B&K Precision 3011A User Manual

=>
INSTRUCTION
MANUAL
St > BK PRECISION
MODEL 3011A
2 MHz
DIGITAL DISPLAY
FUNCTION
GENERATOR
> ex Precision
TEST INSTRUMENT SAFETY
WARNING }
Normal use of test equipment exposes you to a certain amount of danger from electrical shock because testing must be per-
formed where exposed voltage is present. An electrical shock causing 10 milliamps of current to pass through the heart will stop
most human heartbeats. Voltage as low as 35 volts dc or ac rms should be considered dangerous and hazardous since it can pro-
duce a lethal current under certain conditions. Higher voltages pose an even greater threat because such voltage can more easily
produce a lethal current. Your normal work habits should include all accepted practices that will prevent contact with exposed
high voltage, and that will steer current away from your heart in case of accidental contact witha high voltage. You will signif-
icantly reduce the risk factor if you know and observe the following safety precautions:
1.
2.
Don't expose high voltage needlessly. Remove housings and covers only when necessary. Turn off equipment while making
test connections in high-voltage circuits. Discharge high-voltage capacitors after removing power.
If possible, familarize yourself with the equipment being tested and the location of its high voltage points. However, re-
member that high voltage may appear at unexpected points in defective equipment. | |
Use an insulated floor material or a large, insulated floor mat to stand on, and an insulated work surface on which to place
equipment; and make certain such surfaces are not damp or wet.
Use the time-proven "one hand in the pocket" technique while handling an instrument probe. Be particularly careful to
avoid contacting a nearby metal object that could provide a good ground return path.
When testing ac powered equipment, remember that ac line voltage is usually present on some power input circuits such as
the on-off switch, fuses, power transformer, etc. any time the equipment is connected to an ac outlet, even if the
equipment is turned off. ©
Some equipment with a two-wire ac power cord, including some with polarized power plugs, is the "hot chassis" type. This
includes most recent television receivers and audio equipment. A plastic or wooded cabinet insulates the chassis to protect
(continued on inside rear cover)
TABLE OF CONTENTS
TEST INSTRUMENT SAFETY ... 02... ccc ec nee ee tee eee wer ee nee teens Inside Front Cover
SPECIFICATIONS....,....... ce ee ee eee ee ee ete ee eee te eee eee eet eee ee eee eee tees 1
CONTROLS AND INDICATORS... 0... ce we one eee cere tee ee ee eee eee rennen ne 3
OUTPUT PROTECTION CONSIDERATIONS ......... ccc cece cece ence ee rer nn 5
OPERATING INSTRUCTIONS ........... еее оао nara ooo oa. ee ee eee ees 6
Frequency And Waveform Selection... oc ccc ccc ee ete eee tee ee een 6
DC Output. oo ss ce www ren 7
Voltage Controlled Fre-
quency OperatioN......o.oooooooooooo ee ee ttt ee te ee eee eee ee eens re 8
TTL/CMOS Output ....,...........,. nn 9
Duty Cycle Control „.... o ee wee ee eee een 9
MAINTENANCE... ccc ce ee ee een 11
Disassembly And Reassembly ....ooooooooooooo nooo een 11
Line Voltage Selection ....oooooooononoorororrrrrronaran.. anno ss soso 12
Fuse Replacement ....oooooo nooo ooo orar narran. oo... ooo ono... 12
WARRANTY SERVICE INSTRUCTIONS ............ еее еее ово вос во нев nono... 13
LIMITED ONE YEAR WARRANTY ........ еее error en 14
SPECIFICATIONS
Basic Outputs:
Frequency Range:
Maximum Amplitude:
Amplitude Control:
Attenuator:
Output Impedance:
DC Offset:
Duty Cycle Control:
Sine Wave Function:
Distortion:
(All specifications apply with frequency dial between 0.2 and 2 times range),
Sine Wave, Triangle Wave, Square
Wave, TTL Puise, and CMOS Pulse.
0.2 Hz to 2 MHz (7 ranges). Four
digit frequency counter display.
20 V p-p (open circuit).
10 V p-p (into 50 Я load).
Continuously variable, 20 dB range
typical.
-20 dB +1 dR.
50 2 16%.
Continuously variable, from -19 V
to +10 V (open circuit), -5 V to
+5 У into 500.
Continuously variable from 1:1 to
10:1,
0.2 Hz to 20 kHz; = 1%,
20 kHz to 200 kHz; <2%,
Frequency Response:
Square Wave Function:
Symmetry:
Rise Time:
Triangle Wave
Linearity:
TTL Output:
Level:
Rise Time:
CMOS Output:
Level:
Rise Time:
VCF (Voltage Controlled
Frequency) Input:
Input Voltage:
Impedance:
0.2 Hz to 100 kHz, <0.2 dB,
100 kHz to 2 MHz; <1 dB.
0.2 Hz to 100 kHz; = 2%.
< 120 ns.
0.2 Hz to 100 kHz; 98%,
100 kHz to 2 MHz; 95%.
> 3 Vp-p.
= 30 ns.
Continuously adjustable from
4 V p-p (#1 V p-p) to 14.5 V p-p
(40.5 У р-р).
= 120 ns.
Approximately +10 V (+1 V) causes
10:1 frequency change.
Approximately 10 kf.
SPECIFICATIONS
Frequency Counter
(Internal Only):
Accuracy:
Time Base Accuracy:
Power Source:
Weight:
+Time Base Accuracy +1 Count.
+10 PPM (23° C #59 C).
120/220/240 У AC 410%, 50/60 Hz.
5.5 lb (2.5 ke).
Dimensions (W x H x D):
Aecessories Supplied:
9.65 x 3.75 x 11",
245 x 95 x 280 mm.
One cable, BNC to insulated clips.
Power Cord.
Spare Fuse.
Instruction Manual.
schematic Diagram & Parts List.
CONTROLS AND INDICATORS
1 2 3
\ \ ==
> ax precisos 3011A “== [E iM к 10K 1K IT N ru
7 PA
i w/sfs[s/afsjejs, OOO
/ 108 ——FUNCTION——~
13 = on DUTY OFFSET PUSH TTL AMPL
Mor PULL INV PULL ADJ PULL CMOS PULL-20dB
ADJ
О OT
12- tes CAL SV 15V у МАХ
S TTL/CMOS OUTPUT
DS 2MHz
FUNCTION GENERATOR
\ \ \ \ \
Y Ÿ Y N Ÿ
11 8 7 6 5
Fig. 1. Controls And Indicators
3
CONTROLS AND INDICATORS
1.
2.
PWR Switch. Turns power оп and off.
Range Selectors. Selects frequency range. Decade fre-
quency type, seven ranges from 1 Hz to 1 MHz. Fre-
quency can be adjusted from 0.2 to 2 times the range
selected. For example, if the 100 K range is selected,
frequency can be adjusted (see Frequency Control) from
20 kHz to 200 kHz. Numbers under pushbuttons indicate
gate time (see GATE LED),
Function Selectors. Selects square, triangle, or sine
waveform at OUTPUT jack.
AMPL/PULL -20 dB Control.
signal at OUTPUT jack.
signal is attenuated 20 dB.
Controls amplitude of
When control is pulled out,
OUTPUT Jack. Waveform selected by FUNCTION
Switches as well as the superimposed DC OFFSET
voltage is available at this jack.
PUSH TTL/PULL CMOS. When control is pushed in, a
TTL signal is present at the TTL/CMOS jack. Level is
fixed at 3 V p-p and turning control has no effect. When
the control is pulled out, a CMOS signal is present at
the TTL/CMOS jack. Turning the control clockwise
increases the amplitude and turning the control coun-
terclockwise decreases amplitude (amplitude is adjust-
able from approximately 4 V p-p to 14.5 V p-p).
TTL/CMOS Jack. Square wave selected by PUSH TTL/
PULL CMOS control (either TTL or CMOS) is available
at this jack. The output is independent of the AMPL/
PULL -20 dB and OFFSET/PULL ADJ controls.
10.
11.
12.
13,
OFFSET/PULL ADJ Control. When control is pushed in,
DC offset is set at zero. When control is pulled out,
clockwise rotation changes DC offset in a positive di-
rection and counterclockwise rotation changes DC off-
set is a negative direction, Full clockwise rotation
gives approximately +5 V into 50 2 load (+10 V open cir-
cuited). Full counterclockwise rotation gives approxi-
mately -5 У into 50 Я load (-10 У open circuit).
VCF IN Jack. Voltage Controlled Frequency input.
Permits external sweep or frequency control. Positive
voltage decreases the output frequency.
DUTY/PULL INV Control. Adjusts the duty cycle of
both the main OUTPUT signal and the TTL/CMOS sig-
nal. When control is pulled out, the square wave at the
main OUTPUT and the TTL or CMOS signal are in-
verted. Fully counterclockwise rotation is the CAL
position (normal duty cycle). Duty cycle changes when
control is rotated away from CAL position.
Frequency Control. This control adjusts the frequency
of the main output (square, triangle, or sine wave) and
the TTL/CMOS output from approximately 0.2 to 2
times the selected range. The last major line in the
counterclockwise position is the 0.2 position and the last
major line in the clockwise position is the 2 position,
Frequency Counter Display.
internally generated frequency.
Displays frequency of
Hz and kHz LED,
Hz or kHz.
Indicates whether display is showing
CONTROLS AND INDICATORS
14. GATE LED. Indicates when frequency counter display is
updated. When the 10 K through 1 M frequency
switches are selected, the LED will flash 10 times per
second (every 0.1 second). When the 10 through 1 K
switches are selected, the LED will flash once each
second and when the 1 switch is selected, the LED will
light every 10 seconds. As the LED turns off, the dis-
play is updated,
OUTPUT PROTECTION CONSIDERATIONS
Use care when connecting any funetion generator output to
a signal injection point. Excessive voltage at the point of
signal injection can be reflected into the function generator
circuitry causing internal damage. The TTL output is
particularly susceptible to damage from externally applied
voltage greater than +6 volts or any negative polarity
voltage.
Damage of this type usually oceurs by accidentally
connecting the output of the function generator across a
voltage in the equipment under test. To be completely safe,
adherence to the following protective measures is strongly
recommended:
1. The user should understand the equipment under test
well enough to identify valid signal injection points (ie;
the base of a transistor, a logic input of a gate, etc.).
The voltage across valid signal injection points rarely is
high enough to damage the instrument.
2. If in doubt about the safety of a signal injection point,
measure the in-circuit voltage present at the point of
signal injection before connecting a function generator
output to the circuit, ascertaining whether it is safe to
connect the generator to the circuit.
When using the main output of the function generator
and connection across a circuit point containing a de
level is unavoidable, adjust the DC OFFSET control on
the generator to match the existing circuit voltage.
Conneet the TTL OUTPUT only to TTL-level circuits.
Connect the CMOS OUTPUT only to CMOS circuits
(Model 3011A). Measure the Vee of the circuit under
test and adjust the CMOS ADJust as instructed in the
manual.
When function generator is used by students or other
inexperienced users, the following circuit could be
added into your TTL output probe or test clip set. It
will protect the TTL output of the generator against
external voltages up to +20 volts.
150 ©, 2 W
TTL (+) >
FUNCTION GENERATOR 5.6 ler 0 TO
TTL OUTPUT 1W CIRCUIT
GROUND >
Circuit for Protection of TTL Output.
OPERATING INSTRUCTIONS
FREQUENCY AND WAVEFORM SELECTION
1.
With the unit plugged into a power source, depress the
PWR switch.
Select the desired frequency range by depressing the
appropriate range switch. The output frequency is dis-
played, with the appropriate decimal point, on the LED
display. The Hz or kHz indicator is also lit. Turning the
frequency dial will vary the output frequeney from
approximately two-tenths the indicated range value (se-
lected with the range switches) to two times the value.
For example, if the 10 K range is selected, when the
frequency dial is set to the counterclockwise most
major line, the output frequency will be approximately
2 kHz. When the frequency dial is set to the clockwise
most major line, the output frequency will be approxi-
mately 20 kHz. Fig. 3 shows these major lines. The
frequency selected is available at both the TTL/CMOS
Jack and the OUTPUT jack.
NOTE
A. It is best not to set the frequency dial beyond
either the 0.2 or 2 (times frequency range)
position. Instead, select the next lower or
higher range. When the frequency dial is set
to such a position, erratic operation could
occur.
B. When the 1 Hz range is selected, the gate
time is 10 seconds. This means that the
display is only updated once every 10
seconds. Because of this long gate time, the
frequency dial must be adjusted very
slowly. Each time that the display is
updated, the dial can be adjusted a little bit
further toward the desired value.
Recommended
Range
NN) | UD
Fig. 3. Frequency Dial.
Select the waveform desired (square, triangle, or sine)
by depressing the appropriate FUNCTION switch. The
phase relationships of the waveforms available are
shown in Fig. 4. Be sure that the DUTY control is set to
CAL.
$e nn
OPERATING INSTRUCTIONS
The amplitude of the selected output signal at the main
OUTPUT jack is adjusted with the AMPL/PULL -20 dB
control. Maximum signal level is 10 V p-p (into 50 9),
and signal level can be decreased by turning control
counterclockwise, or pulling the control out for an addi-
tional 20 dB step of attenuation.
For information on the TTL and CMOS signals, see the
"TTL/CMOS OUTPUT" section of this manual.
A DC component can be added to the signal at the main
OUTPUT jack by use of the OFFSET/PULL ADJ con-
trol. The DC component introduced is independent of
the AMPL/PULL -20 dB control and does not apply to
the TTL/CMOS jack. The level of DC can be varied by
+10 volts open circuited or +5 volts into 50 Я.
NOTE
Remember that the output signal swing of the
generator is limited to +10 volts open circuited or
+5 volts into 50 2. This applies to the combined
signal and DC offset. Clipping oceurs slightly
above these levels. Fig. 5 illustrates the various
operating conditions encountered when using the
DC offset. If the desired output signal is large or
if a large DC offset is required, an oscilloscope
should be used to make sure that the desired com-
bination is obtained without undesirable clipping.
When using the higher output frequencies and when
using the square wave output, terminate the cable
into 50 Я to minimize ringing. Also, keep cables as
short as possible,
INV SQUARE
OV
INV CMOS I
OV
INV TTL |
|
dla
ov Adjust w/ —
duty cont.
Adjust w/
frequency cont.
Note that TTL is opposite polarity
of square wave (main output)
and CMOS is opposite polarity
of TTL.
tb
Fig. 4. Output Waveform And Phase Relationship.
DC OUTPUT
The DC OFFSET feature allows this Function Generator to
be used as a bipolar DC power supply with an internal
impedance of about 50 9.
OPERATING INSTRUCTIONS
A. Zero DC offset
with maximum
signal
. Offset limits
without clipping
o 5
|
|
|
|
NN
| |
|
ШИ
> |
Г |
=
|
Pasitive Negative
DC offset DC offset
+51 м
С. Excessive offset Ov AN —— AN
u Positive u ne Negative
DC offset DC offset
Fig. 5. Use of DC OFFSET Control.
1. Depress the FUNCTION switches slightly so that all the
switehes are released (all buttons out) and turn the
AMPL/PULL -20 dB control fully counterclockwise (to
MIN). This removes the signal component from the
output.
NOTE
Do not pull the AMPL/PULL -20 dB control out.
This will attenuate the DC OFFSET by 20 dB.
2. The output now consists of a DC voltage which can be
varied continuously from -10 volts to +10 volts (open
circuit) by use of the DC OFFSET control.
VOLTAGE CONTROLLED FREQUENCY OPERATION
The Model 3011A can be operated as a voltage-controlled
oscillator (VCO) by using an external control voltage applied
to the VCF IN jack. The externally applied voltage will vary
the frequency which is preselected by the range switches and
the frequency control dial. Applying approximately +10 V
will eause the frequency to decrease by about 10 times (a
10:1 ratio).
CAUTION
Do not apply more than +15 volts (de or de + ac
peak) to the VCF IN jack. Inputs of more than
15 volts will not cause any further shift in the fre-
queney and could cause damage to aceur to the
Funetion Generator.
1. Select the desired frequency range and function.
bo
.
Set the DC offset, if required.
3. Set the starting frequency and amplitude to the desired
level.
NOTE
Keep the (starting) frequency control dial between
the 0.2 and 2 positions (see Fig. 3).
4. То operate the function generator as a sweep generator,
apply a positive going ramp signal to the VCF IN jack.
OPERATING INSTRUCTIONS
As the voltage increases, the frequency decreases. A
ramp that goes from 0 to +10 V will cause the frequency
to decrease by a factor of 10 (i.e., if the starting fre-
quency is 10 kHz, when the ramp reaches +10 V, the
output frequency will be 1 kHz). The rate of sweep can
be adjusted by varying the frequency of the ramp signal.
5. Specific frequencies can be selected by applying a fixed
de voltage to the VCF IN jack or the frequencies can be
stepped by applying a stepped de voltage.
TTL/CMOS OUTPUT
The TTL/CMOS output jack provides a fast rise time
square wave output (no triangle or sine output available).
Either a fixed 3 V p-p TTL or a variable (approximately
4 V p-p to 14.5 V p-p) CMOS output are available. The output
pulses always go positive with respect to ground. This signal
can be used as an external sync pulse for oscillscopes or as a
variable frequency signal source for exercising logic circuits.
NOTE
Because of the fast rise time of this output, cable
length should be minimized to limit ringing and
overshoot,
1. Select the desired frequency range and adjust the fre-
quency dial as required. The AMPL/PULL -20 dB and
OFFSET/PULL ADJ control have no effect on the signal
at the TTL/CMOS jack.
2. Select a TTL signal by pushing in the PUSH TTL/PULL
CMOS control, Select a CMOS signal by pulling out the
PUSH TTL/PULL CMOS control and adjust the level of
the CMOS signal by rotating the control (the TTL level
is fixed).
DUTY CYCLE CONTROL
The Model 3011A Function Generator has a variable duty
eyele control to provide ramps (sawtooth) or pulses. The duty
cycle control effects both the main OUTPUT and the TTL/
CMOS output. If a standard square, triangle, or sine
waveform are desired (normal duty cycle) the DUTY control
should be set to CAL (fully counterclockwise). Fig. 5
illustrates the funetion of the DUTY/PULL INV control.
NOTE
As the DUTY cycle is changed, the frequency will
decrease. Be sure to set the desired frequency
after the DUTY cycle has been adjusted.
1. Select the desired function (either square or triangle
wave if the main OUTPUT is to be used or TTL or
CMOS if the TTL/CMOS output is to be used) and
frequency range.
2. Adjust the amplitude and DC offset if the main
OUTPUT is to be used or adjust the CMOS level if a
CMOS signal is to be used (the TTL has a fixed level).
3. Adjust the DUTY/PULL INV control so that the desired
duty cycle is obtained (display on oscilloscope for set-up
if desired).
4. Adjust the frequency of the signal using the frequency
control dial. The DUTY/PULL INV control can be
OPERATING INSTRUCTIONS
pulled out to cause a negative going pulse at either the CMOS jack (the triangle and sine wave cannot be in-
main OUTPUT jack (for square wave only) or the TTL/ verted).
SQUARE
0
CMOS
м — L |
m Mm Mm
INV SQUARE
OV
INV CMOS >]
Ov
Г. LJ LJ LJ
Adjust w/ | | o |
duty cont. Note that TTL is opposite polarity
| of square wave (main output)
— Adjust wi and CMOS is opposite polarity
frequency cont. of TIL.
|
Fig. 6. Effect Of DUTY/PULL INV Control On Square Wave, TTL, And CMOS Signal.
10
MAINTENANCE
WARNING }
The following instructions are for use by qual-
ified service personnel only. To avoid electrical
shock, do not perform servicing other than con-
tained in the operating instructions unless you
are qualified to do so.
Remember that ac line voltage is present on line
voltage input circuits any time the instrument is
plugged into an ac outlet, even if turned off.
Always unplug the Function Generator before
performing service procedures.
DISASSEMBLY AND REASSEMBLY
In order to aecess the fuse and the line voltage selector,
the bottom half of the case must be removed. To remove the
bottom of the case:
Disassembly
1. Unplug the Function Generator and turn the unit upside
down. Remove the four screws and the rubber foot pads .
from the bottom of the unit.
2. Lift the bottom section of the case up.
Reassembly
1. Line up the slots in the bottom case half with the front
panel and put the two case halves together.
2. Replace the rubber foot pads and screws.
Line
220) rt Voltage
Selector
Fig. 7. Fuse And Line Voltage Selector Location.
11
MAINTENANCE
LINE VOLTAGE SELECTION
1. If the line voltage needs to be changed, disassemble the
function generator case (see the DISASSEMBLY section
above) and unplug the plastic connector by pulling it
straight up (see Fig. 7 for location).
с. Align the plastic connector with the desired voltage se-
lector pin and push the plug down over the pin. Be sure
that the correct fuse is installed (0.5 A for 110 V opera-
tion and 0.3 A for 220 or 240 V operation) in the fuse
holder. Reassemble the case.
FUSE REPLACEMENT
l. To replace the fuse, disassemble the case and remove
the blown fuse (see Fig. 7 for location).
12
2. The fuse should not normally open unless a problem has
developed with the unit. Try to determine and correct
the cause of the blown fuse, then replace only with the
correct value fuse (0,5 A for 110 V operation and 0,3 A
for 220 or 240 V operation). Reassemble the case.
INSTRUMENT REPAIR SERVICE
Because of the specialized skills and test equipment re-
quired for instrument repair and calibration, many customers
prefer to rely upon B & K-Precision for this service. We
maintain a network of B & K-Precision authorized service
agencies for this purpose. To use this service, even if the in-
strument is no longer under warranty, follow the instructions
glven in the WARRANTY SERVICE INSTRUCTIONS portion
of this manual. There is a nominal charge for instruments out
of warranty.
WARRANTY SERVICE INSTRUCTIONS
(For U.S.A. and its Overseas Territories)
To send in your unit, pack it securely (preferably in the original
carton or double-packed). Enclose a letter describing the problem
and inelude your name and address. Deliver to, or ship PREPAID
(UPS preferred in U.S.A.) to the nearest B & K-Precision author-
ized service agency (see list enclosed with unit).
If your list of authorized B & K-Precision service agencies has
been misplaced, contact your distributor for the name of your
nearest service agency, or write to:
B & K-Precision, Factory Service Department
Maxtec International Corporation
6470 West Cortland Street
Chicago, Illinois 60635
Tel (312) 889-1448
Also use this address for technical inquiries
and replacement parts orders.
13
TEST INSTRUMENT SAFETY
(continued from inside front cover)
the customer. When the cabinet is removed for servicing, a serious shock hazard exists if the chassis is touched. Not only
does this present a dangerous shock hazard, but damage to test instruments or the equipment under test may result from
connecting the ground lead of most test instruments to a "hot chassis". To test "hot chassis" equipment, always connect an
isolation transformer between the ac outlet and the equipment under test. The B & K-Precision Model TR-110 or 1604 Iso-
lation Transformer, or Model 1653 or 1655 AC Power Supply are suitable for most applications. To be on the safe side,
treat all two-wire ac powered equipment as “hot chassis" unless you are sure it has an isolated chassis or an earth ground
chassis.
On test instruments or any equipment with a 3-wire ac power plug, use only a 3-wire outlet. This is a safety feature to
keep the housing or other exposed elements at earth ground.
Never work alone. Someone should always be nearby to render aid if necessary. Training in CPR (cardio-pulmonary resus-
citation) first aid is highly recommended.