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First Trial of my TC

Original poster: "Medina, Benjamin (UMR-Student)" <bamxbb@xxxxxxx>

Hello folks. Well, I finished the wiring of my TC today and started the
tuning phase. Using a static gap (temporarily donated by Scot D "aka"
bunnikiller), we first set the # of gaps to 2. By adjusting the knob on
the variac I got to the point where the gap just fires (with the cap &
primary disconnected). We then turned the power OFF and hooked the cap &
primary back to the circuit. Turned ON the power and had a grounded pole
right next to the toroid. At that moment we got some sparks, so by
tapping at different turns and moving the pole away further and further
each time, we obtained that the tap turn was between the 10th and 11th
turn. (Each time we changed the "tap", we turned the power OFF).

We then set the # of gaps to 6, and repeated the process. Then to 8, and
repeated the process. At this point we got around 8" sparks. Each time
we increased the # of gaps, the noise got louder and louder. There were
some students coming into the lab that were curious to know what was
going on, and they got to see the sparks.

We then set the # of gaps to 10, and set the variac to a level where the
gaps just fire. Once we hooked up the rest of the ckt, and turned the
power ON, we noticed that it was arcing in the capacitor bank. So I
immediately turned it off. I thought maybe one of my MMC (bought from
Terry Fritz) had burned or exploded, b/c the sound/noise level was HIGH.
I am thinking of changing the mounting design of my caps. In other
words, rather than having them in a pc board in series as shown below:
  1   	2		3	4
-------  --------   --------  --------  |
  8		7	    6		  5	    |
-------  --------  --------- 	---------
|  9 			14		15
------- ......  --------  ---------

I am thinking about having the capacitors in a straight line to have a
larger voltage differential (like shown below):

  1     2      3     4     5     6     ....    14       15
----- ------ ----- ------ ----- ----- ....... ------  -------

I took some pictures of the sparks and we also got a video, so I will
try to send that out ASAP!!!

There is still work to be done. I am want to try to optimize the
performance of my TC before the end of this semester. I am thinking

1. Adjusting the spacing between each gap and running the tuning/testing
phase again.

2. Possibly finding pie pans with a larger diameter (larger toroid).

3. Having shorter wires on my wiring. As of now I am using neon sign
wire from my NST to spark gap and 12 AWG from spark gap to capacitor to
primary. I am using 16 AWG for the RF Ground (large metal dog cage). But
since we haven't built the casing (wood deck where plywood base will
rest upon), the wire length is a little long.

4. Maybe trying our original idea, the Asynchronous Rotary Spark Gap

I did notice when running with 6 and 8 gaps, the sparks were coming out MAINLY from one spot on toroid (where the ends are taped together with aluminum foil tape). We hooked up a piece of aluminum foil to the top bolt and we saw sparks coming out of the ends of this piece of aluminum foil.

I was so excited yet cautious not to get too overexcited and burn my
components. Today has been a GREAT DAY!!! I FINALLY SAW SOME LIVE

Thanks to everyone on this list that has helped/advised/suggested info
on how to construct a coil based from their experiences.

Thanks again. Regards,

Ben Medina
Rolla, MO.