RE: tweaking

["sundog" <sundog-at-timeship-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi Richard, All:

  First grab some 1/4" copper tubing, some PVC and wind yourself a flat
spiral primary.  That'll cure a lot of the sec-pri flashover.  You've got a
short stubby secondary, and not a whole lot of wire on it.  It'll work, and
can produce good long arcs, but tuning is very sharp, and not many primary
turns are used.  The corona on the upper turns can be helped by using a
toroid vs. a sphere.  It helps to protect the last few windings, and may
give you a bit more streamer length (more capacitance.)  Removing turns
won't help any, you'll just stream corona off the "new" last turns.  Your
ground sounds good to me, especially if you're soaking the ground around it
good.  An MMC would probably behoove you a bit too.  I'm using strings of 11
(panasonics) for ~5nf a string.  You can add to res or LTR, but buy enough
for LTR.  Wintesla says 19.9 is resonant, so 4 strings would do it.  Also,
does your gap have a fan blowing on it?  I saw a pretty good increase when I
added forced air.

   Thy those things first, maybe 1 at a time.  I definately recommend an MMC
tho...Ask either Terry* (I believe he's getting out of the bulk buying
though...) or Dave at D&M's High Voltage.

  http://home-dot-netcom-dot-com/~davmckin/DMsIndex.htm

Terry uses Panasonic and Dave uses a different brand, but they both perform
well!


                    Good luck and keep it up!

<<* I don't have any caps. - Terry>>
										Sundog
-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Monday, July 31, 2000 2:08 PM
To: tesla-at-pupman-dot-com
Subject: tweaking


Original poster: "Richard Barton" <richardbarton-at-caving5.freeserve.co.uk>

Hi all
	I'm at present perfecting my smallish coil to achieve its best
performance. It's powered by 12/90 NST (3 in parallel), running into
a 6.5 turn copper 1/4" pipe primary, through a 8.5nF beer bottle cap,
with a 5 stage stationary spark gap. One of the gaps can be adjusted
whilst running, through a worm-screw and insulated rod. The Secondary
is around 650 turns of 28 SWG and is about 10.5 inches long. The
Secondary form is white ABS, 4 inches diameter.
The primary is a cylindrical shape, supported on 6 insulated struts.
I'm getting just on 10" of noisy white arc to a grounded ball. The topload
on the coil is a 2" polished steel ball (chromium plated). I've tried bigger
toploads but the power seems to diminish.
The primary and secondary are pretty closely coupled, with the occasional
arc across. (I have safety gaps). I get a fair bit of brush discharge from
the
top few windings of the secondary. (White, with a bluish tinge).
In order to improve the output, should I remove a few windings from the
top of the secondary ? Will this stop the wasted leakage from coming from
top windings and get all the power into the topload ?
If I adjust the tapping from the primary coil, it doesn't seem change the
output,
even with half-a-turn of adjusting ! My RF ground is a 5 ft steel rod
hammered
down to almost ground level in sandy soil, watered with a hosepipe,
connected
to the system with car jumper cable, and clips.
Any ideas for getting that bit more power ?
						Richard Barton.