Topband: 200pF HV-capacitor for shunt feeding

[Tom Rauch]

>> If I were to begin running something close to the legal
limit on 160, I've
> been assuming that the voltages at the bottom of the shunt
feed would
> exceed this rating.  My question is whether I would likely
need vacuum
> variables in both positions or only in place of the series
> capacitor?

It's reactance times RMS current through the reactance times
1.414 times safety factor.

http://www.w8ji.com/omega_and_gama_matching.htm

If you know the RMS voltage it would just be E times 1.414
times safety factor. I like to use 2:1 safety factor.

Good grades of RG-8 will handle maybe 5 kV peak best case if
you do the ends correctly.