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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
>>