There were a couple of questions about RF chokes. They are used between the
HV primary supply and the primary resonant circuit to keep the high voltage,
high frequency currents from getting back to your transformer and frying the
insulation. The design isn't critical since I don't think it alters the
primary tuning or any other circuit parameter (with the possible exception
of transformer loading...has anybody investigated impedence matching with
the primary transformer?). To use the RF chokes, they would simply connect
the primary transformer HV output (one per terminal) to the rest of the
primary circuit. The three main schools of thought on the matter of RF chokes
I've heard of are:
1. Use 10-20 turns of wire around a 1"-3" air core form (low inductance).
2. Use 3 to 4 layers of wire wound around a steel core (high inductance).
3. Don't use 'em, they're esentially useless on low powered systems.
I use option #1, but then I've burnt up a couple of neon sign transformers
in my time so I might not be the most credible source. I've wondered about
high inductance chokes, but I haven't gotten around to trying anything out.
Any knowledgeable comments about the relative merits of the differrent chokes
would be most welcome.