Hi Mike,
I had exactly the same problem with my Alpha 87 driven by an FT-1000D. The
problem
was not the amplifier - it was a fault in the wiring to the "tx-gnd" phono jack
on
the back of the FT-1000. Fortunately, at least in my case, the problem was NOT
in
the FT-1000 tx-gnd relay, which would have been a pig to replace.
After putting up with the frustration for a short while, output from the amp
dropped
to drive level, when the tx-gnd jack circuit went open all together. I bit the
bullet and did the necessary surgery in the middle of a contest!
73 Bert VE3QAA
Michael Tope wrote:
> We are having a problem with the AL-82 at the local club station.
> For some reason, the output power rise time on the leading edge
> of the vox relay closure is very slow (on the order of 1 second).
> If I manually close the relay before applying RF using the send
> button on the FT-1000D, the CW rise time is normal. If on the other
> hand I use VOX mode to send CW, you can see the power rise slowly
> on the first character. As long as the VOX relay stays closed, there
> is no truncation or power limitiing of the RF envelope.
>
> I suspect something is wrong with the bias control circuit in the
> AL-82 (looks like the amp bias might be slow to come out of cut-off).
> Any ideas?
>
> Thanks,
>
> Mike W4EF...........
>
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