A5300 SQUELCH FILTER ALINEMENT. - TM-11-5820-401-34-30198

TM 11-5820-401-34-3/0967-LP-432-3060

3-23. A5300 SQUELCH FILTER ALINEMENT.

PURPOSE. This procedure adjusts the gain of Squelch Amplifier A5200 in the NEW SQUELCH mode

of operation. By adjusting Resistor R5301 in the squelch filter, the filter is properly tuned to attenuate

the 150-Hz squelch tone, thus providing maximum degenerative feedback to Squelch Amplifier A5200

for all frequencies other than 150 Hz. This permits the squelch amplifier to provide maximum gain for

150-Hz signals. Alinement of the A5300 squelch filter must be done before the Squelch Amplifier

A5200 Alinement, NEW SQUELCH Level, paragraph 3-25.

TEST EQUIPMENT AND MATERIALS

Matching Unit CN-901/U

Signal Generator AN/URM-103

T-Connector UG-274/U

Signal Generator AN/URM-127

Loudspeaker LS-454/U

Power Supply PP-1104(*)/G

Voltmeter ME-30(*)/U

Frequency Counter AN/USM-207

Maintenance Kit MK-1978/VRC

TEST SETUP. Connect the equipment as shown in test setup diagram

. Remove R-442/ VRC top

INITIAL EQUIPMENT CONTROL SETTINGS. Set equipment as indicated in the following table. When

using alternate equipment, inject 1000-v rf at a frequency which gives maximum TP5008 voltage.

Use variable external modulation around 150-Hz reference. Deviation will vary according to alinement

requirements.

3-112