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Re: help - topload
In a message dated 99-09-08 05:45:30 EDT, you write:
<< My previous toroid was aluminum ducting, 4" diameter, 16"
> center-to-center. With this, coil tuned at about 7.2 turns and I got
> about 2' or a little of output. No problems with downward strikes at
> all, and no racing sparks. I just made and tried out a 6" diameter, 18"
> center-to-center toroid instead. I tried retuning at 9 turns and got
> massive racing sparks. I even raised the toroid about 3" more than the
> old one and still the same. Where am I screwing up?
> TIA
> -Stan >>
Stan,
I've seen the same effect. It seems that either a too large or too small
toroid can cause racing sparks. You might try lowering the toroid all
the way, and raising the secondary some more, and verifying perfect
tune point. I think the problem occurs when the sparks have trouble
breaking out of the toroid. The voltage builds too high. Try a breakout
point on the toroid. For a 2' spark, that large toroid is kind of too large.
I generally use a ducting toroid of 4" by 17" for up to a 40" spark, a 5"
by 20" for up to a 48" spark, and a 6" by 26" for up to a 65" spark or
longer.
Your original toroid is about the maximum proper size for the spark length
you're getting. If you want to use the larger toroid, you might have to
build a new larger secondary or loosen the coupling a lot. It's also
possible that your gap is not quenching well. The larger toroid will
make it much harder to quench.
I don't think you gave the specs of your system? Hard to really give
a good answer without them, so my comments above cover a number
of situations.
Just some thoughts,
John Freau