TM 11-5840-281-12-1
4-32. ORGANIZATIONAL TROUBLESHOOTING. (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
5.
No radar video and HV ON indicator switch on either control-indicator is not illuminated. Antennas do not scan or
scan erratically. (CONT)
Step 2.
Place MONITOR switch to - 35V position and observe MONITOR meter Indication.
a. If meter indicates - 35 v, proceed to step 3.
b. If meter indicates 0 v, replace 35V voltage regulator card (para 4-39) and
perform receiver-transmitter power supply adjustments (para 4-41).
c.
If meter indicates other than - 35 v, adjust 35V voltage regulator card as
indicated in 1 through 3.
1.
Set up multimeter to measure 35 v.
2.
Connect negative lead of multimeter to J5303 VOLTAGE MON and
connect positive lead to J5304 GND on local control monitor.
3.
Adjust R3427 - 35 ADJ on 35V voltage regulator card for multimeter
indication of - 35 v.
If adjustment in 1 through 3 cannot be accomplished, replace 35V low voltage
regulator card (para 4-39) and perform receiver-transmitter power supply
adjustments (para 4-41).
Step 3.
On local control monitor, place MONITOR switch to + 28V position and observe MONITOR meter
Indication.
If MONITOR meter does not indicate + 28 + 4 v, replace rectifier card (para 4-
39) and perform receiver-transmitter power supply adjustments (para 4-41).
Step 4.
Perform the voltage checks in the table below at the transmitter control unit. MULTIMETER
TESTPOINT CONNECTION
POSITIVE LEAD
NEGATIVE LEAD
INDICATION
+28 4.0 V
J141 + 28 V
J139 LVPS COM
J140 + 12 V
J139 LVPS COM
+ 12 0.6 V
- 19 1.5 V
J139 LVPS COM
J137 - 19 V
J139 LVPS COM
J138 -6V
4-110
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