TM 11-5805-424-15/NAVSHIPS 0967-220-9010/TO 31W2-2G-41
c. Troubleshooting Chart - Continued
Item
Symptom
Probable trouble
Corrective measure
No.
12
Loss-of-transmit-carrier alarm
a. Defective INPUT SELECT switch
a. Check switch; replace, if defective
activated with INPUT
1A1S5 (fig. 2-3).
(fig. 8-28).
SELECT switch in any
b. Defective ORDER WIRE SEND
b. Check jack; replace, if defective
position.
jack J1(fig. 3-1).
(fig. 8-28).
c. Defective feedthrough capacitor
c. Check capacitors; replace, if
C10, C17, or C18 (fig. 6-29).
defective (fig. 8-28).
d. Defective amplifier DIA-1 on PC
d. Take voltage and resistance meas-
assembly A12 (fig. 8-17).
urements of Q 1-Q4 circuitry; replace
defective components (fig. 6-13).
e. Defective circuit in transmit
c. Troubleshoot transmit section as
section:
follows:
(1) Defective frequency divider
(1)
Check for square wave output
module PC assembly A18A2-
at test jack J2 on PC 80034200
A32A2 (if used) (fig. 8-22, 8-23,
or 8-24).
6-23); PC 80034180 (fig. 6-24);
if not present, troubleshoot
countdown chain FFC-1, FFC-2,
and FFC-3 (para 6-5), and
amplifier IN-1 (para 6-7a);
replace defective components.
(2) Defective 64 divider module
(2)
Check for square wave output
assembly A7 (fig. 812).
at test jack J2 on PC 80034130
for square wave at TP6 through
TP1, in turn, and trouble-
shooting countdown chain
FFC-4 through FFC-9 (para
is present at TP1, check ampli-
fier IN-2 (para 6-7a). If output
is present at J2, check amplifiers
AM-3, AM-4, and PSA-1 (para
(3) Defective transmit filter FL2
(3)
Check for output at pins 8 and
(fig. 2-6).
10 of connector A18PI-A32PI
of MX-73(*)/G (fig. 6-28). If
no output is present, replace
FL2.
(4) Defective resistor AIR16
(4)
Check resistor; replace, it de-
(fig. 8-28).
fective (fig. 8-28).
(5) Defective OUTPUT LEVEL
(5)
Check resistor; replace, if de-
ADJ resistor 1AIR6 (fig. 3-1).
fective (fig. 8-28).
(6) Defective output amplifier Q1,
(6)
Check for output signal at test
Q2, Q3 on assembly A6 (fig.
jack J2 on PC 80034120 (fig.
former 1AIT2 (fig. 6-34); re-
place, if defective. If no output
at J2, check voltage and resist-
ance of output amplifier circuit
(Q1, Q2, Q3, fig. 68-34); replace
defective components.
(7) Defective diode CR12 or CR13
(7) Check diode voltage and resist-
on assembly A6 (fig. 8-11).
ance (fig. 6-34); replace diode,
if defective.
6-45
