Re: Tesla Coil Blunderbusses

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-uswest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi John,

> I wonder if just observing the gap by eye or with some sort of light
> meter to gauge its brightness might be a quick test that folks could
> use if they don't have a scope hook up.  The coil would be tuned for
> it's best output at low power, then the power would be turned up and
> the gap brightness observed.  Next, the coil would be re-tuned for
> longest spark output, and the gap brightness would be observed to see
> if it gets dimmer.  If it gets dimmer, this would suggest a faster
> quenching, and would suggest that this outward tune point permits less
> energy to return to the primary, either because of greater spark
> loading, or for some other reason.  Often, a more inward tune point
> gives more numerous, but shorter sparks.  I've noticed that numerous
> sparks often gives better quenching than fewer longer sparks, so if
> the quenching improves in the experiment, this would be significant. 
> If the quenching gets worse, then it could mean that poorer quenching
> is desireable up to a point as has been suggested by some in the past.

Myself included. I pondered this apparent paradox over the break. We 
*know* quench is largely dictated by secondary losses so I wonder if 
such tuning would have any effect. Problem is, I'm still wondering 
because I was unable to perform the test. My garage is totally 
unsuitable for a variety of reasons so I simply must find time and 
space to do it here at work. I hope we have an open day this year. I 
would get a grand opportunity to test in the best possible 
surroundings. I'd like to settle the question once and for all.
 
> It is certainly true that the streamer-loaded coil should have a
> rather wide bandwidth.  It will be interesting to see the results of
> your scope observations.

Join the club :(

Cheers,
malcolm