Squelch Control Test - TM-11-6625-601-340015

TM 11-6625-601-34

(rear), contacts 8 and 10 of switch S11D (front),

HOME INPUT jack J1 is applied to the homing

contacts 10 and 8 of switch S10E (front), pin 6

attenuators. Setting switch S1 to LEFT applies

of jack J11, and pin 6 of plug P1005, to the trans-

r f h o m e r signal,

through

a simulated

m i t circuit in the RT-348/ARC-54. Receive

RCVR/XMTR jack J14 and plug P1003, to the

a u d i o from the RT-348/ARC-54 is applied,

homer circuit in the RT-348/ARC-54. The homer

through pin 13 of plug P1005, pin 13 of jack J11,

circuit produces a voltage proportional to the

contacts 4 and 6 of switch S10C (front), contacts

input signal. This voltage applied to the vertical

1 and 11 of switch S11D (front), and contacts 2

pointer circuit in the ID-48/ARN, through pin

and 11 of switch S9B (front), to VOL control R8.

19 of plug P1005, pin 19 of RCVR/XMTR jack

From VOL control R8, receive audio is applied,

J11, and contacts 12 and 2 of TEST FUNCTION

through contacts 2 and 4 of switch S11D (rear),

SELECTOR switch S10E (front), causes the ver-

emitter follower A1Q5, and pin 2 of jack J9, to

tical needle to swing to the left. Setting switch

a headset-microphone. Receive audio common

S1 to RIGHT removes the simulated rf homer

return routes from VOL control R8, through

signal from jack J14 and applies it through

contacts 7 and 10 of switch S9B (front), contacts

RCVR/XMTR jack J13 and plug P1004 to the

2 and 4 of switch S11D (front), contacts 2 and

homer circuit in the RT-348/ARC-54. The resul-

12 of switch S10C (front), pin 14 of jack J11, and

tant voltage produced by the homer circuit and

pin 14 of plug P1005, to the receive circuit in

applied to the vertical pointer circuit in the

the RT-348/ARC-54.

ID-48/ARN through pin 17 of plug P1005, pin

17 of jack J11, contacts 8 and 10 of switch S10C

c. Squelch Control Test. Ground for testing

(front), contacts 1 and 11 of switch S11C (front),

the squelch disable, squelch carrier, and squelch

a n d contacts 1 a n d 2 o f R C V R / X M T R

tone modes of operation originates in the test

FUNCTION switch S9A (front), causes the ver-

set. Setting SQUELCH switch S7 to DIS applies

tical needle to swing right. Setting switch S1 to

ground to the contacts of TEST FUNCTION

ON COURSE applies a simulated rf homing

SELECTOR switches S11E (front) and S11C

signal to the homer circuits connected to jacks

(front). Ground routes, through contacts 5 and

J13 and J14. The ON COURSE position of switch

7 of switch S11E (front), contacts 10 and 7 of

S1 simulates the condition of selecting positions

switch S10D (front), pin 12 of RCVR/XMTR jack

LEFT and RIGHT simultaneously. The voltage

J11, and pin 12 of plug P1005, to the squelch dis-

applied to the needle circuit causes the vertical

a b l e circuit in the RT-348/ARC-54. Ground

needle to move to the center. Reducing the

applied to contact 5 of switch S11C (front)

input rf signal applied to jack J1 simulates the

routes, through contacts 5 and 7, contacts 10

signal strength level. The voltage from the

and 11 of TONE SECURITY switch S8A (rear),

homer circuit in the RF-348/ARC-54 decreases

contacts 2 and 12 of switch S10D (front), pin 8

in proportion to the decrease of input rf signal.

of jack J11, and pin 8 of plug P1005, to the

The reduced voltage output from the homer cir-

squelch carrier circuit in the RT-348/ARC-54.

cuit routes through pins 20 and 21 of plug P1005

Setting switch S7 to CARR removes squelch dis-

and pins 20 and 21 of jack J11 to contact 3 of

able ground from contact 5 of switch S11E

switch S10D (rear) and contact 3 of switch S10C

(front). Ground for operating the squelch carrier

(rear), respectively. The voltage applied to con-

mode of operation is not removed when switch

tact 3 of switch S10C (rear) routes through con-

S7 is set to CARR. Setting switch S7 to TONE

removes squelch carrier ground from contact 5

tact 5 to the horizontal needle circuit in the

ID-48/ARN. The voltage applied to contact 3 of

of switch S11C (front) and applies it to contact

s w i t c h S10D (rear) routes from contact 5,

8 of switch S11C (front). Ground routes, through

through contacts 4 and 2 of switch S11C (front)

contacts 8 and 10 of switch S11C (front), contacts

and contacts 5 and 6 of switch S9A (front), to

7 and 8 of switch S8A (rear), contacts 6 and 4

the horizontal needle circuit in the ID-48/ARN.

of switch S10D (front), pin 9 of jack J11, and pin

This reduced voltage causes the horizontal nee-

9 of plug P1005, to the squelch tone circuit in

the RT-348/ARC-54.

dle to swing down. Operating voltage for the

d. Homer Signal Test. HOME SIMULATOR

ID-48/ARN flags is applied through contacts 2

switch S1 and the homing attenuators, in con-

and 4 of switch S11C (rear) to the flag circuit.

junction with INDICATOR ID-48/ARN on the

Operating ground for the flags is obtained from

test set, provide an operational check of the

the squelch circuit in the RT-348/ARC-54. Dur-

h o m e r circuits in the RT-348/ARC-54. A

i n g the squelch carrier mode of operation,

ground routes, through pin 10 of plug P1005, pin

simulated radio frequency (rf) homer signal

10 of jack J11, and contacts 9 and 11 of switch

obtained from the test equipment connected to

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