Removal and Replacement of Audio Amplifier A1 (Located in SM-349/ARC-54)

TM 11-6625-601-34

its proper location and secure with four screws

2-11. Removal

and

Replacement of

and flat washers (1).

FREQUENCY-SELECTOR-MC Switch S3

(3) Position the attenuator plate (5) in its

(Located in TS-1967/ARC-54)

proper location and secure with six screws, lock-

a. Remove

FREQUENCY-SELECTOR-MC

washers, and nuts (4).

switch S3 (fig. 212(1)) as follows:

(1) Remove the switch knob by removing

two Allen screws from the knob.

2-9. Removal and

R e p l a c e m e n t of Audio

(2) Tag and unsolder all wires connected to

(Located in SM-349/

A m p l i f i e r A1

switch S3 (28).

ARC-54)

(3) Remove the hexagonal nut and washer

a. Remove audio amplifier Al (fig. 2-11) as fol-

that secure switch S3 to the test set chassis.

lows:

(4) Remove FREQUENCY-SELECTOR-MC

(1) Remove the four screws and flat

switch S3.

washers (1) that secure the audio amplifier

b. Replace switch S3 as follows:

board (2) to the simulator chassis.

(1) Secure switch (28) to chassis with hex-

(2) Slide the audio amplifier board (2) side-

agonal nut and washer.

ways under the counter assembly (3) until it is

(2) Solder all wires to switch as indicated

clear of the simulator chassis.

by tags.

(3) Carefully turn the audio amplifier board

(3) Replace knob and tighten two Allen

(2) until the wires connected to the terminals

screws.

on the bottom are accessible.

(4) Tag and unsolder the wires connected to

and

Replacement of

2-12. Removal

the terminals.

FREQUENCY-SELECTOR-MC Switch S4

(5) Remove the audio amplifier board (2).

(Located in TS-1967/ARC-54)

b. Replace audio amplifier A1 as follows:

a. R e m o v e

FREQUENCY-SELECTOR-MC

(1) Connect and solder each wire to its

switch S4 (fig. 212 (1)) as follows:

r e s p e c t i v e terminal on the audio amplifier

(1) Remove the switch knob by removing

board (2).

two Allen screws from the knob.

(2) Slide the audio amplifier board (2) under

(2) Tag and unsolder all wires connected to

the counter assembly (3) into its proper position

the switch S4 (29).

and secure with four screws and flat washers

(3) Remove the hexagonal nut and washer

(l).

that secure the switch S4 to the test set chassis.

(4) Remove switch S4.

2 - 1 0 . Removal and Replacement of Motor

b. Replace switch S4 as follows:

Control A2 (Located in SM-349/

(1) Secure switch (29) to chassis with hex-

ARC-54)

agonal nut and washer.

a. Remove motor control A2 (fig. 2-11) as fol-

(2) Solder all wires to switch S4 as indicated

lows:

by tags.

(1) Remove the four screws, flat washers,

(3) Replace knob and tighten two Allen

and spacers (4) that secure the motor control

screws.

board (5) to the simulator chassis.

2 1 3 . Removal

and

Replacement of

(2) Carefully tilt the motor control board (5)

FREQUENCY-SELECTOR-MC Switch S5

forward until the terminals at the back are

(located in TS-1967/ARC-54)

accessible.

a. R e m o v e

FREQUENCY-SELECTOR-MC

(3) Tag and unsolder the wires from the ter-

switch S5 (fig. 212 (1)) as follows:

minals.

(1) Remove the switch knob by removing

(4) Remove the motor control board (5).

two allen screws from the knob.

b. Replace motor control A2 as follows:

(2) Tag and unsolder all wires connected to

(1) Connect and solder each wire to its

switch S5 (62).

respective terminal on the motor control board

(3) Remove the hexagonal nut and washer

(5).

that secure switch S-5 to the test set chassis.

(2) Place the motor control board (5) in its

(4) Remove switch S5.

b. Replace switch S5 as follows:

proper position on the simulator chassis and

(1) Secure switch S5 (62) to chassis with

s e c u r e with four screws, flat washers, and

hexagonal nut and washer.

spacers (4).

2-13