TEST PROCEDURE 044

SB 740-91-01

TEST PROCEDURE 044

RECEIVER-TRANSMITTER, RADIO RT-524/VRC AND RT-524A/VRC

RECEIVER-TRANSMITTER, RADIO RT-246/VRC AND RT-246A/VRC

1. General

This procedure provides a description of special test equipment, fixturing, cabling, instrumentation, and instructions for

performing the inspection and evaluations applicable to Receiver-Transmitter units RT-524/VRC, RT-524A/VRC, RT-

246/VRC, and RT246A/VRC.

NOTE

Whenever reference is made to the RT-524/VRC or RT-246/VRC within this text, the same applies for the

RT-524A/VRC and RT-246A/VRC.

2. Test Equipment/Test Setup

All tests are to be performed under the following environmental conditions, unless otherwise stated:

Temperature:

23degrees +\- 10degreesC (730 i 180F)

Relative Humidity:

80 percent maximum.

All test equipment is to be energized for at least 30 minutes prior to utilization, unless otherwise specified in operating

manual for the test equipment.

All tests are to be performed in an electromagnetic shielded enclosure, if in a high RF field of interference.

An MX-7778 suppressor should be placed in the input power line to the radio undergoing testing in order to protect the

radio from spikes and spurs from the ac-dc power supplies.

On warm-up of the RT-246/VRC and RT-524/VRC, the MHz and kHz band switch controls should be turned vigorously a

number of times to clean contacts on sets that have been in storage for a period of time. During activation of the above

controls, observe whether squelch of the set operates properly without a signal. Both "new" and "old" squelch operations

are to be checked. Also, during warm-up, tone quality should be checked at one frequency in both the "A" and "B" bands.

On RT-246/VRC radios, all ten (10) push buttons should be checked at both 22 and 30 volts. Set should not underor

overshoot. Operation should be several times, not just once for each setting. The limit switch should also be checked. It

should activate between 2 and 5 channels from each end of the tuning bands. Adjustment should be made on at least one

button.

Table B-1 lists the test equipment, and Figures B-3, B-4, and B-5 illustrate the various test setups.

B-31