High Voltage Section for Marc's STSG

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

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

Hi Marc and All,

I definitely like the GM HEI coil over the Ford.  It seems to have a better
output and having the primary and secondary isolated from each other is a
real plus.  You don't have to worry about adjusting the gap and finding
120VAC sitting on the trigger...  My control box has a neon bulb (fault)
wired between the neutral and ground to detect miswires.  That would make
the neutral go hot.  That would allow 120VAC to ride on all the
non-switched neutral stuff...  I still need to add the nice terminal to the
GM coil as you suggest.

I tested the high voltage section today:

Schematic:
http://hot-streamer-dot-com/TeslaCoils/Misc/MarcMetlicka-STSG/HVSection/HighVolt
age.gif

Picture:
http://hot-streamer-dot-com/TeslaCoils/Misc/MarcMetlicka-STSG/HVSection/HighVolt
ageSec.jpg

Seems to work great.  I still find I need the 25 ohm 400watt load to make
the phase adjustment work perfectly.  Some people say they can use less but
maybe better check with a scope.  With 50 ohms it seems ok but there is
jitter and loss of phase going on you would not notice.  With 25 ohms it is
rock solid.  Hopefully, someone can figure out how to eliminate them.
Maybe by rewiring the dimmer as Gary suggested.  I wonder if a "ceiling
fan" dimmer would be better.  I can't find any around here but maybe I need
to look harder.  They look expensive...

I am using two 1uF 250V caps from Radio Shack (272-1055) but I don't know
if they are proper for this.  Maybe Ted can check around and see how the
Shack specs them.  If not, DigiKey has some with a ton of safety ratings
for $5  The ones from Radio Shack have not burst into flames yet :-)

I should mention that you may not need the filter in yesterday's
Controller.  I have two computers about 15 feet away and like to work in
the basement so not tearing up the AC line is a priority.  People will have
to decide for themselves there.  The parts in these filters are not that
expensive but by the time they get all the safety labels on them and pay
all they lawyer's when one smokes...  it adds up.

Hopefully Marc's electrodes will get here tomorrow and I can start doing
some hot testing. :-)))

BTW - the local Qwest Internet connection to me, hot-streamer, and probably
Chip's computers have been real bad today.  If you can't get through or
something seems real slow, it is...

Cheers,

	Terry




At 10:46 PM 8/4/2001 -0400, you wrote:
>Terry,
>Way cool!
>I tried a GMHEI coil today and it actually seemed to give a smoother
>trigger, The safety gaps only fired once or twice as opposed to every
>ten -twenty seconds with the ford coil. Not sure if this was the reason,
>but i switched back and forth between them and the difference was
>consistent. 
>I rf grounded the core and gobbed some hot glue around the primary leads
>at there base (Just for security).
>I just hot glued a flat headed brass 1/4" x 20 screw into the hv
>terminal for hv tap. I mounted the GM on four nylon screws for stand
>off's.
>Definitely looks more HV tech'ish then the ford can?
>Great work!
>Marc M.
>
>(I'm practicing my SHIFT key(place smiley thingy here))
>