Re: MOT-powered coil questions

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Binny by way of Terry Fritz <teslalist-at-qwest-dot-net>" <binny-at-midmaine-dot-com>

Has anyone out there tried to build a rotary spark gap using a rotating
insulating disc to Quench the gap?

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, May 29, 2003 10:11 AM
Subject: RE: MOT-powered coil questions


 > Original poster: "Mccauley, Daniel H by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>
 >
 >
 > Greg, Dwight,
 >
 > I think starting off using "any" number of MOTs is tough for a novice to
 > start out.
 > I'd definitely suggest going the NST route for a first coil.
 >
 > Dan
 >
 >
 >  > OK Dwight,
 >  >
 >  > I stand corrected. Apparently, the lower limit for
 >  > spark gap tesla coil supply voltage has yet to be
 >  > established. Perhaps someday under the guidance of
 >  > this sage group, you can dispense with the transformer
 >  > altogether, and fire a coil directly from 120vac wall
 >  > current. However, I'm going to go out on a limb here
 >  > and assume that you are not interested in micro- or
 >  > flea-power coiling for your first effort, nor are you
 >  > interested in sub-kilovolt spark gap research. If I
 >  > correctly understood your initial query to the list, I
 >  > believe you are interested in building a practical,
 >  > MOT-based Tesla coil, and that you are seeking useful
 >  > advice to that end. If this is so, then based on my
 >  > limited experience, I suggest that 4kvac from a pair
 >  > of MOTs is a tough way for a novice to start out.
 >  > Quenching a low voltage/high current arc presents
 >  > difficult design challenges that most newbies would do
 >  > better to avoid. Raising the voltage a bit with a
 >  > level shifter, or by simply using 4 MOTs instead of 2,
 >  > sidesteps many problems and greatly simplifies spark
 >  > gap design. If you'd like to hear more of my
 >  > half-baked ideas on MOT power supply design for tesla
 >  > coiling, please refer to my various primers on the
 >  > subject.
 >  >
 >  > http://hot-streamer-dot-com/greg/MOT_chat.htm
 >  > http://hot-streamer-dot-com/greg/MOTDOC.htm
 >  > http://hot-streamer-dot-com/greg/4pack.htm
 >  >
 >  > Best Regards,
 >  >
 >  > --- Tesla list <tesla-at-pupman-dot-com> wrote:
 >  >  > Original poster: "Edward Wingate by way of Terry
 >  >  > Fritz <teslalist-at-qwest-dot-net>"
 >  >  > <ewing7-at-rochester.rr-dot-com>
 >  >  >
 >  >  > Tesla list wrote:
 >  >  >
 >  >  >  > Original poster: "by way of Terry Fritz
 >  >  > <teslalist-at-qwest-dot-net>"
 >  >  > <dhmccauley-at-spacecatlighting-dot-com>
 >  >  >  >
 >  >  >  > I disagree whole heartedly.  Even 3kVAC is enough
 >  >  > for a reliable spark-gap
 >  >  >  > driven tesla coil.  Plus many of us, Ed Wingate,
 >  >  > Steve Ward, Gary Lau, and
 >  >  >  > others have built
 >  >  >  > very successful tesla coils utilizing only 4kVAC
 >  >  > transformers.  Theres more
 >  >  >  > than enough margin for reliable operation.
 >  >  >  >
 >  >  >  > The Captain
 >  >  >  >
 >  >  >  >  Dan,
 >  >  >
 >  >  > After my "test" minicoil was completed and while
 >  >  > waiting for my France
 >  >  > 4020SE transformer to arrive
 >  >  > I got 3" sparks using a 2KV/20MA transformer pulled
 >  >  > out of a HiPot tester
 >  >  > firing through 2 gaps of
 >  >  > my 21 gap fixed gap assembly. The operation of the
 >  >  > coil was stable even
 >  >  > with the flea power.
 >  >  >
 >  >  > Ed Wingate RATCB
 >  >  >
 >  >  >
 >  >
 >  >
 >  >
 >  > =====
 >  > Gregory R. Hunter
 >  >
 >  > http://hot-streamer-dot-com/greg
 >  >
 >  > _
 >  >
 >  >
 >
 >
 >
 >