> BTW, even 3ma of grid current in an AB1 amp will cause splatter. If you
> can see that much on a meter, the real peaks are a lot worse.
>
> 73....Carl KM1H
Right. By the time you see it on a meter, your signal is often a
mess.
A peak detector with a hold circuit (perhaps driving an LED) would be
a good idea. I also like Ian's suggestion of building the grid supply
like the PA is for AB2 (regulated with a stiff shunt regulator), even
though you plan on running it on AB1.
I pity you on VHF Carl, with all the crappily biased solid state amps
and what-me -worry 4CX250's.
But we will soon get ours on HF when the low bands fill up with ten
to thirty watt drive poorly designed tetrodes driven by 950SDX's, the
150 watt ICOMS, and FT1000's !!!
73, Tom W8JI
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