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Model 739A
SECTION I
DESCRIPTION
The @ Model 739A Frequency Response Test attenuator reduces the signal to an appropriate
Set simplifies frequency response determination output level which appears acfoss 50 ohms at the
by providing a convenient constant amplitude re- end of the special output cable supplied.
ference voltage of variable frequency. Frequency
response of vacuum tube voltmeters, oscilloscope,
video amplifiers and filters from 5 cps to 10 mc*
ATTEN.
can be quickly and easily checked.
.30-IO MC IOdb STEPS
The Frequency Response Test Set contains a wide
range oscillator, special voltmeter and step attenu- METER
SET 50 5
ator as shown in Figure 1. The osciilator generates
2
constant amplitude signals between 300 kc and 5
MONITOR 0
10 mc. The monitoring circuit is flat from 5 cps
to 10 mc so that an external oscillator suchas
@ Model 200s can be used to reduce the lower
En INPUT
frequency limit to as low as 5 cps. Oscillator
output is applied to the monitoring voltmeter, which RO
samples the input to a stepattenuator. An arbitrary
reference level is maintained on the monitoring
meter as the frequency setting is varied. The Figure 1. Model 739A Block Diagram
SPECIFICATIONS
FREQUENCYRANGE: 5 cycles* to 10 mc.
INTERNAL OSCILLATOR: 300 kc to 10 mc in 3 ranges.
REQUIREMENTS FOR Frequency range 5 CPS to 300 kc requires 3 volts into 50 ohms,
EXTERNAL OSCILLATOR: distortion less than 1%.
FREQUENCY RESPONSE OF Flat within 50.5% from 10 CPS to 5 mc; within+0.5%, -l.S%,
MONITORING CIRCUIT: 5 cps to 10 mc. Monitor circuit is average responding.
OUTPUT: At least 3 volts across 50 ohm cable termination. Adjustable
in 10 db steps by a Oto70 db attenuator. Fine adjustment pro-
vided.
DIMENSIONS: Rack Mount: 7 in. high, 19 in. wide, 9 in. deep.
ACCESSORIES FURNISHED 739A-16A Output Cable, 50 ohm termination. BNC to shielded
dual banana plug, (extra cables available on special order).
* Extended frequency range when used with @ Model 200s
Oscillator. |
ACEC
