Power Supply PP-3518/PRC-47. (A8A5)

TM 11-5820-509-35

(19) On the indexing fixture, set the switch to 8

6-13. Power Supply PP-3518/PRC-47. (A8A5)

and rotate the slug rack control to its 000 position. Set

(fig. 7-12)

the OSC CONTROL switches on the test fixture to 0 and

a. Test Equipment and Material.

00; then adjust inductor L73 (fig. 3-96) for maximum

(1) Ammeter, AC (0 to 5 amperes)

output voltage.

(2) Ammeter, DC (0 to 1 ampere)

(20) Repeat step (8).

(3) Ammeter, DC (0 to 15 amperes)

(21) On the indexing fixture, set the switch to 9

(4) Oscilloscope AN/USM-50

and rotate the slug rack control to its 000 position. Set

(5) Power Supply (24 volts dc), Harrison

the OSC CONTROL switches on the test fixture to 0 and

6434B or equal

00; then adjust inductor L74 (fig. 3-96) for maximum

(6) Multimeter ME-26A/U

output voltage.

(7) Test fixture for PP-3518/PRC-47

(22) Repeat step (8).

(8) Voltmeter ME-30A/U.

(23) On the indexing fixture, set the switch to

10 and rotate the slug rack control to its 000 position.

b. Test Conditions and Equipment Connections.

Set the OSC CONTROL switches on the test fixture to 0

CAUTION

and 00; then adjust inductor L76 (fig. 3-105) for

Before connecting the Harrison

maximum output voltage.

6434B power supply to the test

(24) Repeat step (8).

fixture, set its output voltage to 24.0

(25) On the indexing fixture, set the switch to

2.0 volts dc. Return the power on-

11 and rotate the slug rack control to its 000 position.

off switch of this power supply to off

Set the OSC CONTROL switches on the test fixture to 0

until instructed to apply primary

and 00; then adjust inductor L76 (fig. 3-105) for

power to it.

maximum output voltage.

(1) Connect the ac primary power sources to

(26) Repeat step (8).

the test set with the ac ammeter properly connected to

NOTE

the 115 volts ac 400 Hz mains. (See fig. 6-14.)

Potentiometer R148 may be adjusted

NOTE

to compensate for out-of-tolerance

Observe that the current transformer,

operation. Care should be taken to

if used, has the proper turns ratio for

recheck critical frequencies to assure

the ammeter.

that they remain in tolerance after

WARNING

this adjustment.

Never permit the secondary of the

(27) Disconnect the signal generator from the

current transformer to remain open-

500 KHZ IN jack of the test fixture.

Adjust

circuited with power applied to the

potentiometer R150 (fig. 3-96) for minimum output

primary power source.

Fatal

voltage on the multimeter.

voltages can exist across this

i. Oscillator Control Isolation Amplifier Test.

winding.

(1) Connect the multimeter rf probe to the

(2) Connect the dc power supply to the test

test set VFO jack.

fixture with the 0 to 15 ampere dc ammeter connected

(2) On the test fixture, place the FUNCTION

to the positive (+) lead from this power supply. (See fig.

SEL switch to RCVR, the AVC switch to ON, the LOOP

6-14.)

SEL switch to CLOSED, OSC CONTROL switch S1 to 0

NOTE

and OSC CONTROL switch S2 to 00; then place the

If an ammeter shunt is required with

POWER ON-OFF switch to ON.

the dc ammeter being used, be sure

(3) Set the switch on the indexing fixture (fig.

that the voltage drop and current

6-7) to 2 and rotate the slug rack control to the 000

rating match the dc ammeter.

position.

(3) Connect the remainder of the test

(4) Record the output voltage at VFO jack.

instruments to the test fixture as shown in figure 614.

This voltage shall not be less than 1.0 volt rms.

(4) Remove the top cover from the PP-

(5) Set the switch on the indexing fixture to

3518/PRC-47 power supply module to be tested, and

11 and leave the slug rack control at the 000 position.

install this module in the connector on top of the test

On the test fixture, place the OSC CONTROL switch S1

fixture.

to 9 and OSC CONTROL switch S2 to 00.

(5) On the test fixture, place the HV ON-OFF

(6) Repeat step (4).

switch to OFF, the +23V ON-OFF switch to OFF, and

the VOLTAGE SEL switch to

6-24