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Sync RSG and hot resistors




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From:  FutureT-at-aol-dot-com [SMTP:FutureT-at-aol-dot-com]
Sent:  Sunday, February 08, 1998 8:11 AM
To:  tesla-at-pupman-dot-com
Subject:  Re: Sync RSG and hot resistors

In a message dated 98-02-07 14:29:12 EST, you write:

<< 
> What really surprises and disturbs me is how hot my choke series resistors
> now run.  With my static-only gaps, I was using a pair of 750 Ohm/50W
> units.  These used to run somewhat hot, but smoked in a very short time
> with my sync RSG.  I've gone to 500 Ohm/75W units, but even these begin
> to smell like they're burning after about 15 seconds.  Assuming they're
> dissipating 100W each, that means they're passing 447 mA??!!
 
> Observing the RSG, the gap arcs appear to be about .5" long, does that
> sound right?  (This is the length of the arc before it breaks, not the
> RSG gap spacing, which is about .03")

Gary,

Are you sure the gap arc is being pulled out .5", or is this just the
*fireball* of hot plasma that splashes out from the gap when it fires?
If the arc is being stretched by .5" this is strange.  Are the electrodes
more than 1/4" wide?  I figure maybe the gaps are refiring if they're too
wide.  Refiring gaps will cause a heavy current draw and heat the chokes,
and hurt the performance.  Yet, with the RQ gap in series, this should
stop re-firing from occuring, so it's a mystery to me.  Besides neon
trannies probably don't provide enough current to cause re-firing in 
general.   Maybe a quench problem of some sort, power arcing? 
Although there shouldn't be.   Do the spinning
electrodes get hot?  Maybe the chokes are resonant and heating up?

I'm not sure I remember the size of cap in your system, is it .011uF to
.014uF or so?  If it's a smaller cap, it may have been firing twice per
half cycle using the static gaps, but firing once (of course) using the
sync gap, which would hurt the performance.  I forget also what size
toroid you're using, are you obtaining a different amount of streamers
now from the toroid?  It's an interesting problem.  Forgive me if I've
already discussed some of these issues previously.

John Freau 
 
> Gary Lau
> Waltham, MA USA
  >>