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Weekend experiment on small coil
Subject: Weekend experiment on small coil
Date: Mon, 12 May 1997 09:47:39 -0500
From: David Huffman <huffman-at-FNAL.GOV>
To: Tesla List <tesla-at-poodle.pupman-dot-com>
Hi Group,
Here is my weekend experiment.
Secondary coil 1.5" dia 4.5" long 24Ga magnet wire, approx. 200 turns
with an inductance of 475uH. Using a 4"X16" toroid for a top load
Csec= 18pF, Fres=1.7MHz. I used 5.6pF ceramic caps and about two
turns of 3/16" Cu tubing with a 12KV-at-60mA neon. Best streamer
discharge was 5-6".
Some things that happened.
I had to play with the coupling, raising the sec., to eliminate a
corona cone from the top of the sec. to the primary coil.
The system was cobbled together, nearly falling over a few times, and
the clip leads making the primary to capacitor-spark gap became
fairly hot after only a couple of minutes of operation. Primary was
low inductance, only a couple turns, and hard to tune.
The streamers were more singular and flame like in appearance (not as
forked) and blue to violet in color.
I needed a breakout point on the toroid to get any streamers.
It was clearly evident that much of the power from the neon was not
going into the secondary. When I use the same capacitors, spark gap
and neon on my bigger coil the connections and gap are noticeable
cooler and sparks 3x longer. The gap is most certainly not quenching
and the losses do to parasitics are substantial.
Just adding information, many already know this stuff others may not.
Dave Huffman