> I followed your suggestion this evening and tested my
FT1000MP
> MKV with an adjustable external bias on the ALC port. The
ALC
> loop has a lot of gain so the adjustment was very touchy,
but sure
> enough when I got to the point where the external bias
started to
> throttle back the RF output, the hard edges on the
inter-word leading
> edge characters smoothed out and the inter-word clicking
as heard
> on an external receiver stopped.
> turn pot on the adjust pin would do it. There is -9V
floating around
> inside the FT1K MKV, which could be routed to the +13.8V
> accessory jack and used to drive the external ALC circuit.
It's really a shame manufacturers don't install a manual
gain control for the transmitter IF strip. Many radios have
that ALC attack problem. Tells me they never listen to the
modulation or keying of radios they sell.
Another use of preset external ALC bias is on AM operation.
If you run the front panel power control wide open and set
carrier level with the external bias to 1/4 or less of the
PEP, many radios with crummy TX audio sound like a Ranger II
on AM.
You might have to use a series diode on some radios to block
negative coming out of some radios so you don't
unintentionally defeat the radio internal ALC.
73 Tom
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