[AMPS] suppressors

[km1h @ juno.com]

On Fri, 12 Sep 1997 10:39:15 +0100 Peter Chadwick
<Peter.Chadwick@gpsemi.com> writes:
>For some time, I was mistakenly thinking that the nichrome suppressor
>had no shunt resistors fitted, and thus I didn't understand why it was
>desirable to have a steadily increasing Q with frequency. I will stick
>my neck out and say that although a 'standard' suppressor will often
>work, a better result is likely to be obtained by designing the
>suppressor for the amplifier - not just a suppressor for 572Bs, 811As,
>3-500Zs or whatever, but taking into account the particular set of
>parasitic impedances in the plate and grid circuits in that amplifier.
>That suggests that changing things like tank tuning capacitors and
>switches when 'copying' someone else's design may lead to different
>parasitic suppressors being needed.

Agreed Peter. I have suggested that very thing here before.
Tom's suggestion to measure the feed-thru isolation as a pre-cursor to
the network design was a good one and simple enough to do. It would most
likely cut down on a lot of cut and try and smoke in such notoriously
unstable amps as the 3-1000Z, 4-1000A, etc.  Knowing the likely
frequencies of  the potential parasitics is a must for any  "serious" amp
builder. 

73...Carl  KM1H



>It might be possible to design the parasitic suppressor from theory,
>using something like Eesof to model the real components and the 
>layout.
>It's almost certainly quicker to use empiric methods.
>
>73
>
>Peter G3RZP
>
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