B&K Precision 4040A User Manual

INSTRUCTION

MANUAL

MANUAL DE INSTRUCCIÓN

Model 4040A

MODELO 4040A

20 MHz SWEEP/FUNCTION

GENERATOR

with FREQUENCY COUNTER

20 MHz GENERADOR DE

BARRIDO/FUNCIONES CON

CONTADOR DE FRECUENCIA

2

TEST INSTRUMENT SAFETY

WARNING

Normal use of test equipment exposes you to a certain amount of danger from electrical shock because testing must sometimes be
performed where exposed voltage is present. An electrical shock causing 10 milliamps of current to pass through the heart wil l stop
most human heartbeats. Voltage as low as 35 volts dc or ac rms should be considered dangerous and hazardous since it can produce a
lethal current under certain conditions. Higher voltages pose an even greater threat because such voltage can more easily pro duce a
lethal current. Your normal work habits should include all accepted practices to prevent contact with exposed high voltage, and to
steer current away from your heart in case of accidental contact with a high voltage. You will significantly reduce the risk factor if you
know and observe the following safety precautions:

1. 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.

2. If possible, familiarize yourself with the equipment being tested and the location of its high voltage points. However, remem ber

that high voltage may appear at unexpected points in defective equipment.

3. 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.

4. 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.

5. 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.

(continued on inside back cover)

3

Instruction Manual

for Model 4040A

20 MHz

SWEEP/FUNCTION GENERATOR

with FREQUENCY COUNTER

22820 Savi Ranch Parkway • Yorba Linda, CA 92887

4

TEST INSTRUMENT SAFETY .......... inside front cover

INTRODUCTION ....................................................... 5

SPECIFICATIONS ..................................................... 6

CONTROLS AND INDICATORS ............................... 8

OPERATING INSTRUCTIONS ................................ 11

Frequency and Waveform Selection . ......................... .11

Duty Cycle Control .................................................. 13

Burst Operation ........................................................ 14

AM Operation .......................................................... 15

FM Operation . .......................................................... 16

TTL/CMOS Output .................................................. 17

Voltage Controlled Frequency Operation ....................... 17

Sweep Operation .......................................................... 18

Use of Frequency Counter with External Signals ............ 18

Output Protection Considerations .................................. 19

Function Generator Applications Guidebook.................. 19

MAINTENANCE ........................................................ 20

Fuse Replacement ........................................................ 20

Instrument Repair Service ............................................ 20

Customer Support ......................................................... 21

WARRANTY SERVICE INSTRUCTIONS.................... 22

LIMITED TWO-YEAR WARRANTY ........................... 23

SPANISH MANUAL .................................................... 25

TABLE OF CONTENTS

5

INTRODUCTION

The B&K Precision Model 4040A Sweep/Function Generator

is a versatile signal source which combines several functions into
one unit - waveform generation, pulse generation (through variable
symmetry), and frequency sweep. Additionally, the instrument
provides the added convenience of a built-in frequency counter.
This permits more accurate determination of output frequency than
is possible with a simple calibrated dial. Coarse and fine tuning
controls permit precision stability of the output frequency. The
internal frequency counter can also be used to measure external
frequencies.

The five-digit frequency counter displays the generator output

frequency or external signals from 5 to 30MHz.

With this versatility, the unit has a vast number of applications
in both analog and digital electronics in the engineering,
manufacturing, servicing, educational, and hobbyist fields.

The heart of the function generator is a VCG (voltage-controlled
generator) that produces precision sine, square, or triangle waves
over the 0.2Hz to 20MHz range. This encompasses subaudible,
audio, ultrasonic, and RF applications. A continuously variable dc
offset allows the output to be injected directly into circuits at the
correct bias level.

The sweep generator offers linear or log sweep with variable
sweep rate and adjustable sweep time. Front panel controls allow
the start and stop frequencies to be set.

Burst operation enables the output to be gated by an internal,
adjustable signal or by an externally applied signal.

Variable symmetry of the output waveform converts the
instrument to a pulse generator capable of generating rectangular
waves or pulses, ramp or sawtooth waves, and slewed sine waves.

The output can be either amplitude modulated or frequency
modulated. Modulation can be by a 1 kHz internal, adjustable
signal or by an externally applied signal.

In addition to the above features, an external voltage may be
used to control operating frequency. This is useful in situations
where an externally controlled frequency is desirable.

Many functions can be operated simultaneously, making
possible such complex outputs such as gated pulse trains with
external or internal sweep.

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FREQUENCY CHARACTERISTICS

Waveforms: Sine, Square, Triangle, ± Pulse, ± Ramp
Range: 0.2Hz to 20MHZ in 8 ranges
Resolution: 5 digits

Tuning Range: Coarse: 10:1, Fine: ± 5% of Coarse

Setting

Variable Duty Cycle 15:85:15 Continuously Variable
Operating Modes Normal, Sweep, VCG, AM, FM, Burst
Frequency Stability: The output will change less than 0.09%

over 15 minutes after 1 hour warmup.

OUTPUT CHARACTERISTICS

Impedance: 50Ω ± 10%
Level: 20V p-p Open-circuit, 10V p-p into 50Ω

to 10MHz

Amplitude Control: Variable, 20dB range typical
Attenuation: -20dB ±1dB
Dc Offset: Preset: ±0.V typical
Variable: ±10V open-circuit, ±5V into 50Ω

Sine Wave

Distortion: 0.1Hz to 100KHz: ≤3%

Flatness: ±5% (0.45 dB) 10Hz to 8MHZ
±20 % ( 2.0 dB) 8MHZ to 20MHZ @
3Vp-p

Square Wave

Symmetry: ≤2% 0.2Hz to 100 kHz

Rise Time: ≤30ns (Typical)

Overshoot &

Undershoot ≤5%

TRIANGLE WAVE

Linearity: ≥98% to 100kHz

TTL OUTPUT

Level: 0.8V to 2.4V

Rise Time: ≤20 nS

Duty Cycle: 50% typical

CMOS OUTPUT

Max Frequency: 2MHz

Level: 4V to 14V ±0.5V p-p,

continuously variable

Rise Time: ≤120nS

VCG (Voltage Controlled Generator) INPUT

Input Voltage: 0-10V ± 1V causes a 100:1 frequency
change

Impedance: 10kΩ ±5%

SPECIFICATIONS

7

SPECIFICATIONS

SWEEP OPERATION

Mode: LIN / LOG
Width: 100:1, Continuously variable
Rate: 20mS to 2 sec, continuously
variable
Sweep Output: 0 to 2V
Start/Stop

Frequencies: Adjustable

AM MODULATION CHARACTERISTICS

Source: Internal, External

Modulation Ratio: 0 To 100%

INT. Modulation: 1kHz

EXT. Modulation: DC to 500KHz

EXT. Sensitivity: Less than 10V p-p for 100%
modulation

FM MODULATION CHARACTERISTICS

Source: Internal, External

Deviation: 0 to 5%

INT. Modulation: 1kHz

EXT. Modulation: DC to 500kHz

EXT. Sensitivity: Less than 10V p-p for 100%
modulation

BURST CHARACTERISTICS

Source: Internal, External
Burst Width: Continuously variable from 5%

to 90% of internal gating frequency

Repetition Rate: 0.5Hz to 50Hz, internal or DC to

500kHz, external

Burst Frequency: Determined by the main generator

frequency setting. Tone burst is in

integral cycles of frequency being

gated.

FREQUENCY COUNTER

Accuracy: Time Base Accuracy ±1
count
Time Base Accuracy: ±10PPM (23°C ±5°C)
Display: 5 digit LED
External Input:

Frequency: 5Hz to 30MHz
Resolution: 0.1, 1, 10, 100, 1 kHz
Sensitivity: ≤25 mV rms
Impedance: 1 MΩ/100 Pf

AC INPUT

120/230VAC ±10%, 50/60Hz, internal jumper selectable

DIMENSIONS (H x W x D)

10 1/2" x 5 1/2" x 12 3/8" ( 26.67cm x 13.97cm x 31.43cm )

WEIGHT

5.3 lb. (2.4 kg.)

ACCESSORIES

Output Cable, BNC to Alligator Clips
Instruction Manual

NOTE: See Maintenance section for AC Line Selection and fuse information. Specifications and information are subject to change without
notice. Please visit www.bkprecision.com for the most current product information.

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FRONT PANEL (Refer to Fig. 1)

1. POWER Switch. Turns power on and off.

2. DUTY CYCLE Switch. When engaged, enables

operation of DUTY CYCLE control (7).

3. CMOS LEVEL Switch. When engaged, changes the

TTL signal to CMOS signal at the TTL/CMOS
jack, and enables operation of CMOS LEVEL
Control (8).

4. DC OFFSET Switch. When engaged, enables

operation of the DC OFFSET control (11).

5. -20dB Switch. When engaged, the signal at the

OUTPUT jack is attenuated by 20dB.

6. RANGE Switch. Selects output frequency range.

Eight ranges from 2Hz to 20MHz. Switch indicates
maximum frequency of range and is adjusted with
COARSE FREQUENCY control to 0.1 times the
maximum. For example, if the 200 kHz range is
selected, the output frequency can be adjusted
from 20kHz to 200kHz.

7. DUTY CYCLE Control. Activated by the DUTY

CYCLE Switch (2). Rotation from center position
adjusts the duty cycle of the main OUTPUT signal
and TTL/CMOS signal.

8. CMOS LEVEL Control. Rotating this control

clockwise increases the amplitude of the CMOS
signal at the TTL/CMOS jack.

9. FUNCTION Switch. Selects sine, square, or triangle

waveform at OUTPUT jack.

10. OUTPUT LEVEL Control. Controls the amplitude of

the signal at the OUTPUT jack. Output level can be
decreased by approximately 20dB with this control.

11. DC OFFSET Control. Activated by the DC OFFSET

Switch (4). Clockwise rotation from center changes
the DC offset in a positive direction while
counterclockwise rotation from center changes the DC
offset in a negative direction.

12. VCG/MOD INPUT Jack. Controlled by

MODULATION OFF/ON Switch (33). When
MODULATION OFF is selected, jack is the Voltage
Controlled Generator input and permits external
control of generator output frequency by a DC voltage
input at this jack. A positive voltage will decrease
frequency. When MODULATION ON is selected, jack
becomes modulation input source.

13. OUTPUT Jack. Waveform selected by FUNCTION

Switch as well as the superimposed DC OFFSET
voltage is available at this jack.

14. BURST INPUT Jack. Input for external gating signal

for Burst operation.

15. TTL/CMOS Jack. TTL or CMOS square wave,

depending on the position of the CMOS LEVEL
switch (3) is output at this jack. This output is
independent of the OUTPUT LEVEL and DC OFFSET
controls.

16. EXT. COUNTER INPUT Jack. Input for external

frequency measurements.

CONTROLS AND INDICATORS