[TCML] VTTC New Grid Coil Geometry
futuret at aol.com
futuret at aol.com
Wed Sep 17 19:20:35 MDT 2008
Hi Dr. John,
I look forward to the time when you are able to finish the research
work on the coil
and report more findings. It all sounds intriquiing to me.
From: Dr. John W. Gudenas <comsciprof at ameritech.net>
To: Tesla Coil Mailing List <tesla at pupman.com>
Sent: Wed, 17 Sep 2008 7:21 pm
Subject: Re: [TCML] VTTC New Grid Coil Geometry
The pancake grid coil, on initial experiments, seems to be a very
I did find that I could reduce the number of turns on the pancake so
that the variac could be cranked up higher before the voltage was
sufficient to oscillate.
This is a minor advantage as you can run up the plate voltage without
hitting the grid with too much voltage. As with all VTTC tuning was
using the reduced size toroid improved performance greatly. I won't
know exactly how improved, until I get the thing on a lower bench, but
when you have been around these VTTCs it isn't hard to see improvement.
However, the sound and spark quality was consistent with the standard
arrangement. I don't need a staccato controller yet and digital
pictures verify the sword like sparks. What is amazing are the bright
white power arcs and I am not sure yet how long they get. This coil has
no metal except for wires & toroid and is five feet away from the power
0oscillator, however, the tank capacitor is adjacent to the
coil with short leads.
It keeps the coil away from me ( reduce RF burns) and other surrounding
elements that act as stray capacitance or antennas. My next run will
use an HV twisted pair for the grid leak leads.
There is much yet to learn, especially understanding the coupling
Physics of the three coils.
One thing, you are right on. It looks really neat and clean with the
hidden grid coil and flash over is eliminated.
Incidentally, thanks for spinning all the different size toroids. Due
to your efforts I have accumulated a set that stacks like a toroid
John W. G.
John W. Gudenas, Ph.D.
Professor of Computer Science
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