[Amps] Capacitor Recommendation Needed

[W6NQ]

You might be able to find some of the heavy duty transmitting mica caps-- 
the ones with ceramic body and cast metal endcaps/flanges.
They pop up on surplus from time to time for very low cost.
....Merit  W6NQ


> I need to insert a 1000pf of capacitance in series with my 80M vertical to
> move the resonant frequency up to the phone band. I have been using a
> vacuum variable, but would like to use it in another project - and change
> to a fixed capacitor. The logical choice would be a fixed 1000 pf vacuum
> capacitor. Failing to locate a fixed vacuum cap, what low loss dielectric
> materials should I be considering given the frequency, voltage and current
> involved. The driving impedance is 40 ohms and I run the legal limit.
> Therefore, currents will be in the 6-8A range ... voltages probably less
> than 500 V.
>