> have 100% proof that the suppressor was the cure. In any
> case, the aformentioned scenario could explain why there is
> a body of anecdotal evidence that the nichrome suppressors
> have provided a cure for high failure rate amplifiers when in
> fact the suppressor had nothing to do with the failure. Of course
> in the few case I have seen cited where the improved stability is
> directly observed (smoother tuning, no signs of oscillation), this
> pitfall doesn't come into play (I seem to recall that VK6APK
> recently cited a case where the nichrome suppressors helped
> stabilize a squirrely homebrew amplifier, but again this amp
> exhibited poor tuning and tendency towards non-catostrophic
> parasitic oscillation - e.g. no tube failure was involved).
How soon we forget things like that.
Lowering operating frequency Q, which is what nichrome does, will reduce the
tendency for sharp tuning. It just doesn't do much for VHF operation.
73 Tom
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