> Original Poster: Esondrmn-at-aol-dot-com
> A counterpoise is a good alternative to an earth ground for a small coil.
> did not say how much power you are running. If the supply is 12 or 15 kv at
> 30 or 60 ma, I would think a counterpoise would work well, especially for a
> portable, indoor type coil. A couple of chunks of mesh metal screen or
I've actually been running a counterpoise instead of a "real" RF ground,
without knowing it. I have a square lid from a cookie tin under the coil,
connected to the base of the windings with 20 AWG stranded. And it seems
to work well enough, although it is not optimal in any way. 12" sparks to
ground with 140W in (4 kV, 35 mA) and the best part is, I can fit all of it
in a large plastic bag and carry it anywhere very easily.
I suppose I should have a much larger area for it, but for the moment I don't
see much advantage in it - maybe later when I have more power.
(Pics at http://users.utu.fi/slaur/ for the whole cookie jar theme :-))