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.
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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