I heartily endorse Rick's recommendation of using forward biased silicon
diodes rather than zeners! I've been running a set of six (nearly)
identical 3-1000Z monoband amplifiers in contests since I built them 25
years ago. The most troublesome component in the amplifiers had been the
occasional shorted zener, and I totally eliminated that failure mechanism
ten years ago with strings of inexpensive 2.5 amp diodes mounted on
perfboards.
Except for occasionally cleaning the dust off of the tubes, I've had no
reason to remove the covers from these amplifiers for many years; despite
at least five uncompromising multi-multi contest entries (including
the CQ WW RTTY Contest) every year.
73
Frank
W3LPL
donovanf@sgate.com
>R.L Measures wrote:
AG6K> I would use a series string of forward conducting diodes mounted on
AG6K> perfboard. Diodes can be shorted as needed to adjust the ZSAC to
AG6K> the needed 75mA per anode. The trouble with Zeners is they are
neither adjustable or cheap.
>R. L. Measures,ag6k,805-386-3734
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