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Re: Any info available on Vacuum Gaps?



>         Not to quibble, but please explain the breakdown mechanism in the
gaps
> which "quency well".  I believe that the pressure in commercial vacuum
> capacitors is more nearly 1E-6 than 1E-9, so don't see how your gap (as
> contrasted to a vacuum relay) could work in the same sense as a gap in
> air.
>
> Ed

Ed,

A vac gap is not the same as either a vacuum switch or a vacuum capacitor
All are
designed for different purposes.   A true manufactured vacuum gap is
designed for
ultra rapid quench and extremely infrequent operation.  TR switches are vacuum
gaps, but are made for continuous operation at low average power
disappation. (not
what I am taking about.)  Vacuum arc break down (protection) gaps are
designed to
indeed work in the 10E9mm range.  Most are trigger type gaps design for pico
second quenching.  Most all rely on field emission for avalanche or
radioactive
deposition the arc lasts until the original high energy source is removed
by any
number of mechanisms. (usually related to additional sensor circuitry or
discharge
of the firing capacitor)  Krytrons and Sprytrons (EG&G) are a good example.

I am unaware of any vacuum gaps having ever been made for continuous high
average
power arcing operation.  This is why it would be wise to discourage any
attempt at
casual construction which would be virtually impossible.  Especially at
very high
average powers.

A vacuum switch relies also on extremely infrequent service and a vacuum
capacitor
relies on never approaching breakdown (hopefully by careful design).  They
function well at 3 orders of magnitude higher pressures.

Richard Hull