From: Bert Hickman
Date: Wed, 30 May 2001 07:17:00 -0500
Subject: Re: [TSSP] Topics on non-linear effects
Terry, Please send me your mailing address off list. I've got a number of references that should prove useful... -- Bert -- -- Bert Hickman Stoneridge Engineering Email: bert.hickman@aquila.net Web Site: http://www.teslamania.com "Terrell W. Fritz" wrote: > > Hi Bert, > > I have checked out the Ross Engineering VD120 and the Jennings Model 13200. > They seem to be the sort of things that would be good for this. Probably > a 1000:1 divider at 200kV peak would be nice. I assume the new prices are > enormous especially from Ross. I think I have worn out my welcome with > Jennings ;-)) > > It is probably not too hard to make an oil filled homemade version. I have > the precision Bertan that goes to 50kVDC that could simply arc to ground to > make the voltage step for calibration. > > http://hot-streamer.com/TeslaCoils/MMCInfo/GeekCaps/HVTest.jpg > > I would be very interested in any design information or tips for such things. > > Cheers, > > Terry > > At 07:36 AM 5/29/2001 -0500, you wrote: > >Terry, > > > >Ross Electronics and Jennings make similar units, using either compressed > >gas (advantage: no X-Rays) or vacuum capacitors for the HV cap(s). Do you > >have any idea of the expected standoff voltage required? I have a couple of > >Ross units, one rated at 15 kV (off Ebay!) and the other for 60 kV > >(untested - just picked it up at the Dayton HamFest, looks a bit beat up > >though). > > > >It might be possible to make an air insulated HV capacitor, or use a chain > >of vacuum caps with grading rings for the HV section. If you want to try > >"rolling you own", I have some design information that might be useful. As > >you indicate, the key would be in calibrating the thing. Assuming you could > >prevent corona leakage, it may be possible to calibrate it by using a > >precision HV DC supply (say 5 or 10 kV) and then "pulsing" the output to > >the divider via a HV SPDT vacuum relay, driving the divider input to either > >the supply voltage or ground. > > > >-- Bert -- > >-- > >Bert Hickman > >Stoneridge Engineering > >Email: bert.hickman@aquila.net > >Web Site: http://www.teslamania.com > > > > > >"Terrell W. Fritz" wrote: > >> > >> Hi Paul, > >> > >> Capacitive voltage dividers may be the way to go. Something along the > >> lines of the $800 Pearson: > >> > >> http://www.pearsonelectronics.com/Pages/Capacitive_Voltage_Divider.html > >> > >> Unfortunatly, there were none on E-bay... ;-) > >> > >> They have the advantage of being calibrated out of the box (5%) and all the > >> thinking is done. They have 18pF of load. > >> > >> Most places seem to roll their own: > >> http://www.uni-stuttgart.de/ieh/forschung/einrichtungen/v_general.jpg > >> http://www.uni-stuttgart.de/ieh/forschung/einrichtungen/v_Teilentl1.jpg > >> > >> The problem is by the time you get all the electrostatic shields and > >> terminals big enough not to arc, the load goes up too high. However, they > >> are basic physical devices with few tricks and the outputs can be clamped > >> heavily and such for protection. Calibration is not trivial either. I'll > >> think on it. > >> > >> The plane wave antenna is another possibility but it is a wide area device. > >> Perhaps it could be aimed through a tunnel or antenna like array to hit a > >> small spot... > >> > >> I used to repair voltage dividers on 375kV power line equipment (live > >> ==:-| ) but I don't think those types would be any good at high-frequency. > >> > >> Cheers, > >> > >> Terry > >> > >> At 11:37 PM 5/28/2001 +0100, you wrote: > >> >Terry, All, > >> > > >> >Some preliminary notes on your CW brush discharge current > >> >measurements. > >> > > >> > http://www.abelian.demon.co.uk/tssp/tfcw260501/ > >> > > >> >Next step would be to determine what the discharge impedance > >> >is, and how it varies with the steady state voltage. But an > >> >essential prerequisite is a means to reliably capture the > >> >peak topvolts value. > >> > > >> >Without this, we can't establish a pattern for brush discharge > >> >loadings, nor can we confirm ET6.12 predictions of breakout > >> >voltage. So now would be a real good time for budding inventors > >> >out there to get cracking. > >> > > >> >Cheers All, > >> >-- > >> >Paul Nicholson, > >> >Manchester, UK. > >> >-- > >
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.