Receiver AVC Characteristic Test

TM 1 1-5820-509-35

Test

Radio

equipment

control

Test

Performance

Step

settings

procedures

standards

Same as step 1 at each of the

Same as step 1 at the following

Repeat procedure of step

a. Same as step 1a at each operat-

following frequencies: 3226,

KILOCYCLES indicator read-

1a at each operating fre-

ing frequency.

3776, 4226, 4776, 5226, 5776,

dings: 3225, 3775, 4225, 4775,

quency.

6226, 6776,7226, 8226,

5225,5775, 6225, 6775, 7225,

b. Repeat procedure of step

b. Same as step 1b at each operat-

8776, 9226, 9776, 10226,

7775, 8225, 8775, 9225, 9775,

1b at each operating fre-

ing frequency.

10776, 11226. 11776 kHz;

10225,10775, 11225,and

quency.

maintain 2.0 microvolts output.

1175.

Same as step 1 .

Same as step 1 except use 26.5

a. Repeat procedure of step

a. Same as step 1a.

volt dc primary power source.

1a using 26.5-volt dc pri-

mary power source.

b. Repeat procedure of step

b. Same as step 1b

lb using 26.5-volt dc pri-

mary power source.

Same as step 2.

Same as step 2 except use 26. 5

a. Repeat procedure of step

a. Same as step 1a at each operating

volt dc primary power source.

1a at each operating fre-

frequency.

quency using 26.5-volt

dc primary power source.

b. Repeat procedure of step

b. Same as step 1b at each opera-

lb at each operating fre-

ting frequency.

quency using 26.5-volt

de primary power source.

(2) Connect the primary power source to the receiver-

4-7. Receiver AVC Characteristic Test

transmitter.

(fig; 4-1)

a. Test Equipment and Material.

(3) Turn on the test equipment and place the POWER-

(1) Signal Generator SG-103/URM-25F

LIGHTS switch of RT-671/PRC 47 to POWER ON.

(2) Frequency Counter AN/URM-79/U

Permit the equipment to stabilize for at least 5 minutes

(3) Spectrum Analyzer TS 723A/U.

before beginning the procedures shown in the chart

(4) Audio load, 300-ohm, 1-watt composition

below.

resistor.

(5) Primary power source: 115-volt, 400 Hz,

c. Procedure. After each adjustment of the frequency

single-phase, 3 amps.

26.5-volt, dc, 11 amperes

control knobs on the front panel of the receiver-

approx.

transmitter, readjust the signal generator output

frequency to the newly selected transmitter operating

b. Test Conditions and Equipment Connections.

frequency plus 1kHz, and reset the output level to the

(1) Connect the test equipment to Radio

required valve.

Receiver-Transmitter RT-671/PRC47 as shown in figure

4-1.

Test

Radio

equipment

control

Test

Performance

Step

settings

procedures

standards

Adjust signal generator to

Adjust frequency control knobs

Read audio output voltage

Record output voltage for

2226 kHz; set output level to

to 2225 on KILOCYCLES in-

across 300-ohm audio load.

reference below.

5.0 microvolts.

dicator; CW-FSK/VOICE to

VOICE; OPR-TUNE to OPR;

VOLUME control to maximum

clockwise stop.

Increase signal generator out-

Same as step 1.

Read audio output voltage

Reading in this step must not ex-

put to 0.1 volts.

across 300-ohm audio load.

ceed 3.16 times the reading in

step 1.

Same as 35 step 1 except set cut-

Same as step 1except set fre-

Repeat procedures of step 1 at

Record output voltage for

put to 4226 kHz.

quency control knobs for

4225 kHz.

reference below.

4225 on KILOCYCLES

indicator.

Same as step 2.

Same as step 3.

Read audio output voltage

Reading in this step must not ex-

across 300 ohm audio load.

ceed 3.16 times the reading in

step 3.

Same as step1 except set

Same as step 1 except set fre-

Repeat procedure of step 1 at

Record output voltage for re-

output at 6226 kHz.

quency control knobs for

6225 kHz.

ference below.

6225 on KILOCYCLES in-

Change 2 4-3