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First light for my first coil today !



Original poster: "Ian McLean" <ianmm-at-optusnet-dot-com.au> 

Hi all,

First light for my first coil, whoa hoa !!!!

Specs:

6x32" secondary, 1163 turns of 0.63mm enamelled copper. Fres ~= 144kHz.
11.5 turns 0.25" Cu pipe pancake primary. 0.5" spacing.
15kV 120mA (2 x 15/60 NST's) Power Supply.  Protection gap and RC filter.
MMC is 1 to 5 strings of 12 CDE 942C20P15K 0.15uF 2000V caps.  Adjustable
for  12.5nF, 25nF, 37.5nF, 50nF, or 62.5nF.
Coupling is adjustable, but currently set at: Primary level with first
winding of secondary.

Lash up:

I had to lash together a few things that were not finished to get a first
light, I just couldn't wait to do a test !

No proper RF ground yet - I have the copper clad grounding rods, just have
to pound them in 6 feet.  Just used an overhead metal beam in my workshop
for RF ground for the first test.

No proper toroid yet - I still have to get the ducting.  For now, using a 2
1/2 inch diameter foam "noodle" (those swimming floaty things), that I found
in my parents garage, rolled into a toroid about 20 inches in diameter,
taped, and covered with aluminium foil - pretty dodgy I know.  Resting about
3 inches above top of secondary form with a wooden plank.  Even dodgier, I
know ;)

No proper static gap yet (going to build a sucker once I get a vaccuum
motor) - and I haven't tried (not game to) my tungsten SRSG yet.  For first
light, I just slapped together a 5 segment 3 inch long copper pipe gap with
two 12V muffin fans blowing on it, basically a very quick and nasty RQ gap.

Did not tune the system either (no point really until I get the proper
toroid and sucker gap together) - just used the JavaTC calculation of 8.5
turns for an LTR cap of 37.5nF for a static gap.  I have 62.5nF at my
disposal, but that is about LTR for the SRSG.

Results:

With all the dodginess above, I didn't expect much - BUT ...

At first power, I got streamers from about 1/2 power input onwards, and I
was getting 3 foot streamers at about 3/4 power input (i can hardly believe
it, but it's true :-) !!!! ), to the nearest metal object - a table vice
sitting on my workshop table, and to the hanging RF ground wire (as I said,
tied to a beam overhead), and lots of 1 or so inch surface crackly streamers
all over the toroid.  The streamers are not very thick yet, quite thin and
wispy.  No arc overs, flash overs, corona, or racing sparks were noted (good
thing).  I was surprised at the hits to the RF ground wire, as this is
GTO-15 cable.  Oh well, I guess that insulation cannot even begin to hold
off TC voltages !!  The gap is VERY loud and VERY bright - sounds like a
machine gun on full-auto.  I turned the power up a bit further, which
triggered the safety gap.  End of first light test.  Did one more quick
power up to show my parents (I currently live with my parents, and they were
curious after I came in with a smug look on my face saying "It's working,
it's working!").  They were suitably impressed (mostly with the noise I
think).

Pretty pleased with that result :)  Once everything is properly completed
and the system tuned, I am expecting pretty good things from this coil :)

More testing tommorrow ;)

Sorry for the long post everyone, I am just so excited about today's success
:)

Rgs
Ian