Re: Weird SRSG turn on

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

Original poster: FutureT-at-aol-dot-com 

In a message dated 8/25/04 9:55:55 AM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

Gerry,

I assume your electrode spacing is close at about 0.010" or so?
A very wide spacing can cause erratic operation.

Some combos of NST and cap value can cause a voltage reversal mode
firing that draws a lot of amperage due to a very bad power factor.
Generally larger cap values will tend to suppress this undesireable
operating mode.  Often the best phase position shows the firing
to occur somewhat after the peak cap voltage is reached.  The voltage
is already beginning to fall at this point.  Wide safety gap settings may
be needed to perimit this to occur.  Some NST/cap combos may permit
firing at the peak cap voltage level.

Since each NST brand is different and the applied voltage affects
the phase, etc, the simulations may not be correct.  I would suggest
adjusting the phase over a wide range to see what works best.

I've found that the safety spark gaps should be set rather wide for
SRSG systems.  For example on my TT-42 TC, I set the safety
gaps at about 7/16" for each safety gap for a total of 7/8".  This
is using steel washers on edge.  Large diameter gaps can of
course be set closer.

The phase will need to be different as the variac voltage is raised.
In other words the phase setting that is best for a 20" spark output,
will not be best for a 40" spark output.

I would think the single ended measurements would be OK.

Gary Lau's 15/60 NST srsg coil gave 66" sparks at Ed Wingate's
Teslathon, and the sparks could have gone farther.

John