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Re: A Puzzle
From: Greg Leyh[SMTP:lod-at-pacbell-dot-net]
Sent: Friday, September 05, 1997 2:10 PM
To: Tesla List
Subject: Re: A Puzzle
Bert Hickman wrote:
> A light bulb IS a current driven device. and is almost ideal for
> integrating the type of rapid, fast rise-time current spikes associated
> with streamer propagation (as long as the current doesn't take a "short
> cut" and jump around the inductance of the filament). And the bulb is
> operated in the "shielded" region of the top toroid, so ionization
> heating is not a factor. I am familiar with Duane Byland's LED's in
> various places along the resonator.. note that these will NOT permit you
> to measure the peak currents coming off the self-C of the charged toroid
> itself. Further, while the frequency response of LED's is not bad
> relative to a couple of hundred kilohertz, accurate measurement of
> current peaks going into discharges off the top would require much
> higher bandwidth than available with common LED's.
>
> While I might not be able to pick out the peaks using a tungsten
> filament, I have no doubt that the average current measurements are in
> the ballpark. Any thoughts from other coilers?? Are the hot discharges
> coming off big coils only demonstrating milliamp or microampere current
> levels?
When I had my coil setup at the old warehouse in SF(see the July Nat'l
Geographic, Page 94), I installed two wide-bandwidth (20MHz) Pearson CT's --
one on the secondary ground connection, and another around the ground return
wire for a suspended metal claw. The warehouse was rather cramped, and the
claw was only 10 ft. away, so power arcs were the principal form of discharge.
During a typical power arc, the peak secondary base current ranged between
25 and 30A, and the waveform was all but dead after 9 cycles. The peak
current in the claw return was on the order of 20A. The two waveforms seemed
to be in phase, or very nearly so. (possible skew from the chopping action
on the scope?) The RMS current (over 1 sec) for these waveforms was
considerably less of course, on the order of hundreds of mA.
-GL