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Re: Hosfelt snubber caps

Hi David,

	Those big puppies will take like 15 amps RMS each!  Overheating them with
an NST is simply not an issue.  As long as you use at least 7 per string to
get the voltage, you will be perfectly safe.  If they screw down, you may
want to figure out a way to easily change them around to different values. 

DigiKey (www.digikey-dot-com) sells 10 Meg 1/2 watt resistors (10MH-ND) for
about two pennies each.  Use two in series across each of these big caps to
get the voltage standoff.

Yours are the MMC caps the rest of us dream of ;-))



At 06:24 PM 9/8/00 -0400, you wrote:
>Hi Terry, all,
>I was just letting everyone know that I finally broke down and 
>ordered 60 of those 0.1 uFD, 3000 VDC snubber caps from Hos-
>felt today,that was discussed on this list a couple of months ago. 
>I'm wanting to replace the current 0.018 uFD, 60 KVDC Chicago
>Condenser single unit cap that I am currently using in my 15/
>90 NST driven system as it seems very lossy and heats up in
>a short order after the coil is turned on. I am also wanting to re-
>do the primary and secondary coils for a more efficient design
>(I guess I am pretty much rebuilding the whole coil). Anyway,
>I have a few questions to place on the list regarding the use of
>these caps as an MMC.
>First, I was thinking of going w/ 4 strings of 15 (60 total) for a 
>total value of 27nFD -at- 45 KVDC. This will be my 1st real at-
>tempt -at- a MMC cap and I was wondering if 4 strings of these
>would be enough to handle the current of a 15/90 NST bank?
>Without going into the mathematical equations, I figure on ~
>5 nF per 30 mA as resonant for NSTs. So, I am figuring 27 nF
>should make for a LTR cap setup for the 15/90 NST? 
>Also, I was hoping someone could suggest a good source for
>1/2 or 1 watt, 10 meg bleeder resistors (preferably some local 
>jobber like Radio Shack). Thanks in advance for your answers.
>Safe coiling,
>David R.