Table 5-3. Radio Receiver-Transmitter RT-980/'GRC-171 Performance Tests (Sheet 2 of 17)

TO 31R2-2GRC171-2

TM 11-5820-815-14

NAVELEX 0967-LP-544-5010

CONTROL SETTINGS

OPERATION OF TEST

AND OPERATION

PERFORMANCE

STEP

EQUIPMENT

POINT OF TEST

OF EQUIPMENT

STANDARD

RECEIVER MAIN AUDIO (NARROW BAND) OUTPUT ( Cont)

Connect distortion

analyzer and 600-ohm

load to RT-980/

GRC-171 AUDIO

OUTPUT 1 and 2

(A10A2J22-N/'S).

Set rf signal generator for

Set REMOTE/LOCAL

rf output level 3 V at

switch to LOCAL,

225.000 MHz, 30% modu-

PTT/CARRIER

lation at 1 kHz.

TEST switch to PTT,

SQUELCH switch to

OFF and frequency

switches to

225.000 MHz.

Set distortion analyzer

AUDIO OUTPUT

Adjust RCV AUDIO

7.75 V rms.

FUNCTION control to

(A10A2J22-N/S)

level control to

VOLTMETER.

obtain a main

audio output level

of 100 mW (7.75

V rms across

600-ohm load).

Increase rf signal

Not more than 3 dB.

generator rf input level

to 1.0 V (into 50 ohms)

and determine increase

in audio output from that

measured in step 8.

RECEIVER SIGNAL-PLUS-NOISE TO NOISE RATIO

Set rf signal generator for

rf output level of 3.0 ,tV

at 225.000 MHz, 30%

modulation at 1 kHz. Ob-

serve distortion analyzer

meter. Set the level to

0 dB (some convenient

reference).

Set distortion analyzer

FUNCTION control to

DISTORTION and deter-

mine noise level of 1

kHz signal in dB.

5-8