> Sorry, it appears I was confusing the Warrior with another amp...
> maybe the Yaesu, though I don't recall ever seen that schematic.
I'm not sure if all runs of the FL2100 do this, but the FL2100 I
looked at takes a sample of RF after the pi-network and feeds it
back to the input.
Of course in that system the operating Q of the tank circuit mostly
controls phase shift. In that system feedback would be all over the
place as tuning and loading is adjusted. It would also vary with load
I may be mistaken, but I swear this was a topic on this reflector
about six months or a year ago? Someone even had the FL2100
schematic on a web page.
To properly adjust the Heath Warrior neutralization, you can
connect a low power ten or 15 meter RF source (backwards) to the
tank output and measure the voltage at the filament with a diode
detector or scope. Of course you do NOT apply HV or filament
The tank is set to the band where drive is being applied and the
tuning and loading peaked while applying a tiny amount of reverse
The neutralizing capacitor is nulled.
What you will find is a clear sharp null in filament RF voltage when
the feedback cap is set properly. Tank settings have very little
effect on null, which is as it should be.
73, Tom W8JI
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