BOOSTER 1 Win/
35 W out.
$99 95
DYCOMM BLOCK BOOSTER 10 W.ln/ 50 W out
$89 95
DYCOMM "10-0" Moblle AmD. 10 W.in/ 100 W
out.
$185 00
DYCOMM DIVIDE BY TEN PRESCALER. 10 240
MHz.
$ 89 95
DRAKE ML-2 2 METER FM TRANSC~EIVER AC/
DC 12 Ch 3 s u p p l ~ e d
$379 95
DRAKE TR-22 WALKIE TALKIE 2 Meter FM 6
Ch
3 s u ~ ~ l t e dwlth
,
Mlke. Case. Cords and
N ~ c a dBatteries.
BARRY CAN SUPPLY anv o f the c o m ~ l e t eline
of Drake or Dycornrn Products.
SONA LABS 10 CHANNEL SCAN.O.MATIC 2
Meter FM or Hlgh Band Receiver. Hlgh Band
Model 22.65A $ 149.95. 2 Meter FM Model 22658 $ 149 95 (Crvstals $5 00 each).
PEARCE SIMPSON 25 WATT 2 METER FM
TRANSCEIVER, 6 Channel, two suppl~ed. DC:
only at
$249.95 AC/DC at $299.95
COLLINS 32V.1 Transrnltter, Wrlte.
.
.
More Details?CHECK-OFF Page 94
TEN-TEC: RX.10 RCVR @ $59.95: S.30 Signalizer o $49.95: PM-3A XCVR @ $79.95: PM-2B
XCVR
$65.95.
VHF HAMMARLUND H i 7 0 A 160 t o 2 meters
new cond S375.00: Hs.170 160 t o 6 meter;
clean $275.00.
RCA 'AN/SRR 11 V.L.F. Receiver 14 t o 600 khz.
Good cond
$175.00
TECHNICAL MATERIAL CORP. GPR-90-RXD Gen.
era1 and Hamband coverage, a hlgh quallty
RCVR that covers .54 t o 31 5 mhz. Wlth side.
band adapter.
$595 00
JOHNSON VIKING 500 XMTR.. 500 watts 80
t h r u 10 meters. wlth pwr. sply. clean. $25000
HALLICRAFTERS HT-37 80 t h r u 10 meter cw/
ssb Xmtr clean.
$125 00
YAESU F ~ D X400 (80 t h r u 10 meters. AM. CW
and SSB new cond
$295 00
FDDYSTONE 840C Deluxe General Coverage
$ 125 00
Rcvr. 480khz t o 70mhz. Clean
NATIONAL NC-183D General Coverage Rcvr.
clean
$60 00
HP 130C OSCILLOSCOPE. rack mount Exc
cond.
$250 00
BARRY ELECTRONICS
F;/cc~troriic7'rrhr.s G E(/rtiprrict~t
512 BROADWAY
NEW YORK. N. Y. 10012
212 WAlker 5 7 0 0 0
f e b r u a r y 1972
93
q
check-off
~dvertsers
. . . for literature, in a hurry we'll rush your name to the companies
whose names you "check-off"
INDEX
-Alarm
-American Crystal
-Arizona
-B & F
-BC
-Baker & Winnay
-Barry
-Bristol
-CFP
-Cir-Kit
-Circuit
Specialists
-Corncraft
-Corntec
-Crawford
-Crystek
-Curtis
-Data
-Digi-Key
-Drake
-E-S
-Eastron
-Ehrhorn
-Eimac
-Environmental
-Frank
-Gateway
-Gray
-H & L
-HAL
-Heath
-Henry
-HyGain
--International Crystal
-Jan
-Jane1
-Jaross
-Jensen
-Juge
-Justin
-KW
-LA
-Linear
-Meshna
-Micro-Z
-Miltiwatt
-Morse
-Newtronics
-Palomar
-Payne
-Pennwood
-Pickering
-Poly Paks
-RP
-Radiation
-Callbook
-Radio Constructor
-Robot
-SCF
-Savoy
-Signal/One
-Space-Military
-Spectronics
-Standard
-Structural Glass
-Surplus
-Swan
-Ten-Tec
-Tri Rio
-VHF Specialists
-Van
-Vanguard
-Vero
-Weinschenker
-Wheatlands
-Wolf
-World QSL
February 1972
Please use before March 31,1972
Tear off and mail t o
HAM RADIO MAGAZINE
Grecnville, N. H. 03048
- "check-off"
NAME.......................................................................................................
CALL...........................................
STREET...........................................................................................
C I N...........................................................................................................
STATE.. ...........................
ZIP.................................................
94
february 1972
ATV Research ........................................................................ 90
Alarm Component Distributors .................... 87
American Crystal Co. ..................................................
78
Arizona Semiconductor ..............................................90
B & F Electron'
86
BC Electronics
78
Baker & Winna
92
Barry Electron
93
Bristol Radio
91
90
93
84
31
88
92
76
90
66
92
.-
77
76
.........................88
Eastron Corp. ............................
.
.
.
Ehrhorn Technological Operations, Inc. . . . . . 71
Eimac Division of Varian ..................... Cover IV
Environmental Products ................................ 48, 49
Frank Electronics ..........................................................90
G & G Radio Electronics ......................................
75
Gateway Electronics Corporation . . . . . . . . . 72
Goadheart Co.. Inc., R. E. ...................................... 92
Gray Electronics .........................................87
H & L Associates ......................................................
90
HAL Devices .............................................................
82
Heath Co. ..................................................................
65
Henry Radio ..........................................Cover Ill
Hy-Gain Electronics Corp. ............... 5. 19. 80, 81
International Crystal Manufacturing Co. .... 73
74
88
72
90
89
76
87
LA Electronix Sales ............................... 95
Linear Systems. Inc. .................................................
37
78
76
92
93
1
72
90
93
68
64
74
90
68
Radio Constructor ................................ 78
Robot Research ............................................96
SCF Corp
70
Savoy Electronics. Inc.
69
S~gnal/One
Cover II
Soace-M~lltary Electronics
9
The NEW GALAXY 550A
Now available for immediate delivery
at our new low price
ONLY $495
SEE LA
FOR
THE TOP TRADE-INS IN THE WEST
Electronix Sales
23044 S. CRENSHAW BLVD., TORRANCE, CALIF. 90505
Phone: (213) 534-4456 or (213) 5344402
HOMEof LA AMATEUR RADIO SALES
I
I
BONUS COUPON
A VX35C VOX and A CAL-250-25 CALIBRATOR
Included FREE with evenj Galaxy 550A from LA Electronix
1
I
A $55.00 VALUE!
More Details? CHECK-OFF Page 94
february 1972
95
N o w with t h e purchase o f a R o b o t SSTV m o n i t o r
only, R o b o t will make y o u a free personalized
SSTV tape t h a t w i l l enable y o u t o transmit a video
camera.
signal
without having
own an
After you havepurchased your ROhot
monitor, just mail us the call sign card, photos,
drawings, etc., that y o u want o n y o u r tape, and
we w i l l make up a five-minute tape for y o u (reel
o r cartridge) and send i t t o y o u by r e t u r n mail.
Y o u then simply play the tape o n an audio tape
recorder that is plugged i n t o the m i c jack o f y o u r
transmitter o r transceiver, and y o u are transmitting
an SSTV video signal.
Now, for just $495 (the cost o f the R o b o t SSTV
Monitor alone) y o u can j o i n the m a n y amateurs
w h o have already made great progress towards
their WAC, and WAS certificates ant1 working their
first 100 countries o n two-way SSTV.
If you are alredy
operating
SSTV, you wil
be
interested t o k n o w that we are preparing a directory of SSTV operators. Send us a post card and
we wil
include your call in our directory and
send you acopy,
F o r complete information on Slow Scan
and
o u r SSTV equipment, write:
ROBOT RESEARCH INC.
7591 Convoy Court
San Diego. California 92111
Phone 714-279-9430
See t h e complete line o f R o b o t SSTV equipment at y o u r nearest dealer.
Blnningham. Ala. 35233. James W. Clary Company, 1713 Second Avenue South, (205) 322-2486 Anaheim, Calif.
92804, Henry Radio Company, 931 North Euclid, (714) 772-9200
Los Angeles, Calif. 90064, Henry Radio
Company, 11240 West Olympic Boulevard, (213) 272-0861
Oakland, Calif. 94607, Amrad Supply, 1025
Harrison Street, (415) 451-7755
Denver, Colo. 80202, CW Electronic Systems. 1401 Blake Street, (303)
244-5523 Mlaml, Fla. 33137, Amateur Radio Center, Inc., 2805 NE Second Avenue, (305) 374-4101 Honolulu,
Hawaii 96803, Honolulu Electronics, 819 Keeaumoku Street, (808) 949-5564 Reading, Mass. 01867, Graham
Radio Company. 505 Main Street, (617) 944-4000 Muskegon, Mich. 49441, Electron~cD~str~butors.
Inc., 1960
Peck Street, (616) 766-3196 St. Louis, Mo. 63132, Ham Radio Center, 6342 Olive Boulevard, (314) 993-6060
Amsterdam, N.Y. 12010, Adirondack Rad~oSupply, 185-191 W. Main Street, (518) 842-8350 New York, N.Y.
10012, Barry Electronics, 512 Broadway, (212) 925-7000 Asheville, North Carolina 28801, Freck Radio Supply,
38 Biltmore Avenue, (704) 254-9551
Cincinatti, Ohio 45231, Queen City Electronics, 1583 McMakin Ave.,
(513) 931-1577 Cleveland, Ohio 44112, Amateur Electron~c Supply. 17929 Euclid Avenue, (216) 486-7330
Dayton, Ohio 45404, SREPCO, 314 Leo Street, (513) 224-0871 Trevose, Pa. 19047, Hamtronlcs, 4033 Brownsvllle Road, (215) 357-1400 * Fort Worth, Texas 76110. Ed Juge Electronics, 3850 South Freeway, (817) 926-5221
Spokane, Wash. 99206, HCJ Electronics, E. 8214 Sprague, (509) 924-2343 Milwaukee, Wisc. 53216, Amateur
Electron~cSupply. 4828 W. Fond du Lac Avenue, (414) 442-4200 CANADA: Fredericton. N.B.. Audio Lectronics
Ltd., 79 Prospect Street. (506) 454-3380 Toronto, Ontario, VE Amateur Radio. 3768 Bathurst Street, Downsview,(416) 636-3636 * Montreal, Quebec, Payette Radio Company, 730 St. Jacques. (514) 866-6681.
Butler, Mo., Henry Radio (816) 679-3127
96
february 1972
M o r e Details CHECK-OFF Page 94
THE MOST EXCITING RECEIVER AND TRANSCEIVER TO ENTER THE AMATEUR SCENE I N RECENT YEARS. THE
KENWOOD R-599 SOLID STATE RECEIVER AND T-599 HYBRID TRANSMIITER HAVE ESTABLISHED NEW STANDARDS OF PERFORMANCE, RELIABILITY, FLEXIBILITY, STYLING AND VALUE.
THE R-599 RECEIVER: .5 microvolt sensitivity
(amateur bands 1.8-21.0 MHz) * Dial readout
to % kilocycle Special detectors for SSB, AM,
and FM
Transceive operation with T-599
Built-in 100 kc and 25 kc crystal calibrator
Provision for two
Built-in 500 cycle CW filter
meter and six meter coverage with optional accessory self-contained converters
Advanced
"Space-Age" styling
Adjustable threshold
squelch Only $349.00
S599 Speaker $16.00
*
*
THE KENWOOD
TS-5 11S
TRANSCEIVER
-rhe ~~~~~~d 1s-511s isa
five band SSB and CW transceiver packed with power
and performance.. .offering
features never before available in its price range. For
example: built-in VOX, crystal calibrator, noise blanker,
receiver incremental tuning,
1 kHz frequency readout, 8
pole filter, stable FET VFO,
dual convenion and accessow CW filter.
THE T-599 TRANSMITIFR: Clear, stable, selectable side-band, AM and CW
4-way VFO Flexibility plus Receiver Incremental Tuning (RIT)
when used with the R-599
Amplified ALC
Built-in VOX
Full metering, including cathode
current, plate voltage, ALC and relative Power
Output Built-in CW Sidetone monitor and semiautomatic break-in CW Built-in power supply
MaximuniTVI protection* Employs only 3 vacuum tubes
Only $395.00
*
*
*
...........................
...........................
...........................
...........................
iiiiiiiiiiiiiiii;fii;iiiiii
...........................
;;;;iii;;iii;;;;;;;i;;;ii;;
...........................
...........................
...........................
iij;ii;iiiiii;i;iiii;iiii;
FREQUENCY RANGE: 10,15, LO,
40 & 80 meters (Amateur Bands)
0 MODES: LSB, USB, CW 0
INPUT POWER: 500 watts PEP,
300 watts CW nominal. 0
SENSITIVITY: 3.5-21.6 mHz band;
0.5 uv S/N 10 db 28.0-29.7 mHz
band; 1.5 uv SIN 10 db and less
than 100 cps frequency drift per
30 minutes after warm-up 0
SELECTIVITY: SSB more than 2.4
KC (at f, tlb) with 2 to 1 slope ratio
CW more than 0.5 KC (at 6 db) o
A.F. OUTPUT: more than 1
watt (10% distortion) 0 TUBE &
SOLID STATE COMPONENTS: 10
Tubes, 1 IC, 37 Transistors,4 FET,
52 Diodes 0 PRICE: $415.00
PS 5115
Power Supply w ~ t hbu~lt-in
speaker $105 00
CW-1 F ~ l t e $39
r
00
VFO 5 s s $105.00
keep Henry Rad5ots new
r.?traT3.newarrmpflifier
Henry Radio beat the blower noise problem by eliminating it. In their quiet, compact, rugged and reliable 2K Ultra
Linear Amplifier, anode heat is silently conducted to an efficient heat sink. No more blower. No more blower noise. No
more annoying problem.
Two EIMAC conduction cooled, high-mu 8873 power triodes are used in this very linear, state-of-the-art amplifier to
provide 2 kW PEP input over the 3.5 to 30.0 MHz range.
Operating in cathode driven service, these tubes typically
provide high power gain (greater than 13 decibels) in combination with low, low intermodulation distortion (3d order
products better than -35 decibels below one tone of a twotone test signal). These excellent characteristics of the 8873
may be utilized up to 500 MHz.
With Henry Radio, you know quality counts. And they
know you can't do better than EIMAC. For full
specifications on the 8873 and its sturdy companions, the 8874 and 8875, write to EIMAC
Division of Varian, 301 Industrial Way, San
Carlos, California 94070.
( I V ~ S I O ~
varian
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