I am seeking the correct procedure for adjusting the ALC pot inside an Alpha
77sx. If you are wondering why I'm even bothering with ALC, I just got a
PowerMaster meter primarily to protect the Alpha from excess SW conditions, in
this case >2:1. That Alpha model is one of several amps that will not stop
producing RF if the PTT line drops out, in an attempt to prevent hot-switching
the relays. So PowerMaster sells a small box which I believe is just a couple
of
logic-steering diodes, and it connects to both the exciter's and Alpha's ALC
connectors. Following the instructions that came with the meter requires using
the amp's ALC line and the adjustment should be accurate. I'm assuming that the
correct method for adjusting it is to drive the amp into a close to 1:1 SWR
matched load while using a 'scope trapezoidal pattern to indicate linearity,
and
adjusting Tune, Load and exciter drive power until the grid current, as
indicated on the Alpha's multimeter approaches max, then the front panel red
ALC
lamp should light fully. Is this correct, or have I missed something? I would
much rather trust the wisdom of the Amps gurus than figure things wrong and
destroy $$$ parts.Thanks, John
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