Table 5-3. Radio Receiver-Transmitter RT-980/GRC-171 Performance Tests (Sheet 12 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

TRANSMITTER WIDE-BAND MODULATION

Disconnect audio oscil-

lator from RT-980/

GRC-171 main audio

input. Connect audio

oscillator to RT-980/

GRC-171 DATA IN-

PUT (A10A2J22-A/B).

Set audio oscillator level

DATA INPUT

85 to 95%.

for 0.775 V rms (0 dB

(A10A2J22-A/B)

mW) at 1000-Hz input

to RT-980/GRC-171 as

observed on digital volt-

meter. Determine

modulation percentage.

TRANSMITTER SIDETONE

Connect equipment as

shown in figure 5-7.

Set audio oscillator for

AUDIO OUTPUT

Adjust SIDE TONE

7.75 V rms (100 mW).

2.45 V rms at 1000-Hz

(A10A2J22-N/S)

adjustment if

input to RT-980/

necessary to ob-

GRC-171.

tain required

sidetone audio.

MODULATION DISTORTION

Connect equipment as

Set RT-980/GRC-171

shown in figure 5-7.

REMOTE/LOCAL

Set audio oscillator

switch to LOCAL,

for 1-kHz tone. 0.135-

SQUELCH switch to

V output.

OFF. PTT/

CARRIER TEST

to PTT, and fre-

quency selectors

to 300.000 MHz.

Using distortion analy-

AUDIO OUTPUT

Less than 10%.

zer, measure the mod-

(A10A2J22-N/S)

lation distortion.

5-18