Isolating Troubles in R-1467(P)/GRC-144(V) and R-1467(P)A/GRC-144(V) Primary Power Distribution Circuits

TM 11-5820-695-35

Item No.

Symptom

Probable trouble

Corrective actions

32 Cannot calibrate the LOCAL

Defective component or wire in metering

Remove amplifier-mixer 2A7 and check

OSC POWER section of the

circuit.

resistance between pin 8 of connector

R-1467(P)/GRC-144(V) and

2A16XA7 and pin 27 of 2A15A2S1B

R-1467(P)A/GRC-144(V) local

(fig. 6-21). Note that resistance

oscillator power metering

varies smoothly from zero to 5,000

circuits (para 3-65).

ohms as potentiometer 2A15A2R5

(fig. 3-18) is varied from one extreme

to the other. Also check for continuity

between pin 9 of connector 2A16XA7

and pin 27 of 2A15A2S1A.

33 Cannot calibrate the FREQ

Defective component or wire in metering

Remove frequency mixer stage 2A8

MIXER CURRENT 1 sec-

circuit.

and check resistance between pin

tion of the R-1467(P)/GRC-

9 of connector 2A16W1XA8 and pin

144(V) and R-1467(P)AGRC-

11 of 2A15A2S1A (fig. 5-21).

144(V) local oscillator meter-

Note that resistance varies smoothly

ing circuits (para 3-65)

from zero to 50,000 ohms as

potentiometer 2A15A2R3 (fig. 3-18)

is varied from one extreme to the

other. Also check for continuity

between pin 11 of 2A15A2S1B and

the E2 CAB GRD lug on top of 2A15.

34 Cannot calibrate the FREQ

Defective component or wire in metering

Remove frequency mixer stage 2A8

MIXER CURRENT 2 sec-

circuit.

and check resistance between pin

tion of the R-1467(P)/GRC-

9 of connector 2A16W1XA8 and pin

144(V) and R-1467(P)A/GRC-

13 of 2A15A2S1A (fig. 5-21).

144(V) local oscillator meter-

Note that resistance varies smoothly

ing circuits (para 3-65)

from zero to 50,000 ohms as

potentiometer 2A15A2R4 (fig. 3-

18) is varied from one extreme to

the other. Also check for continuity

between pin 13 of 2A15A2S1B and

the E2 CAB GRD lug on top of 2A15.

35 Cannot calibrate the MULT-

Defective component or wire in metering

Remove frequency multiplier-osc

OSC section of the R-1467(P)/

circuit.

2A13 and check resistance between

GRC-144(V) and R-1467(P)A/

pin 9 of connector 2A16W1XA13

GRC -144N(V) local oscillator

and pin 15 of 2A15A2S1B (fig.

metering circuits (para 3-65)

5-21). Note that resistance vanes

smoothly from zero to 5,000 ohms as

potentiometer 2A15A2R6 (fig. 3-18)

is varied from one extreme to the

other. Also check for continuity pin

15 of 2A15A2S1A and the E2 CAB

GRD lug on top of 2A15.

(2)

Remove switch 2A15A2S2 protective

3-13. Isolating Troubles in R-1467(P)/GRC-144(V) and

R-1467(P)A/GRC-144(V)

Primary

Power

cover (fig. 3-19) by removing the four nuts and two

Distribution Circuits

screws that secure it to meter panel assembly 2A16A2.

WARNING

(3)

Remove electrical frequency syn-

115 vac is present in R-1467(P)/GRC-

thesizer 2A14 (para 3-49).

144(V) Do not perform any of the

Procedure.

continuity or resistance checks given

(1)

Refer to the chart (c below). Connect

this

paragraph

while

the

the multimeter leads between the two pins listed in the

equipment is connected to the

steps of the sections that were referenced in the

primary power source.

troubleshooting chart (para 3-12c). If the trouble-

Preparation of R-1467(P)/GRC-144(V) and

shooting chart indicates a section but does

R-1467(P)AGRC-144(V).

(1) Remove power supply 2A1 (para 3-40).

Change 6 3-25