Crown Audio FM1000A - Manual (Page 34)

TROUBLE TROUBLE TROUBLE
5–4 FM1000A User’s Manual
5.2.5 PA Temp
The meter should read between 35–50°C with an ambient temperature of 25°C. If
temperature is 75°C or above, then check and do the following:
❑ Ambient temperature higher than 50°C; reduce temperature.
❑ Restricted air flow; remove any obstructions, clean dirty air filters by using
mild detergent and warm water.
❑ Possible antenna mismatch; check for icing, moisture in the feedline, and
secure antenna connections.
❑ Overcurrent: If PA DC fault indicator is flashing, monitor the current for a
proper level—the total current and the current of individual Power Amps.
5.2.6 PA Voltage
Supply voltage to the RF power amplifiers should be 50 V. If it is not check:
❑ drive level to ensure proper power level input of 30 watts
❑ for high SWR
❑ for overcurrent; check PA DC fault indicator and if flashing, check current for
proper levels (total and individual Power Amps)
❑ for overtemperature; ambient temperature higher than 50°C; reduce tempera-
ture. Check air flow; remove any obstructions and clean dirty air filters.
5.2.7 Tot Current
If total current reading is over 35 amperes, then check or do the following:
❑ Reduce power output; check all fault indicators and troubleshoot accordingly.
❑ If one or more of the 250–watt power modules has failed; replace.
❑ High SWR; check for icing, moisture in the feedline, and secure antenna
connections.
5.2.8 PA1–8
If there is 2.5 amps or more difference between the individual PA current readings
(7 to 9 amps typical), then check the following:
❑ Failed/faulty power module (reading directly correlates to failed power mod-
ule); replace.
❑ Blown individual power amplifier fuses 1–8; replace as indicated by red LED.
❑ Reduced power output; check all fault indicators and troubleshoot accordingly.