> Leaving aside the fact that I know the expression as 'teats on a
> bull', doesn't this comment appear to apply to nearly all, if not all,
> ALC systems? The ones in
>
> amplifiers mostly seem to work on the basis of shutting the stable
> door after the horse has bolted.
Group delay in the RF chain is very small, so ALC should work well
from an external PA if the system is designed correctly.
The problem is the radios. The response time of external ALC ports
is generally far too slow.
Hell, they can't even get their own radios to work correctly. Some
of them not only integrate the ALC too much on leading edges,
they also dump the control voltage in way back ahead of the narrow
transmitting filter making group delay an issue.
73, Tom W8JI
W8JI@contesting.com
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