What transceiver are you using? Is the polarity of the ALC voltage
compatible with your transceiver?

I use an AL-80B. It has an ALC range of 0 to -10 vdc. My ICOM has a max
ALC of -4 vdc. I set the AL-80B for -4 vdc at max setting. Then I
adjusted the ALC SET on the front panel to activate at approximately 70
watts of drive.

The point I'm making is that two adjustments were required. First set
MAX ALC voltage, followed by setting ALC SET threshold.

wrote:

Hello Rick,

Your assessment matches the manual, however if you have any specifics
on the adjustment that would be helpful. (When I said power down the
radio I did mean decrease the output power on the radio).

Do you need to drive the amplifer with 70W+ or will the ALC control
work with 30W drive from the radio?

I followed that same process, however did not notice the "drop" in
power on the amp or tranceiver when adjusting the ALC adjustment on the
back of the AL-811.

Thank-you
Lloyd