TM 11-5805-424-15/NAVSHIPS 0967-220-9010/TO 31W2-2G-41
c. Troubleshooting Chart-Continued
Item
Symptom
Probable trouble
Corrective measure
No.
17
No receive data or bit-
a. Defective amplifier DIA-2 on
a. Take voltage and resistance meas-
timing signals available for
assembly A1 (fig. 8-6).
urements of Q1-Q5 circuitry
external clock operation;
internal clock operation is
components (fig. 6-2).
normal.
b. Defective OR gate GOA-4 or
b. Troubleshoot OR gate (para 6-6d);
GOA-5 on assembly A1.
replace defective components
c. Defective AND gate GAI-4 on
c. Troubleshoot AND gate (para 6-
assembly A1.
6a); replace defective components
d. Defective VCO Q7-Q9 on assembly
d. Check for sine wave output at
A1.
TP6 of PC 80034090 (fig. 6-2).
If not present, check voltage and
resistance of VCO (fig. 6-31);
replace defective components.
e. Defective amplifier IN-14 on
c. Troubleshoot amplifier (para 6-7a);
assembly A1.
replace defective components.
18
No receive data or bit-
a. Defective 1.2288 mc crystal oscilla
a. Replace crystal oscillator assembly.
timing data available for
tor assembly (fig. 1-6).
internal clock operation;
external clock operation is
b. Defective clock module divider
b. Check for square wave output at
normal.
FFC-13, FFC-14, or FFC-15
test jack J2 (fig. 6-26). If not
present, troubleshoot countdown
circuit on assembly A33A2 (para
c. Defective amplifier IN-21 or IN-22
c. Troubleshoot amplifier (para 6-7a);
on PC assembly A33A2 (fig.
replace defective components
8-27).
19
No receive data or receive
a. Defective add-subtract logic
a. Troubleshoot add-subtract circuit,
bit-timing signals available;
circuit on assembly A3 (fig. 8-8):
as follows:
uncorrected transmit bit-
(1) Defective amplifier IN-24.
(1) Check for timing signal output
timing signals normal.
at pin U of assembly A3 con-
nector (fig. 6-4). If not present,
troubleshoot amplifier IN-24
(para 6-7a).
(2) Defective countdown chain
(2) Troubleshoot countdown chain
FFD-1, FFD-2, or FFD-3.
parts.
b. Defective 128 divider-B assembly
b. Troubleshoot divider-A as follows:
circuit on assembly A4 (fig. 8-9):
(1) Check AND gate (para 6-6c);
(1) Defective AND gate GAD-4 or
replace defective components
GAD-5.
(2) Defective bistable FFG-1.
(2) Check bistable (para 6-5);
(3) Defective AND gates GAS-6
replace defective components
through GAS-9.
(4) Defective countdown chain
(3) Check AND gates (para 6-6c);
FFD-5, FFC-23 through
replace defective components
FFC-27.
(4) Check countdown chain (para
nents (fig. 6-5).
Change 3
6-47
