[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

*To*: tesla-at-pupman-dot-com*Subject*: RE: JF efficiency theory (again)*From*: "Tesla list" <tesla-at-pupman-dot-com>*Date*: Tue, 20 Feb 2001 11:33:14 -0700*Resent-Date*: Tue, 20 Feb 2001 11:41:58 -0700*Resent-From*: tesla-at-pupman-dot-com*Resent-Message-ID*: <wlfbaB.A.CQG.xprk6-at-poodle>*Resent-Sender*: tesla-request-at-pupman-dot-com

Original poster: "sundog by way of Terry Fritz <twftesla-at-uswest-dot-net>" <sundog-at-timeship-dot-net> Hi All, Ed Nothing magic about it. John is trying to reduce gap losses by increasing the inductance of the primary, which reduces the surge current and RMS current respectively. Wether or not I agree with it, I dunno. If you're striving to get every last bit of performance out of a given input power, it probably can't hurt to use a higher-inductance secondary and primary. In my case (the LTR pig), gap losses don't even concern me, it's controlling the RMS current that is important. The driver will have close to 1000 turns on it, and the extra coil will have 1000+ turns (1200 or something like that, I can't remember what I figured) because I need the inductance. But with high # of turns comes higher resistive losses. Larger wire counteracts that, but I got a nagging feeling the losses will stay around linear as you scale the size of the coil up (IE. 1600 turns of 32 ga would be just as lossy/resistive as 1600 turns of 16ga on a porportionally larger form). I may (and probably am) wrong, but I'm an MIS, not an EE :) Now, what I will admit is a downside to this approach is size. Especially for higher power levels. A large primary is exactly that, large. 15 turns of 1/4 tubing spaced 1/4" with an 11" center diameter is a big spiral. Ppl have gotten excellent results from a few hundred turns to several thousand (Marc M. 3k turn coil), so I guess it's more a matter of personal preference. Hope it helps! Shad -----Original Message----- From: Tesla list [mailto:tesla-at-pupman-dot-com] Sent: Tuesday, February 20, 2001 1:08 AM To: tesla-at-pupman-dot-com Subject: Re: JF efficiency theory (again) Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-uswest-dot-net>" <evp-at-pacbell-dot-net> Tesla list wrote: > > Original poster: "Mike Novak by way of Terry Fritz <twftesla-at-uswest-dot-net>" <acmnovak-at-msn-dot-com> > > First off, If you haven't done so already, read through > http://hometown.aol-dot-com/FutureT/page5.html > > I was wondering why some coilers get such good results when completely > disregaurding such details. For instance, Ross Overstreet's coil: > 6"x24" wound with #22 for a total of ~880 turns, a primary of approx 7-8 > turns (from the photo) and ~2.2kVA input along with a static gap. He gets > 6-7 ft sparks which is just about right from 1.7(sqrt(input power)). > However, he's only using half the reccommended number of turns on both the > primary AND secondary. Is it possible that it is not the NUMBER of turns, > that maybe it's simply proportionate on some level? What is supposed to be magic about 1600 turns? As long as the primary and secondary are in tune, the inductance only affects the resonant frequency for any given secondary geometry and primary capacitor. Ed

- Prev by Date:
**Re: Mot DC Ps** - Next by Date:
**Re: VTTC output** - Prev by thread:
**Re: JF efficiency theory (again)** - Next by thread:
**Re: LTR Pig Project -biggg coil** - Index(es):