Yamaha T-7 Owner's manual

Yamaha T-7 Owner's manual
 'S MANUAL
OWNER
ng we
fess
Thank you for purchasing the YAMAHA T-7 AM/FM stereo tuner.
This sophisticated tuner comes with a full range of features for the ultimate
in audio performance. It provides exceptionally accurate music reproduction
under even the most demanding reception conditions.
Please read these instructions through before operating your tuner and re-
tain this booklet for reference so as to ensure that you will gain the maximum
from your T-7 through many years of use.
CONTENTS
CAUTION: READ THIS BEFOREOPERATING YOUR T-7................... 2
CONNECTION DIAGRAM. «oe 3
CONNECTIONS. aaa aaoaen rara enana 4
NAMES OF THE PARTS AND THEIR FUNCTIONS... ................... 5/6
RX MODE/SIGNAL QUALITY INDICATOR/
MULTIPATH INTERFERENCE. . ..... a anoaren0 7
PRESET TUNING/ MEMORY BACKUP POWER SUPPLY ..... ss 8
TROUBLESHOOTING. ...... aa aaaaoareonea . 9
SPECIHFICATIONS вене енвениввеваввеоевоне, 10
IMPORTANT
Please record the serial number of your unit in the space below.
Model: 1-7
Serial No.:
The serial number is located on the rear of the cabinet. Retain this
Owner's Manual in a safe place for future reference.
Special Instructions for British Model
THE WIRES IN THE MAINS LEAD ARE COLOURED IN ACCORDANCE
WITH THE FOLLOWING CODE:
Blue: NEUTRAL
Brown: LIVE
As the colours of the wires in the mains lead of this apparatus may not
correspond with the coloured markings identifying the terminals in your
plug, proceed as follows. The wire which is coloured BLUE must be
connected to the terminal which is marked with the letter N or coloured
BLACK. The wire which is coloured BROWN must be connected to the
terminal which is marked with the letter L or coloured RED.
WARNING
To prevent fire or electrical shock, do not expose this tuner to rain or
moisture.
CAUTION: READ
YOUR T-7.
The T-7 1s a sophisticated AM/FM stereo
tuner. To ensure proper operation for the
best possible sound reproduction, please read
this manual carefully.
Choose the installation location of your T-7
carefully. Avoid placing it in direct sunlight or
close to a source of heat. Also avoid loca-
tions subject to vibration and excessive dust
heat, cold or moisture.
Do not open the cabinet as this might resuit
in damage to the set or electrical shock. If a
foreign object should get i into the set, con-
tact your dealer.
To prevent lightning damage, pull out the
power cord and remove the antenna cable in
case of an electrical storm.
THIS BEFORE OPERATING
When removing the power plug from the wall
outlet, always pull directly on the plug; never
yank the cord.
Do not use force when using the switches
and knobs.
When moving the set be sure to first pull out
the power plug and remove cords connecting
to other equipment.
Do not attempt to clean the 1-7 with
chemical solvents as this might damage the
finish. Use a clean, dry cloth.
Be sure to read the “troubleshooting” sec-
tion for advice on common operating errors
before concluding that your T-7 is faulty.
Keep this manual in a safe place for future
reference.
If your T-7 has a voltage selector, check that
it is set to your local voltage before you plug
it in. If not properly set, unscrew the two
switch-guard retaining screws, and reset the
switch to indicate your supply voltage
(110— 130 V, or 220— 240 V). After setting
the voltage selector switch to the correct
voltage, replace the switch guard and attach
it with two retaining screws.
VOLTAGE SELECTOR =
Г 10V-130V 220v-240v
Switch guard Retaining screws
Fig. 1
External antenna
—
The AM loop antenna
may be removed and
placed at a distance
from the set.
AM loop antenna
CONNECTION DIAGRAM
CTN
FM T-type antenna
pl eee)
Qo т
7
Integrated amplifier
OMB on ui im ai rue
pn ae
A
AM antenna lead: if reception is poor
with the loop antenna, run a 5—10
meter insulated wire outdoors.
To Tuner or Aux. terminal |
“To Cassette deck LINE IN termina
U.S. € Canadian models
o
My ema mw
Flat twin-lead wire (300 ohms)
= cable plug —
Coaxial cable {75 ohms)
WARNING TO PREVENT F
FHIS APPLIANCE 1 RAMO
HAZARD. DDINOT EXPOSE
GME w A408 ET
SE ATTENTION-NE PAS ENLEVER LES VIS, LI
INSTRUCTIONS AU—DESSOUS DE L'APPA
CAUTION—00
SCREWS. SEE
VOULU
and reduced interference, grounding is
Into the earth.
L
Connect to AC power outlet. Do not connect
10 а switched outlet as continuous power is’
required for charging the memory back-up
battery.
A ground lead is not necessary for normal
reception, but from the point of view of safety
desirable. Connect a heavy wire t¢ a cold
water pipe or a grounding rod driven solidly
CONNECTIONS:
The 1-7 has two sets of output jacks for
connection to your stereo amplifier. Use the
cable supplied to connect from the “Fixed”
jacks to the Tuner input jacks of your
amplifier, being sure to observe the left and
right channel markings. Also make sure that
the connections are secure and that the con-
necting cable is not bundled together with
the speaker leads from the amplifier. Later, if
It is desired to match the output signal level
of the tuner to that of some other source
such as a turntable, change the cable to the
“Variable” jacks and adjust the control on
the bottom panel until equal volume is ob-
tained with the two sources. This should
eliminate having to adjust the volume control
when switching from one source to another.
Choose an FM antenna that is appropriate to
the local reception conditions. Consider the
distance from the broadcast station and pos-
sible interfering objects such as surrounding
tall buildings. In cases where there is a
strong signal from a local station, a portable
T-type antenna is usually adequate. Connect
the feeder wire to the 300 ohm terminal,
stretch the wire out tight, and turn to
obtain optimum reception. Attach to a
suitable support such as a wall.
In all but the best reception conditions, an
outdoor FM antenna is necessary for best re-
sults. Either 300 ohm flat twin-lead wire or 75
ohm coaxial cable may be used. In locations
where electrical interference is a problem,
coaxial cable is preferable. Refer to fig. 2 for
Instructions on installing the coaxial cable
plug.
Attaching the plug to the
coaxial cable (1) Remove the outer cover-
ing of the coaxial cable up to
Insert the center about 23 mm from the end,
conductor and slide the tightening
sleeve over the cable. insert
the center conductor of the
coaxial cable into its hole in
the plug section, place the
shield into the shield holder
and push in.
(2} Screw on the tightening
sleeve.
O Plug section
Shield holder
Center conductor
Shield
Quier jacket -— al 18
Tightening sleeve
Coaxial cable
In many cases it will be possible to get ex-
cellent AM reception with the attached AM
loop antenna. Attach the antenna leads to
the Gnd and AM Ant terminals and rotate the
antenna in its bracket for best reception.
The loop antenna may also be removed and
hung on the wall.
If necessary, an outdoor antenna may be
used for improved AM reception. Connect a
5— 10 meter length of insulated wire to the
AM Ant terminal and run it outdoors.
3 NAMES OF
THE PARTS AND
THEIR FUNCTIONS
© 9 © 9 ©
ED YAMAHA NATURAL SOUND AM FN STEREO TUNER T-7
Cm | ZZ —
FM N pra que It un He he inf a 186 ESE pri ; а 4 04 I a mn ES pray “e IEEE tpeater ire
ДАВИ = ! sha sóc 5 800 262 1660 50 pa do — Pe 1500, Cb —_—— =
Lever _ 0 _ _°0_ _ 20__ 0 __ >07
FOWER REG CAL BLENDFM-MUTE /OTS RX MODE FUNCTION FM MODE SIGNAL QUALITY
[4 | ñ Г N n | ох LOCAL STEREO | 20 | 40 ] SD | BO | 190
=a = Es rrr rr rrr Tre
© е © O © © e ® © ® Ф
O FM DIAL SCALE O PRESET TUNING BUTTONS O POWER
The received FM frequency is shown in 5 FM stations and 5 AM stations can be This isa push-on, push-off” type power
MHz (megahertz). memorized. When a preset tuning button is switch.
9 AM DIAL. SCALE
The received AM frequency is shown in
kHz (kilohertz).
© TUNING INDICATOR
The pointer shows the FM or AM frequency,
and 2 green LEDs indicate precise tuning by
lighting up with equal brightness. In cases
where the signal level is weaker than the
muting level, the LEDs will not light.
pushed, the corresponding station will be
Immediately tuned in.
© TUNING KNOB
This knob selects the desired broadcast sta-
tion. While looking at the Signal Quality
Indicator and the Tuning Indicator, turn the
knob to obtain optimum reception. The Op-
timum Tuning System (OTS) detects your
touch on the tuning dial and turns off the
circuit temporarily to allow precise tuning.
O REC CAL
This switch activates a test signal of 333 Hz
corresponding to 50% FM modulation that
can be used to accurately set recording levels -
before tape recording an FM broadcast. Be-
fore recording, turn the switch on and adjust
your tape deck for a level meter reading of
between —6 VU and 0 VU. The Rec Cal
switch should be left off when not in use.
O BLEND
When listening to a weak, noisy stereo
broadcast, this circuit can be used to reduce
nigh-frequency hiss at the expense of a slight
reduction in stereo separation. When the
switch is set to Auto, the received signal
level is automatically monitored, and if it is
weak the Blend circuit will be activated to
reduce hiss. in the Off position, the switch
provides best stereo separation.
OMUTE/OTS
This switch has three functions: FM muting,
OTS, and multipath detection. The switch
should normally be left on. The FM muting
circuit turns off the sound completely when a
strong station is not being received, thereby
eliminating interstation noise. In order to
receive a very weak station it is necessary to
turn the switch to the Off/Multipath position
to defeat the muting function.
The Optimum Tuning System is a Yamaha
exclusive feature which provides exceptional-
ly accurate tuning. An automatic circuit
detects any mistuning and actually readjusts
the tuned frequency to correct the problem.
OTS detects your touch on the tuning dial
and temporarily unlocks to allow manual tun-
Ing, then locks your station in perfectly when
you release the dial. When tuning in a weak
station adjacent to a strong one, the stronger
station may tend to pull OTS away from the
desired station. In this case, set the Mute/
OTS switch to Off/ Multipath to disable the
OTS circuit.
The T-7 incorporates a Signal Quality In-
dicator which detects the presence of multi-
path interference (see page 7). The Mute/
OTS switch must be set to the Off/Multipath
position for this function. и
RX MODE
The RX Mode (reception mode) switch lets
you adjust the T-7's IF stages for best results
on either strong or very weak stations.
In the Auto DX position the received signal
strength is monitored continously, and if it
falls below a certain level a high-gain, high-
selectivity circuit is switched in which pro-
vides the best possible reception of weak,
noisy stations. On stronger signals this circuit
IS automatically deactivated, for improved
distortion and stereo separation. On AM
broadcasts this switching is not automatic;
switch manually from DX to Local.
In the Local position the T-7 is set up to pro-
vide best results with strong, local stations.
Accurate music reproduction with low distor-
tion and good stereo separation will be
achieved.
O FUNCTION
This switch selects elther FM or AM broad-
casts. An indicator lights green when FM is
selected and red when the T-7 is switched to
AM.
® OUTPUT VARIABLE
This control on the bottom panel allows you
to adjust the “Variable” terminal output level
over the range of 0.1—1 V (measured at FM
100% modulation). The center click stop cor-
responds to a level of 500 mV.
® DX |
This indicator lights to show that the T-7 is
in DX mode.
® LOCAL
When the RX Mode switch (®) is in the
Local position or when the received station is
sufficiently strong, the indicator lights up to
denote Local mode. |
® STEREO
When an FM stereo broadcast is being
received this indicator automatically lights.
O SIGNAL QUALITY |
When tuning in a station, adjust the tuning
knob until the indicator lights up as far to
the right as possible. Refer to page 7 for a
detailed description.
RX MODE/
Ideally, a tuner should provide the best possi-
ble reception under all listening conditions. In
practice, however, this is difficult to achieve.
When receiving a weak, noisy station, it is
desirable for the tuner to have high selectivi-
ty, as this allows it to reject outside inter-
ference and provide clear reception. When a
strong station Is received, it is better for the
tuner to have low selectivity, because this
provides more accurate, distortion-free music
reproduction and increases stereo separation.
Conventional tuners have a constant selec-
tivity value which is a compromise, providing
reception that is adequate under most signal
conditions but is less than ideal. The T-7
solves this problem with its dual-selectivity IF
amplifier. With the RX Mode switch, you can
optimize the tuner for either weak or strong
stations, providing the best possible perform-
ance either way. See page 6 for an explana-
tion of how to use the switch. _
RX MODE
AUTO Dx
LOCAL
When receiving AM broadcasts, DX or Local
mode rmust be manually selected.
Fig. 3
SIGNAL QUALITY INDICATOR/
MULTIPATH INTERFERENCE:
This dual purpose indicator shows the signal
strength of the received station and also can
be used 10 detect multipath interference.
When the Mute/OTS switch is on the in-
dicator works as a signal strength meter and
Indicates the approximate antenna input.
When the Mute/OTS switch is at the
Off/Multipath position the multipath in-
terference detection circuit is engaged. The
signal strength indication is dimmed, and if
there is multipath interference the left-hand
portion of the indicator will light up as shown
in fig. 4. In order to get the best possible
reception, it is desirable to eliminate any
multipath interference either by rotating the
antenna or by replacing the antenna with one
that is more directional.
SIGNAL QUALITY
Multipath section
(example)
“Signal strength sectron
(example)
Fig. 4
Multipath is an effect similar to television
ghosting; it distorts the received signal and
also causes poor stereo separation and noise.
As shown in fig. 5, radio waves which travel
directly from the transmitter to the receiving
antenna are mixed with waves which reflect
off nearby objects such as buildings. Because
the path taken by the reflected waves is
longer than the direct path, the time required
for the waves to arrive at the antenna is also
longer. The mixing of the directly received
signal and the delayed signal noticeably
degrades reception quality. Multipath inter-
ference can be greatly reduced by the use of
a high-quality directional antenna oriented in
the proper direction. To assist you in di-
agnosing antenna problems, Yamaha pro-
vides a Signal Quality Meter (see previous
section) for detecting multipath interference.
_ Transmission antenna
Reflected
radio waves
Directly received
radio waves
FM receiving
antenna
Fig. 5
=3 PRESET TUNING/
POWER SUPPLY
In addition to having a conventional tuning
knob for selecting stations, the T-7 has a
convenient preset tuning system which allows
you to tune in your favorite stations with the
touch of a button.
To preset a station into the memory, first
tune the station in manually. Check to see
that the station has been tuned accurately for
the best possible reception. While pressing
the Memory button, press one of the num-
bered preset tuning buttons. The tuner will
then memorize the station's frequency. Any
time the appropriate numbered button is
pressed, the station will automatically be
tuned in. After you have preset a station, it is
a good idea to manually change to another
frequency and then push the newly memo-
rized station's button again to see that it is
tuned in correctly. Up to 5 AM and 5 FM
stations can be preset—a total of 10. In
other words, each numbered button selects
one of two stations —one FM and one AM—
depending on which band has been selected
by the Function switch.
MEMORY BACKUP
Preset tuning buttons
vevoey В E =F] sf] af] si
FUNCTION
AM
FM |
Function Memory button Station select
switch buttons Fig. 6
To tune in a previousiy memorized station,
first make sure that the Function switch is
set for FM or AM as appropriate. The in-
dicator will light up green for FM and red for
AM. Then press the numbered button cor-
responding to the desired station. The tuning
indicator will automatically move to the cor-
rect frequency and the station will be tuned
in. The preset tuning button will light to in-
dicate automatic station selection. Turning
the manual tuning knob turns the light off,
and a new station can be tuned in manually.
There may be cases where static electricity or
electrical noise from fluorescent lamps or
television sets prevent successful preset tun-
ing. Set the tuner away from such sources of
interference. When the button pressed has
been preset to a very weak station or there is
no broadcast station at the memorized fre-
quency, the frequency tuned in may deviate
slightly from the memorized frequency.
IT after a station has been tuned in auto-
matically the unit Is subjected to excessive
vibration or if the tuning knob is turned with
an insulated object such as a pencil, it may
not be possible to tune the station in again
automatically. This can be easily corrected by
selecting another station first and then
pushing the button of the desired station.
To preset a station into the memory.
'rpaeregrrer ii dE panreprain y I I Но 1 i 1
103 101 102 133 104
año sobn 1 doo dA duo
PURE Nd EARLE had kt
LH
‘
kHz
sf] „0 >
Press the station selec
button while holding
the Memory button in. à
Fig. 8
a | E
«pus ti qerut puetequari pellngi
se ва 10
In order to remember the frequencies of
preset stations even when the unit is
switched off, the T-7 continues to draw a
small amount of power when off. In order to
protect the memory contents in the event of
a power failure a rechargeable battery is used.
The tuner should be plugged in whenever
possible to keep this memory backup battery
fully charged. If the tuner is normally turned
on and off with a switched AC outlet or with
a timer, the battery will not be charged, and
the preset memory will be erased about two
hours after the unit is turned off. When the
battery is fully charged (charging time about
3 days) the memory will be retained for
about 4 months. When the unit is first pur-
chased the battery will require charging time.
It can be charged by plugging in the power
cord to a wall outlet (the power switch does
not need to be on).
TROUBLESHOOTING:
Before assuming that your tuner is faulty, check the following troubleshooting list which details the corrective action you can take
yourself without having to call a service engineer. If you have any doubts or questions, get in touch with your nearest YAMAHA dealer.
- Crackling sounds from time to time
(especially in weak signal areas).
Ignition noise from vehicles.
The FM antenna should be put up as high as possi-
ble, away from the road, and a coaxial cable used.
Noise from thermostats and other electrical
equipment.
Attach a noise suppressor to the equipment causing
the noise.
Noisy reception of stereo broadcasts.
Stereo is especially susceptible to noise when the
received signal is weak.
Use a high-quality directional FM antenna.
Place the RX Mode switch in the Auto DX position.
Place the Blend switch in the Auto position.
The FM Stereo indicator flickers on and off
and reception is noisy.
Insufficient antenna input.
Use an antenna appropriate for the reception
conditions in your area. |
Not tuned correctly.
Tune again.
There is distortion and clear reception cannot
be obtained even with a good FM antenna.
There is multipath interference,
Adjust antenna placement to eliminate multipath in-
terference (see page 7).
= Sounds from the left side leak to the right. A certain amount of crosstalk is normal. If the effect is small, there is no trouble.
The Signal Quality Indicator lights up but The muting circuit has turned off the sound because Place the Mute/OTS switch in the Off/Multipath
there is no sound. the received station is very weak. position to disable muting.
The amplifier volume control is too low. Readjust.
The volume is very low. :
The Output Variable control on the bottom panel is Readjust (see page 6).
too low.
Not tuned correctly. Tune the station precisely.
Only one side of the tuning indicator P у
lights up. The preset station called out was not properly Repeat the preset procedure.
memorized.
The memory has been erased because the tuner was
not plugged in for an extended time. Repeat the preset procedure,
Automatic station selection does not work. | —
You are touching the tuning knob while pressing the Do not touch the tuning knob when automatically
preset tuning button. tuning a preset station. |
. . . h
The received station is weak and noisy. The signal is too weak. Change the direction of the AM loop antenna.
Use an outdoor antenna. |
x . . These noises result from lightning, fluorescent Use an outdoor antenna and a ground wi Thi i]
There are continuous crackling and hissin hha and a ground wire. This wi
= | noises ° 9 9 lamps, motors, thermostats and other electrical help somewhat but it is difficult to eliminate all
< - equipment. noise.
There are buzzing and whining noises
{especially during the evening).
Another station is interfering with the received
station.
This is impossible to remedy.
A television set is being used nearby.
| Move the television a distance away.
SPECIFICATIONS
FM SECTION
10 Hz to 18 kHz
+ 0.5, — 3.0 аВ
Tuning Range
87.6 to 108 MHz
Subcarrier Product Ratio
70 dB
50 dB Quieting Sensitivity
Muting Threshold (DX)
5 uV (19.2 dBf)
Mono (DX)
3.2 pV (15.3 dBf)
Auto-DX Threshold
50 «V (39.2 dBf)
Stereo (DX, Blend on)
20 4 V (31.2 dBf)
(DX, Blend off)
38 uV (36.8 dBf)
AM SECTION
Usable Sensitivity
Tuning Range
525 to 1,605 kHz
IHF Mono (98 MHz, 40 kHz dev.)
1.7 uV (300 ohms) 9.8 dBf
Usable Sensitivity (IHF)
15 pV
0.85 uV (75 ohms) 9.8 dBf
Alternate Channel Selectivity
DIN Mono (40 kHz dev., S/N 26 dB)
1.2 uV
1,000 kHz +10 kHz
Local 17 dB, DX 27 dB
Signal-to-Noise Ratio 52 dB
image Response Ratio 50 dB (1,000 kHz)
Spurious Response Ratio 50 dB
Distortion 0.3%
AUDIO SECTION
Output Level/Impedance
FM (100% mod. 1 kHz)
1 V/600 ohms (Fixed)
500 mV/3.3 k-ohms (Variable center)
1 V/600 ohms (Variable max.)
AM (30% mod. 1 kHz)
300 mV/600 ohms (Fixed)
150 mV/3.3 k-ohms (Variable center)
300 mV/600 ohms (Variable max.)
Rec Cal Signal (333 Hz:
300 mY/600 ohms (Fixed)
Corresponding to 50%
250 mY/3.3 k-ohms (Variable center)
FM modutation)
GENERAL
Semiconductors
86 Transistors, 20 ICs, 4 FETS,
38 Diodes, 3 Zener Diodes, 14 LEDs.
Power Supply
Stereo (40 kHz dev., S/N 46 dB) 35uV
Image Response Ratio (98 MHz) 100 dB
IF Response Ratio (98 MHz) 100 dB
Spurious Response Ratio (98 MHz) 100 dB
AM Suppression Ratio (IHF) 67 dB
Capture Ratio (IHF) 1.5 dB
Alternate Channel Selectivity IHF Local 55 dB, DX 90 dB
DIN Local 30 dB, DX 70 dB
Signal-to-Noise Ratio (at 85 dBf)
Mono 90 dB
Stereo 85 dB
DIN (40 kHz dev.) Mono 84 dB
Stereo 79 dB
Distortion
Mono 100 Hz Local 0.03%, DX 0.1%
1 kHz Local 0.04%, DX 0.3%
6 kHz Local 0.07%, DX 0.7%
10 kHz Local 0.05%, DX 0.1%
Stereo 100 Hz Local 0.04%, DX 0.5%
1 kHz Local 0.04%, DX 0.5%
6 kHz Local 0.07%, DX 0.8%
10 kHz Local 0.08%, DX 1.5%
15 kHz Local 0.2%, DX 3.0%
intermodulation Distortion (IHF)
U.S. 8 Canadian Models
Power Consumption
120 Y, 60 Hz
U.S. & Canadian Models
Mono Local 0.04%, DX 0.5%
Stereo Local 0.04%, DX 1.0%
Stereo Separation
DC to 1 kHz Local 60 dB, DX 30 dB
2 kHz to 10 kHz
Local 52 dB, DX 25 dB
Frequency Response
14 W
Dimensions (Wx HxD)
435 x 95 x 335 MM
50 Hz to 10 kHz
+0.3 dB
(17-1/3” x 3-3/4” x 13-1/8”)
20 Hz to 15 kHz
+ 0.3, — 0.5 dB
Weight
5.2 kg (11 Ibs. 7 oz)
Specifications subject to change without notice
10
1-7 AM/FM STATION MEMORY CARD
FM 1 2 3 | 4 5
MHZ
STATION
AM 1 2 3 4 5
KHz
STATION
DATE € YAMAHA
1-7 AM/FM STATION MEMORY CARD
FM 1 o 3 4 5
MHz
STATION
AM 1 2 3 a 5
KHz
STATION
DATE a © YAMAHA
This card has been provided for your convenience in recording the names
“and frequencies of stations that have been preset into the T-7's
programmable memory. Refer to page 8 for preset procedure.
1-7 AM/FM STATION MEMORY CARD
FM 1 2 3 4 5
MHz
STATION
AM 1 2 3 4 5
KHz
STATION
DATE €3 YAMAHA
T-7 AM/FM STATION MEMORY CARD
EM 1 2 3 a 5
MHZ
STATION
AM 1 2 3 4 5
KHz
STATION
DATE — ES YAMAHA
… @ YAMAHA
NIPPON GAKKI CO., LTD. HAMAMATSU, JAPAN
Printed in Japan 8C
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement