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^^(my) First Light ^^



Original poster: "Matt S. by way of Terry Fritz <twftesla-at-qwest-dot-net>" <matt777777-at-hotmail-dot-com>

Hi,
(questions at end :-) )
So, .... I finally got my coil to a point where I could consider firing it 
up.    I set it up on the porch, and realized that my (manly) hookup cable 
was too large for the connectors I had on hand.
With my wife and kids already (sort of) anticipating the event, (even though 
I told them I had a low confidence level of success), I decided to hook up 
the tank components with ... ..... those little Radio Shack alligator clip 
leads.... no PVC tubing.

My coil specs:
12kv/60ma NST...
4.25" secondary, 22 ga, 23.375 inch winding length.
6.26" id primary, .25 tubing, .5" spacing, 15 deg inv. cone
strike rail 22" dia, 2" up from last turn of primary
toroid 4" ducting, 17" total dia.
multi segment static gap (~.2" total spacing)
TF filter
rf ground = 20 feet of #2? welding cable to an 8 ft (well watered)    ground 
rod
and, temporarily, since I didn't get my MMC done, .. a trusty old fair radio 
.01 uf 100kv cap

Anyway, .. it was just getting dark, ... I set the safety gaps, ... hooked 
it up, taped a wad of aluminum (aluminium) foil to the toroid.. and ran 
20-30 volts from the variac.
the gap started making noise...

My 16 yr old son said "Dad, there's something coming out the top".
I was preparing to give him a speech on the power of suggestion when I 
noticed a bunch of 4" "streamers" coming off the foil.

So I yanked off the foil and gradually increased the input voltage to ~ 70V, 
.. and...the safety gap fired and wouldn't stop....

So, .. I opened the s.g. up, .. and did it again, and the same thing 
happened, ... so I started to open it up again and I heard Terry's (email) 
voice in a past post in my head saying "whatever you do, don't open the s.g. 
after setting it (if you want your NST)" (paraphrasing).... .. (s.g. reset 
to just not fire with nothing connected).

After getting a grip, .. I decided to (lose that grip and) just crank the 
variac further (family pressure and all)... and the safety gap (mostly) 
stopped firing, and there were hundreds (I think) of 10 inch streamers 
swirling around the toroid....
and then at120 volts in, and 4 to 6 simultaneous 24" streamers along with a 
bunch of smaller ones at the same time.
All this in a pretty strong breeze.

This breaks a life-long record of never getting anything of any kind working 
on the first (10) attempt(s).
I just picked a tap point on the primary during setup (~7 turns)... and as 
luck had it, .. it was pretty close.... when I moved it from there, the 
streamers decreased (although I was going a turn at a time).

No doubt I am feeling chipper about it all, .. assuming that I can get it 
much better with cap/gap/top/K/tuning adjustments.
Not to mention proper wiring.
Eventually (after 10 minutes on and off-- mostly on) one of the R. Shack 
mini-jumpers blew a hole in it and started a cooking arc across my nicely 
finished primary base, .. but it's a battle scar I can live with.
For the record, the F.R. cap did get a little warm.
And the output decreased considerably after running for a min. or so I'm 
assuming due to the gap having no fan.

So, ... just in case anyone read this far I wanted to say thanks to the 
list... .. no way I could have tortured those multi-colored jumper leads 
without all the help and archives and answers to my dumb questions.
Which I have a few more of :-)

1. Any ideas on what happened that allowed my wildly firing safety gap to 
stop firing by cranking up the voltage more?

2. I know I've read this somewhere, but when the S. gap fires a lot, is it 
tuning or over coupling?

3. I'm assuming from the many streamers that my topload is too small?

4. 22 gage wiring from the cap to gap to primary and it worked? what tha?

5. In addition to a "Power on LED" I put a silly little green LED on my 
control cab. in parallel with the voltage meter..  .. thought it would give 
me some reference point in the dark. .. it lights at 70 volts.  With the 
coil running, it would flicker at much lower input voltage to the coil..... 
I have two corcom filters in between, but does this mean some V spikes are 
coming back, or does a variac output voltage fluctuate a little when its 
load fluctuates?

Thanks again for all the help.  I have never seen a coil run before .. . and 
.. well. .. there's nothing I've seen that comes close.  (and my wife liked 
it and temporarily forgot about all the $$ and time spent on it)(and my kids 
made the same sounds that they do when watching fireworks)(ok, and my dog, 
who was confined inside, had a spaz attack and tried to dig a hole in the 
hardwood floor to hid in, but 3 out of 4).

Matt.
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