KM1H stated following:
>That is assuming the manufacturers even use bias John!
>The lack of adequate bias circuits for linear operation of the majority
>of VHF-UHF brick amps is a sore point with many users. It appears that
>only Teletec is using an active circuit that holds up under all drive
>conditions.
>Thankfully, decent circuits have been published allowing a gradual
>clean-up of signals.
>I have it on good authority that a major brick manufacturer will soon
>follow suit.
Actually I didn't even think about the brick manufacturers. I was referring
to drivers or IPA
stages for VHF broadcasting. Yes, not using a good bias circuit (with
temperature compensation) is nasty for bipolar transistor power amplifiers,
especially when they are switched to SSB mode.
>You must have as much fun at your job as Eric does with antennas! It must
>be nice!
While it lasts.... Too much RF might not be good for a chap!
>I get the feeling from your post that the driver circuits for those big
>tetrodes are now SS ??
Exactly.
John
K5PRO
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