> ALC is part of the power control loop, and is not adjustable in rigs
> without a "drive" control.
It's unfortunate that there is not a better way of automatically managing
ALC in most radios. Although I like the ability to manually adjust drive
level on the IC-7800, I think many operators just instinctively want to see
ALC action on both CW and SSB. So, it's a double-edged sword: when used
correctly, its a wonderful tool. But my measurements show that if ALC is
not monitored and tempered on the 7800, really bad things happen. The
default 4 ms setting is actually quite good if drive is set exactly to the
ALC threshold point. Tuning off to the side when listening on my TS-870 in
a wide 6 kHz Rx BW, things sound pretty much identical when the 7800 is
selected between 4ms, and 6ms. But going down to 2 ms creates some
noticeable clicks. Increase the drive lever further and things go to Hell
in a hurry.
My understanding of the new Ten Tec Omni VII is that in addition to
selectable CW rise/decay time, quite a bit of attention was paid to the ALC
circuit and I believe Gary Barbour indicated to me at the Ten Tec Hamfest
that a dual-speed power loop is part of the design. Anyway, looking forward
to those results.
> I have a question Paul. What ALC level does ICOM say to run on CW? Do they
> tell you to barely run the ALC up with the drive control?
I've gone through the manual, and perhaps I'm missing it but I do not see
any recommendation from Icom. So, it seems the user is left to figure this
out for him or herself.
Paul, W9AC
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