In article , Trevor Wilson
wrote:

"Jim Lesurf" wrote in message

Shouldn't you valve types be using DC from batteries;?...

The only valves I've done PSUs for were klystrons or carcinotrons. I
suspect the battery stacks for those would have been quite large. ;-

**"Carcinotron"? I had to look that one up. A type of travelling wave
tube. I thought I'd heard all the names, but the choice of the name:
carcinotron was sure an unfortunate one.

It was a common description in my experience. I think at least one of the
makers of BWOs (backward wave oscillilators) for 100GHz used it. It may
have been Thompson CSF but I can't recall as it was ages ago.

I assume it was on the basis that the backward wave was - in conventional
TWT terms - a parasitic growth than extracted power from a forward beam
mode. Analogy with the way a cancer growth takes resources from the normal
body processes or disrupts their operation.

So for a conventional TWT it was unwanted, but turned out to be useful for
power at higher frequencies.

Advantage of the tubes was that you could get them up to about a THz, and
they had a wide electronic tuning range. The snag was what brought them to
mind for this thread. The wide electronic tuning range meant that you
needed to control all the applied voltages with exceptional care if you
wanted output stable to a few kHz or better.

Slainte,

Jim

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