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Malfunctions are mostly due to improper handling, overload or similar reason.
5.1 Do not use higher input power as stated in the specification. The grid protector
circuit will usually safe the power valves, but OVERLOAD alarm will appear
regularly. This may happening often in SSB mode, especially in case of old
transceivers, when the output power in SSB mode is not adjustable. The 'MIC
GAIN' knob is not fit for power reduction!
5.2 INPUT SWR
The input SWR of the Linear is < 1:1,2.
A well adjusted TCVR will tolerate these values without any trouble.
5.3 OUTPUT SWR
The protection of the Linear will block the transmission in case the SWR of the
aerial exceed 1:2.
5.4 FAILURES
¾ The PA not turn on, nothing happens ON switch is pushed.
ƒ External AC wiring, fuse or circuit breaker may be open.
ƒ Any connector is not in place - cover safety interlock open.
ƒ Fuse F1, F2, F3, F4 open or missing - check fuses with an ohmmeter.
(ME3000-S power supply)
¾ The PA turns on but no HV is indicated by the level meter.
ƒ Possible HV circuit fault.
ƒ HV sampling resistor in power supply damaged. (ME3000-S power
supply)
¾ No idle current when you push the PTT (about 100 mA on meter).
ƒ Not Ua voltage. Check the protection resistor on power supply.
Check the Q1 (BD249C transistor on control board).
¾ The base current is too low or too high.
ƒ Check the control PCB board. Check the Q1 (BD249C transistor and
the zener stabilizer circuit PCB, you can set the needed value with poti
on zener PCB).
¾ You can indicate normal Ia current on meter when drive PA but no output
power.
ƒ Check the output coaxial relay.
10
5.0 TROUBLESHOOTING
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