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Re: Scopes Away!



Hi Greg,

> > Primary Q without the MOSFETs measured around 24.
> >      With the FETs driven with a gate drive of 8V from a pulse
> > generator terminated with a 50 Ohm resistor at the gate/source
> > connection. Primary Q measured 9 ( from waveform decrement).
> > This is rather close to what you would get with a standard spark gap
> > incidentally.
> 
> Did you notice if the parasitic body diode of the MOSFETs had any
> effect on the quenching action?  It seems like once the energy was
> transferred to the secondary that the FETs could only hold off the
> back EMF in one direction, as the body diode would conduct in the
> other, resulting in all the haversines of one polarity re-charging 
> the primary cap back to some DC value.

It appeared not to. Quenching was as clean as a whistle and the 
secondary ring also looked balanced. I'm going to revisit this for 
other purposes this weekend. I'll recheck this. Now you mention it,
I did forget about this. The scope was on DC.

Malcolm