> 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.
Virtually 100% of the time this is caused by the T/R relay being too
slow in the amplifier, or the rig "hot-switching" by outputting RF
before it tells the amplifier to "turn on". It is a virtual certainty it is
not the bias system.
What happens is the SWR shutdown falses during the relay
transition, and you see the tailing edge of the SWR protection as
the capacitors in it discharge.
Swap rigs if you can, and see what happens.
73, Tom W8JI
W8JI@contesting.com
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