Power Distribution

nal level at this test point, with a 20-milli-

the output of oscillator Q1 (in A10) to be

volt, 65-mc signal injected at the ANT

checked. A typical rf signal level at this

connector, is 40 millivolts. Test point J4

test point is 0.2 volt. Test point J3 permits

permits the amplified output of A21 to be

the output of oscillator Q2 (in A10) to be

checked. A typical signal level at this test

checked. A typical rf signal level at this

point, with the same input as above, is 600

test point is 1.8 volts.

millivolts.

j. Module A11. Module All has one test

r. Module A22. Module A22 has one test

point: J2. Test point J2 permits the output

point: J3. Test point J3 permits the am-

of the discriminator (in A11) to be checked.

plified output of the speech amplifier

A typical discriminator output level, with

limiter to be checked. A typical audio sig-

the fss if. input disabled (by pressing S2 on

nal level at this test point, with a4-milli-

the main frame), is a l.5-volt peak-to-

volt input to A22 (RT-505/PRC-25 in

peak, 10-cps signal.

transmit condition), is 1.8 volts.

k. Module A12. Module A12 has one test

s. Module 43. Module A23 has one test

point: J2. Test point J2 permits the fss if.

point: J3. Test point J3 permits the 150-

output of A12 to be checked. A typical rf

cps output of the tone generator to be

signal level at this test point is 80 milli-

checked. A typical audio signal level at

volts .

this test point, with the RT-505/PRC-25

1. Module A14. Module A14 has two test

in transmit condition, is 0.9 volt.

points: J2 and J3. Test point J2 permits

t. Module A24. Module A24 has one test

sampling the vfo input (from A9). Atypical

point: J3. Test point J3 permits the 150-

rf signal level at this test point is 0.2 volt.

cycle squelch tone signal, amplified in the

T e s t point J3 permits sampling the

frequency-selective circuits of the tone

spectrum generator input (from A15). A

squelch, to be checked. A typical audio

typical rf signal level at this test point is

signal level at this test point, with an rf

a l.5-volt peak-to-peak, l-mc pulse.

signal having a 150-cps modulation de-

m. Module A16. Module A16 has two test

tected by the receiver, or with the RT-

points: J2 and J3. Test point J2 permits

505/PRC-25 in transmit condition, is 1

the unregulated voltage input (12 volts dc)

volt.

from the battery to be checked. Test jack

u. Module A25. Module A25 has two test

J3 permits the regulated voltage output (10

points: J3 and J4. Test point J3 permits

volts dc) to be checked.

the amplitude of the demodulated signal to

n. Module A17. Module A17 has one test

be checked. A typical audio signal level

point: J2. Test point J2 permits the con-

at this test point, with a 20-millivolt, 65-

trol voltage output of All to be checked.

mc signal injected at the ANT connector,

A typical control voltage level, with the

is 180 millivolts. Test point J4 permits

reference frequency input from A10 dis-

the amplified audio output of A25 to be

abled (by pressing S3 on the main frame),

checked. A typical audio signal level at

is +3.6 volts dc.

this test point, with the above signal in-

o. Module A18. Module A18 has one test

jected at the ANT connector and with the

point: J2. Test point J2 permits the fss if.

VOLUME control fully clockwise, is 4.5

output of A18 to be checked. A typical rf

volts .

signal level at this test point is 0.3 volt.

p. Module 40. Module A20 has one test

point: J2. Test point J2 permits the output

33. Power Distribution

of the sidestep oscillator to be checked.

A typical rf signal level at this test point,

a. General. The primary power source

with the RF-505/PRC-25 in transmit con-

for Radio Set AN/PRC-25 can be either

dition, is 0.7 volt.

a Battery, Dry BA-386/PRC-25 or an

Amplifier-Power Supply Group 0A-3633/

q. Module A21. Module A21 has two test

points: J3 and J4. Test point J3 permits

GRC is used when the AN/PRC-25 is op-

the rf input to A31 (from the 11.5-mc crys-

erated in a vehicle. The power distribution

described in b and c below is for use with

tal filter] to be checked. A typical rf sig-