gap questions

        gap questions
        Sun, 13 Apr 1997 14:16:07 -0500
        Mike Hammer <mhammer-at-misslink-dot-net>
        Tesla List <tesla-at-pupman-dot-com>

Hello all,

After seemingly finding the power limit of
my RQ style gap made from rather small electrodes
I decided to build a larger version and help with
the quenching by pulling hi speed air through the teeth of the gap
with a strong vacuum cleaner motor.

The gap by itself works better than my old gap probably
because of the larger electrodes but when I pull the air
through with the vacuum motor things begin to act differently.

I normally get about 34 inches of spark from a 16 X 4 toroid
and running 12kv/90ma neon with my old gap. The new gap gets me
up to 38 inches. When the vacuum motor is running I get shorter
streamers but more of them. I was using a foil bump on the toroid
to direct the discharge and was getting only a single streamer.
Now I get 2 or 3 streamers even with a very pronounced foil bump.

Also I get some splitting and sparks from the middle of the secondary
that disappear when the vacuum motor is turned off.

I feel the coil is processing more power with the vacuum gap
but I need to know how to get back to a single streamer.
Should I reduce the coupling a bit by raising the secondary?

Is there something here that I'm missing?

Any thoughts on this much appreciated.

Mike Hammer