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Subject: Re: DIY HV Pulse Cap?
Date: Oct 31, 1:53 pm
Poster: Richard Hester

On Oct 31, 1:53 pm, Richard Hester wrote:

Review the discussion on this list regarding ceramic capacitors. High-K ceramics are no good for pulse capacitors precisely because they are piezoelectric, and tend to crack or pull their connections loose under the mechanical stress induced by a fast discharge. Glass may be OK for low rep rates, but has fairly high loss, plus being heavy and a bastard to work with. If I were going to try any alternative to polyethylene sheet, it would be mylar or polypropylene. For very high voltage, both will probably need oil filling to help them out.
Richard Hester
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>Making a stack of glass or better yet, high-E ceramic plates would make for a much smaller capacitor. From what I know of ultrasonic transducers (which are basicaly ceramic or quartz capacitors), the stack will need to be mechanicaly loaded to keep from absorbing the energy, which is stored in the stress of the ceramic.
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>Any references on construction of ceramic capacitors?