measures wrote:
> >If the tube has enough voltage breakdown to handle the
> >fundamental RF voltage without problem, we can be sure it will
> >handle almost any spurious oscillation.
> Surely. The arc that makes the big bang is apparently from B+ to ground.
The component in the B+ chain that arcs is thus the (RF choke?).....?
The destruction can be avoided by fusing the B+ chain with a fast blow
fuse?
Are we sure that these arcs are not simply filth on high voltage
components, and/or over-heated ditto, which then creates a gas plasma
path to ground, with the subsequent accusation of parastitic
oscillation? If the blocking cap shorts to ground, the HT on the anode
shares it's path to ground through the suppressor components, which
could explain scorched resistors.. Remember there is DC on AC in this
case, so the path might not be totally through the obvious inductance
route only.
Have we also established that Joe Ham didn't tweak the bandswitch
instead of the tuning cap while eyes glued to the PEP meter and hearing
that rare one get away? Joe wouldn't admit this in a 1000 yrs would he,
specially if the box was under warranty? (I have occasionally wondered
why the "tuning cap" seems a bit stiff on my green monster, only to
discover, timeously, why!).
Ian, ZS6BTE
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