From: boris petkovic
Date: Fri, 17 May 2002 11:52:05 -0700 (PDT)
Subject: Re: [TSSP] Racing arcs
Hi Terry,All, I wrote: if I remember you mentioned one local coiler > of > >yours had flashover accidents with that type of > >setting? Termed that like sort of "transformer" > >action? > >Well,call it the way you want but I'm going to call > >it:"Potato action" (according to a "nice" voltage > curve >profile). Terry wrote: > In my youth trying to build a Tesla coil, I tried a > number of small > primary/secondaries that were more loosely coupled > pulse transformers. No > tuning really just discharge a cap into a few turn > primary with a many turns > secondary in the middle. My small little coil in a > 7 inch diameter jar could > blow right through 3 inches of oil and the glass jar > easily. Yes, the coupling > was low but the load impedance before the spark was > very high so the voltage > shot right up. "i" think the same effect may > account for racing arcs and the > very long (like) one foot primary to secondary arcs > we see when a coil is out > of tune. This idea has never caught on with anyone > but "me" but I figure with > all the work going on the truth either way will be > found soon for sure. > "Potato action" is a little new to me ;-)) but > anyway we can finally figure out > what causes the bazaar powerful arcs is fine with me > :-) In Dave's coil, We > tried to insulate the primary and secondary and > foot+ long arcs just went right > around the insulators. --- Maybe there was misunderstanding about terminology stuff.By "transformer action" I considered voltage transformation V1:V2=N1:N2 characteristic for k~1 magnetic coupled coil circuits (modus operandi distribution tranformers work) and nothing else. As you said ,in your coil and Dave's as well,coupling was low,but detuning casued pri-sec flashowers. I think these cases occure when Fpri>Fsec since simulation shows that nasty local voltage gradients may appear for +50% detuning.Severe Fpritune, you can't get it to > arc an inch... ---- Toroid discharge was so short ,or discharges in some other places? regards, Boris __________________________________________________ Do You Yahoo!? LAUNCH - Your Yahoo! Music Experience http://launch.yahoo.com
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