RECEIVER SENSITIVITY ADJUSTMENTS.

TM 11-5820-670-30

RECEIVER SENSITIVITY ADJUSTMENTS.

TEST EQUIPMENT AND MATERIALS

Maintenance Kit MK-1035/ARC-131

Signal Generator AN/URM-103

Power Supply PP-2953/U

Spectrum Analyzer TS-723A/U.

All cables are part of MK-103/ARC

TEST SETUP

Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes

for warmup.

EL1AT243

ADJUSTMENT PROCEDURE

1. Set control unit C-7088/ARC-131 mode switch on test set to OFF.

2. Remove cover from A1000 VHF TUNER (para 2-68).

3. Set control unit SQUELCH switch to DIS, mode switch to T/R, and frequency selectors to

30.00 MHz.

4. Set signal generator AN/URM-103 to 30.00 MHz with 8 kHz deviation and 1000 Hz modulation.

5. Lower rf attenuator of signal generator until signal drops off. If sine wave on oscilloscope

and audio voltage on distortion analyzer drop off with considerable static before 0.5 microvolt,

perform steps 6, 7, and 8.

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