Harris ZX10, Technical Manual

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12/20/11 888-2595-001 6-9
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WARNING: Disconnect primary power prior to servicing.
Section 6 Troubleshooting
ZX Series
PA TEMPERATURE
alarm
(center LED behind
PA module) PA module has experienced a transistor flange temperature >99C.
Allow module to cool, as necessary, and remove from transmitter. Inspect
heat sink for significant obstruction and remove debris, as necessary.
Inspect chassis fans for multiple failed units and/or a LOW FAN SPEED
alarm on controller board. Replace faulty fans, as necessary.
Inspect amplifier front door air filter for significant obstruction. Replace
filter with clean one, as necessary.
Check amplifier rear door to ensure it was not inadvertently left open.
If fault occurs instantly upon transmitter switch on. Suspect faulty PA
backplane or thermistor sensor on PA module. Swap affected PA module
with PA module from adjacent slot. If problem follows module to new slot,
replace PA module. If problem remains in same slot, replace PA backplane
board.
PA CURRENT alarm
(right LED behind PA
module) PA module has experienced a drain current of >22A.
If all PA modules report this alarm simultaneously, problem is most likely
excessive exciter drive and/or other power control misalignment. Compare
exciter drive level against original factory test data report and adjust as
necessary. Verify power control set per procedures in Section 5 –
Maintenance.
If a single PA module reports this alarm, it most likely has a shorted RF
MOSFET. Swap affected PA module with PA module from adjacent slot. If
problem follows module to new slot, replace PA module. If problem remains
in same slot, replace PA backplane board.
Table 6-3 Module Alarm LEDs
Symptom Cause and Solution