Orderwire Assembly lA13 Fault Detection Circuits Block Diagram Description

TM 11-5820-695-35

meter panel assembly l1A16A8 to change from a green

to a red indication. The grounded alarm input signal

(3)

To Handset H-1l56/U through closed

also activates multivibrator circuit Q1-Q3.

When

contacts of the RING switch, peak limiter B (integrated

activated, the multivibrator alternately triggers the '1.1

circuit IA3) on 1Al3A5, and IC amplifier A2 and filter FL1

kHz oscillator Q7 on lA13A2 and the 1.6 kHz oscillator

on 1A'13A4.

Q1 on 1,A13A5 into operation. The 1.1 kHz oscillator is

(4)

To the remote telephone through

connected to the 1.6 kHz tone output of the 1.6 kHz

emitter follower Q4 on 1A13A2 and hybrid transformer

oscillator through contacts of the TEST TONE and

1A13A7TB1T1.

RING switches. The alternating 1,1/1.6 kHz tone is

(5)

To Transmitter, Radio T-1054/GRC144

distributed to the loudspeaker on meter panel assembly

through closed contacts of the RING switch, and peak

1A16A8 and to the remote telephone to provide an

limiter B, IC amplifiers A,5, A4, filter ,FL1, and

audible indication that a fault has occurred. The 1.1/1.6

transformer T1 on lAlBA16.

kHz tone is distributed to the loudspeaker by emitter

(6)

To through orderwire transmit (TO

follower Q5 and IC amplifier A2 on lAI13A2. The 1.1/1.6

CABLE) through closed contacts of the RING switch,

kHz tone is sent to the remote telephone through emitter

peak limiter B and IC amplifier A5 on 1A113A5, IC

follower Q4 on 1'A'13A2 and hybrid transformer

amplifier Al, filter ,FL1, and transformer T1 on 1A'SAS.

,lA13A7TB1Tl. Momentarily depressing the RESET

h. Test tone is generated by depressing the TEST

switch on the transmitter panel or an external AUDIBLE

TONE pushbutton switch located on the orderwire

ALARM DISABLE switch i(shelter mounted) silences

assembly front panel.

When the TEST TONE

the loudspeaker alarm by disabling multivibrator. The

pushbutton is depressed, ground is applied to the 1.1

CNTRL ALARM indicator on the meter panel assembly

kHz oscillator Q7 on 1A'18A2 causing oscillation and

1A15A8 remains lighted red indicating a fault still exists.

making 1'.1 kHz test tone available at the output of the

The CNTRL ALARM indicator will turn green only after

oscillator. The 1.'1 kHz test tone is amplified by IC

the fault is removed.

amplifier Al on lA13A2, passes through contacts of the

depressed TEST TONE switch, and is distributed as

2-9.

Orderwire Assembly lA13 Fault Detection

follows:

Circuits Block Diagram Description (fig. 5-10))

(1) To Handset H-156/U through sidetone

amplifier Q2 on 1A1,3BA5.

a. The test circuits consist of MODULE TEST

(2) To the remote telephone through peak

selector switch 1A13A1S1, 4.02 kHz oscillator lAISAiQ1

limiter A (integrated circuit A2) on 1A13A5, IC amplifier

and IC amplifier 1A13AlAl, transformer 1Al3AlT'l, 4.02

A2 and filter FL2 on 1A13A3, and hybrid transformer

kHz monitor lAl3A1'Q2 and IC amplifier 1Al3AIA2, and

1A13A71TBlT1.

light switch assembly 1A13A1S2 which contains the

(3) To Transmitter, Radio T-1054-GRC144

MODULE TEST monitor indicator.

Figure 510 is

through peak limiter A, IC amplifiers A5 and A4, filter

arranged for left to right signal flow with the test input

FL1, and transformer T1 on 1A13A6.

circuits on the left and the test output circuits on the

right.

(4) ro the through orderwire transmit (TO

CABI E) through peak limiter A and IC amplifier A5 on

b. With the MODULE TEST selector switch set to

lA13A,5, and IC amplifier Al, filter FL1, and transformer

position 1, the module fault detector circuits are tested.

T1 on 1A1A3.

The output of the 4.02 kHz oscillator is connected to the

4.02 kHz monitor through contacts S1,E-1 and SlE5 of

i. OR gate circuits A and B on 1A13A2 monitor

the selector switch and contacts of the MODULE TEST

summary alarm signal inputs from the R11467/RC-144

indicator press-to-test switch. The 4.02 kHz monitor

(rcvr elm), the T-1054/GRC-144 (rcvr aim), and digital

converts the 4.02 kHz signal into a dc output voltage

data modem iAi12 (pcm aim). A fault in the monitored

which biases the lamp driver in light switch assembly

equipment results in a grounded alarm input to the OR

1A1SA1S2 off: With the lamp driver biased off, the

gate circuits.

OR gate A, CR 6-CR 9, controls

MODUJ E TEST indicator is extinguished indicating

multivibrator circuit Ql'3 and OR gate BX, OR-CR5

that the fault detection circuits are operating normally.

controls transistor switch Q6. When one of the alarm

Depressing the MODULE TEST indicator (press-to-test),

input signal becomes grounded, the transistor switch is

activated causing the CNTRL .ALARM indication on

2-25