Re: "Gas burner" corona from STSG driver

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "Kurt Schraner by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <k.schraner-at-datacomm.ch>
> 
> John, Gary -
> 
> To my knowledge, what has been used for X-Ray were induction coils, not
> Tesla coils. Probably John meant this (please correct me if I'm wrong)?
> - The design of those inductors took into consideration, to make the
> secondary sparks voltage-waveform with as low "inverse" as possible,
> meaning a waveform with high DC part. This is elucidated i.e. in
> M.A.Codd, Induction Coil Design, E.& F.Spon, London 1922, reprint
> obtainable by PV-Scientific.

Early X-Ray power supplies were indeed mostly induction coils, but
electrostatic machines were also used for some time, due to the
pure DC output, particularly convenient when the images were
directly observed through a fluoroscope. Some old texts even say that
with pure DC there were no problems with "X-ray burns" (they were
wrong, unfortunately for many experimenters).

About the secondary voltage with as low inverse as possible, this
only makes sense as "without inversions before the spark occurs".
Without sparks (or other nonlinearities) the average output is always 
zero.
The relatively tight coupling of these coils cause the output
voltage to rise to the maximum value at the first swing, while in
a Tesla coil there are always at least one (for k=0.6) polarity
reversal before the output voltage reaches the maximum absolute value.

Antonio Carlos M. de Queiroz