Section IV. STAGE ANALYSIS OF TEST SET, RADIO TS-1962/ARC-51X

TM 11-662-546-445

XIX.XX, as shown in figure 4-9. (Entire fre-

wires 10-B and 10-C. (Note in the chart that

quency setting of readout mechanism in figure

for 33X.XX, control wires 10-B and 10-C are

4-9 is 211.10 mc.) The tens dial is positioned

grounded also, since the tens digit is the

to indicate a 1, and the tens-digit Autoposi-

same.) In figure 4-9, which shows the tens-

tioner is not operating. The tens-digit Auto-

digit Autopositioner set at 1, there is no

positioner is not operating because there are

groundpath for control wire 10-B to motor-

no closed groundpaths through switch seg-

control relay K2; although the 10-B ground-

path is completed from pin U of J1 and

ment S2 rear to motor-control relay K2. With

reference to the chart in e above, the two tens-

through contacts 4 and 3 of S3 rear, contact

digit control wires which carry a ground for

4 of S2 rear is open. But a groundpath is

31X.XS mc are control wires 10-A and 10-B.

completed by control wire 10-C from pin T of

W ith reference to figure 4-9, it is seen that

J1, through contacts 6 and 1 of S2 rear, to mo-

control wire 10-A (pin V of J1) is closed at

tor-control relay K2. This starts the tens-

contact 1 (slider) of switch segment S3 front,

digit Autopositioner, and the Autopositioner

and that contact 2 of S3 front provides a

operates as explained in h and i above. when

open-seeking switches S2 and S3 rotate to the

groundpath to contact 2 of switch segment S2

position where the groundpaths for the 10-B

rear. At S2 rear, contact 2 of S2 rear is open,

and 10-C control wires are both open, the tens-

and the groundpath is not completed to motor-

digit Autopositioner comes to rest (i above),

control relay K2. In the same manner, the

and the tens dial indicates a 3.

groundpath through control wire 10-B (pin

l. The three other Autopositioners operate

U of J1) is completed through switch seg-

in the same manner as does the tens-digit Au-

topositioner. Any number of the Autoposi-

ment S3 rear, but the path is broken at S2

tioners can operate at the same time, and one

rear. Since none of the other three control

Autopositioner can come to rest before one or

wires (10-C, 10-D, and 10-E) are grounded,

more of the others do. Diodes CR1 through

there is no groundpath to motor-control relay

CR4 provide isolation between the solenoids

K2, and the tens-digit Autopositioner is not

(L1, L2, L3, and L4) of the Autopositioners by

operating.

preventing the energizing of a solenoid in

k. Now assume that

a new frequency selec-

one Autopositioner from also energizing the

tion is made in which

the tens digit changes

solenoids in the other Autopositioners. Lamp

from a 1 to a 3. With

reference to the chart in

DS4 indicates a 0 when ground is applied to

above,

the

two

tens-digit

control

wires

control line .00-.05 (pin S of J1) and a 5 when

which carry a ground

for 23X.XX are control

control line .00-.05 is not grounded.

Section IV. STAGE ANALYSIS OF TEST SET,

RADIO TS-1962/ARC-51X

1-21. General

bench +27.5-volt dc supply to pins A and C

of PWR jack J5 (C is- ground). POWER

This section describes the principles of op-

switch CB1 is a circuit-breaker switch that

eration of the test unit, and includes a stage

automatically

shuts

o f f w h e n overloaded

analysis of the various circuits to assist the re-

with 15 amperes or more.

When POWER

pairmen

while

troubleshooting

the

switch CB1 is set to RESET ON, the +27.5-

equipment.

volt dc primary power is distributed to the

1-22. Primary Power Distribution

following places:

(fig. 4-10)

a. Indicator lamps DS1, DS2, and DS4.

The test unit uses and distributes +27.5-

b. Power input terminal E3 of audio ampli-

volt dc power. This power is applied from the

fier 3A1.