Spark Gaps

From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent:  Tuesday, April 14, 1998 4:50 PM
To:  Tesla List
Subject:  Re: Spark Gaps

Hi Jim,

> From:  Jim Lux [SMTP:jimlux-at-earthlink-dot-net]
> Sent:  Friday, April 10, 1998 10:26 AM
> To:  Tesla List
> Subject:  Re: Spark Gaps

> I'm too lazy to go back through everyone's posts on modelling the coil, so
> I'll ask a redundant question: Have you looked at this aspect of the
> gap/primary circuit? Say you modeled the gap as a perfect switch that opens
> and closes in some sort of synchronism with the primary waveform, what sort
> of waveforms are created? in a theoretical sense, at least.

I have done it in practice by replacing the gap with MOSFETs in a low 
powered setup. In essence, you operate in Class C/D for best results.
If the gap fires with each cycle, the coil rings up until losses = 
input. If you do it every 2,3,4 etc cycles, you can see the limited Q 
causing an amplitude decrement between gap fires. Nothing unexpected. 
It is basically CW operation. Phasing and timing is critical (far too 
critical for mechanical gaps of any sort). Any significant output 
loading drags amplitude into the dirt.