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TC Troubles



Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>

From Mike Novak...

This is my second try at getting this post through.... we'll see if it
works.


 Hi All,
 This past month I've been constructing a coil to be sold on ebay as a
fundraiser for Skills USA*.  However, things haven't been going all that
smoothly. The specs are listed at the end.  For instance, I blew TWO of
those "indestructable" Hosfelt Snubbers( They had some corona around the
edges and melted into oblivion... I even have a picture :þ (available on
request) This problem was fixed by the addition of a safety gap across the
tank cap itself.  I'm just not getting the output I would like from this
project. That is, to say, I wouldn't at this point put my name on it and
sell it. It looks nice and everything, but the form is equally important as
function. In other words, I only have half a coil so far. I was hoping some
of the more experienced coilers might be able to throw some ideas my way on
how to improve the beast. I'm getting 12" long arcs now at most (and i DID
measure :).


 Secondary: sealed and dryed 4.5" OD PVC wound with 1300 turns of #28
formvar coated with 4 coats of Spar varnish and 1 coat of pour-on shtuff
Primary: 13 turns of 1/4" OD Cu tube spaced at .25" turn to turn, and
approx 60mm from the secondary. (flat spiral) tapped at turn 12 with full
topload with a fuse-holder Tank Cap: 8 hosfelt snubbers in series with
bleeder resistors safety gap 12.5nF -at- 24kVdc (750vac each) PSU: 2 OBITs in
parallel 10kV -at- 46mA total with safety gaps across the pair Gap: Flat RQ
gap with 8" long segments of 1" OD rigid Cu tube spaced at ~.07 each with
12v fan blowing across the whole thing 8 gaps are available but only 3 are
in use thus far Protection: safety gaps listed above, as well as 1kOhm 25W
power resistor wired in series with each HV leg of the PSU.  Topload: 4"h X
12" OD Al Duct toroid (14pF as suggested by TCCad) and 1" X 6"
"pseudo-toroid" made of SOLID Al... very cool

 Thanks,
 -Mike Novak

 *Skills USA (formerly VICA) http://www.skillsusa-dot-org