Hans, you've raised a number of interesting points here, please help me
out..
> To avoid the problem I always try to keep my microphone gain down just below
> the point where the ALC starts to show up on the rigs meter in the ALC
> position. I will still get maximum pep output but a little less compression
> from the ALC. Remember the COLLINS rigs that had dual ALC constants? They
> had a little compression from the ALC too.
1. The "problem" seems to be the rising spike on initial TX. Has it been
established that this spike is NOT present (even at reduced amplitude)
if the mic gain is a bit lower (or the RF power level is set lower)?
2. Does the ALC produce "compression" or simply limit the PEP?
"Compression" is normally used in the audio stages to boost the low
audio levels a bit.
> In 1958, my old 75A4 had a similar problem. There was always an overshoot
> before the AGC set in on strong signals. For some reasons, there was too
> much IF gain, I remember. Even the famous 51S1 has a very bad AGC on SSB:
Do you see AGC and ALC as the same thing?
Ciao,
Ian ZS6BTE
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