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Re: Rotary Spark Gap Design
Skip,
You wrote...
<snip>
> Would there be any application of lumped constant delay line theory to
> our problem?
I have a gut feeling that the characteristic impedance formula the
Corums use is not valid (they do admit it doesn't work for all coils).
Up to now, I have done the simple SQRT(L/C) thing effectively
averaging the distributed L and C. I am going to do some experiments
this weekend using resistive terminations to determine where the truth
lies on this. I have previously seen scoped evidence that SQRT(L/C) is
the one, but I think this needs to be proved one way or the other. The
formula the Corums use (Schelkunoff) gives values MUCH lower than the
alternative.
One thing I realized yesterday : we are dealing with structures
that have a VERY low radiation resistance whereas helical antenna
are designed to have a high radiation resistance (effective radiation)
and this might well make the difference (what say you Ed Harris?).
Will post results next week.
Malcolm