Re: Gerry's coil pictures

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 

Thankyou Tom,

A friend of mine took the photos with a 6Mpix camera and I don't think he
did any post processing.    I sent them the way I got them and didn't even
think about that.

The coil is 8x36 on an acrylic former wound with 1440 turns of 23gauge
single build formvar.  Prewinding coat on the sanded former is shellac and
there are 6 post winding coats of polyurythene.  I did not sand the inner of
the former.  The topload is a 6x24 toroid by D&M (they did a great job) and
is mounted on an acrylic tube that slides into another acrylic tube
(friction fit) so the toroid can easily be raised (lowest position in the
picture).  The tube is placed in a hole in the bulkhead capping the former.
There is another solid bulkhead of acrylic about 5 inches down from the top
of the former for this tube to rest upon.

The primary uses 1/4 inch CU pipe with 1/4 inch space and is designed to be
raised or lowered 1 inch from the bottom turn of the secondary.  The strike
rail is at a fixed height and with the primary at its lowest (and current)
position, sits 3 inches above the primary.  I haven't yet adjusted the
primary height for k optimization.  Currently there are 20 turns max and
tapped at 20.  Cp is 16.7nf (2 strings of 14 - 0.068uf and 1 string of 14 -
0.1uf CDE caps).  I'm using a static gap made of 1/2x3 inch pipes and 9 gaps
of 35mil each.  Safety gap is set to just not fire with Variac at 140vac. I
have two 100 cfm fans blowing directly down onto the gap (like a Terry gap
where segments are epoxied onto an acylic piece).  During operation, the
safety gap seldom fires and the main gaps barily get warm.

Power is two 15/30's in parallel with the Terry filter physically placed
right between the two.  The NST's are grounded to RF ground (stake in the
ground) and not connected to mains ground.  On the back porch, I'm plugged
into a 20 amp line with GFI circuit breaker and so far it pops only once per
run; it has always randomly popped even with little load so I do think the
circuit breaker has always been weak.  I'm currently not using PFC nor a
line filter.

Next, I plan to switch to SRSG and see how much more power I can draw with
the current power source.  Then I plan to add two more 15x30 NSTs and stand
back :-))

Take care,
Gerry R


 > Original poster: "Tom Luttrell PWRCOM" <tom-at-pwrcom-dot-com.au>
 >
 > Top stuff! That's a good looking coil too, very nicely finished.
 >
 > What were the coil specs?
 >
 > Tom.
 >
 > PS: Taking digital photos is only half the story. Post processing is
 > also required in a majority of cases. The first picture improved
 > dramatically when "Auto-balanced" by Photoshop. I'd show you the results
 > but I can't get to my web space from behind my employer's firewall.
 >
 >  > Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>
 >  >
 >  > Hi All,
 >  >
 >  > Gerry sent me these nice pics of his coil!
 >  >
 >  > Nice night picture of Jerry's coil:
 >  >
 >  > http://hot-streamer-dot-com/temp/48%20Inch%20Streamers.jpg
 >  >
 >  > 59 inch arc with witnesses ;-))
 >  >
 >  > http://hot-streamer-dot-com/temp/59%20Inch%20Power%20Arc.jpg
 >  >
 >  > Gerry with his coil:
 >  >
 >  > http://hot-streamer-dot-com/temp/The%20COIL.jpg
 >  >
 >  > Cheers,
 >  >
 >  > Terry
 >  >
 >  >
 >  >
 >  >
 >
 >