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Registered Member #546
Joined: Fri Feb 23 2007, 11:43PM
Location: Albuquerque, NM
Posts: 239
I'd look on ebay for the CDE 912 series of polyfilm caps. Amazing1 is very over priced on most things.... but in a pinch they would probably work.... ebay is your friend.
Registered Member #690
Joined: Tue May 08 2007, 03:47AM
Location: New Jersey, USA
Posts: 616
No, definitely do not use ceramic caps of any types, they will not stand up to the high pulse of an SGTC. Go with the CDE caps; they're known to work and won't break the bank (usually $3-4 apiece)
Registered Member #546
Joined: Fri Feb 23 2007, 11:43PM
Location: Albuquerque, NM
Posts: 239
$750 is a good deal on a 0.1uf 20kv cap? i just got 4 194uf 10kv caps for the same price roughly(for all 4)....I gather these differ significantly from pulse/energy caps... but wow, what a price/Joule increase.
Registered Member #135
Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735
This is a 720VA Tesla coil using TDK 2nF Doorknobs. I have not seen any other coiler yet to get 38" arcs from 720VA input power.
I could not push the envelope as far as I have with any other capacitor. The TDK 2nF 40KVDC capacitor does not even bat an eye at the pulse power, and they are designed SPECIFICALLY for HIGH PULSE. I would love to see someone come up with a design that could best these capacitors. The button terminals are connected directly to the Titanate for minimal inductance. As a designer I don't see a better alternative, that is if you can afford these buggers.
Strontium Titanate doorknob capacitors > ABSOLUTELY YES they are hardcore performers
MICA >>> NO NO NO. The old Sprague 4nF reconstituted Mica Doorknob Capacitors SHORT at power levels exceeding 300W. I Have them, I have tested them, so don't even go there.
I'm posting this because some of you guys are replying without the experience. I have the experience.
Registered Member #160
Joined: Mon Feb 13 2006, 02:07AM
Location: Melbourne, Australia
Posts: 938
Just look for polypropylene high dv/dt capacitors. These work beautifully, low loss and reasonably priced compared to the high end stuff like the TDKs.
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are these capacitors ok?
