Crown Audio FM1000A - Manual (Page 33)

5–3 Troubleshooting
W WARNING ARNING
5.2 Digital Multimeter Parameters
The following procedures are general in nature; for in-depth service, and repair see
the Service & Support section of this manual.
Lethal voltages present!
Only technically qualified
individuals shoud attempt
troubleshooting or service
procedures
.
If any abnormal readings are displayed for any of the following parameters on the
Digital Multimeter, try troubleshooting in the following manner:
5.2.1 In Ref (Input Drive Reference)
If this indication of drive level is not between 0.4 and 0.8 volts, then:
q Check the exciter to ensure proper power input level of 25–30 watts.
q Check RF input cable for secure connection.
5.2.2 SWR (Standing Wave Ratio)
If the SWR is over 1.5:1, then look for:
q effects of inclement weather such as icing on the antenna and feed line.
q for moisture in the feedline.
q insecure antenna connections.
5.2.3 ALC (Automatic Level Control)
If this indication is not between 4.00 and 6.00 volts for 1.1 kW output, then:
q Check for overheating (see PA Temp fault LED).
q Check for overcurrent (see PA DC fault LED).
q Check for high SWR (see Antenna fault LED).
5.2.4 Power Out
This reading is user adjustable, but for full output should read 1.10 for 1.1 kW.
q If lower than desired, check for proper input drive, and/or proper adjustment
of the Local Power Control (see section 3.1 #6).