This is not uploaded yet. Sorry for the inconvenience. The DRSSTC coil section, however, is open.

Here's a movie of the coil running: LINK

Here's a closeup of the streamers: LINK

 

This coil, was my first large scale coil. If going by Peter's definition, "a tesla coil is defined by it's secondary" then this has really been three coils.

It started out running on an NST, but that died because I didn't know what I was doing and then backed the spark gap out too far. Also, performance was terrible, due to the lack of attention to detail, as well as lack of knowledge. The NST repaired, but after learning I could only get about 18" with it anyway, I looked for something a little more robust and powerful. Unfortunately, I don't have any pictures of this coil because of my wariness about digital equipment in the vicinity of a tesla coil.

So, it turned into a MOT coil. At first, I only had two MOT's and I tried the "doubler" setup several times. It worked, but performance was poor (due to power arcing, which I didn't know about) and and diodes in the doubler failed consistently.

After this series of failures, I decided it was time for a bit more investigation. After much research, I realized that my secondary was all wrong (477 turns, 22ga wire), my wires were too thin, my bottle capacitor bank was too big for my NST but too small for my MOTs. So, I re-designed my coil extensively and waited until I got all the necessary parts.

It seemed like forever until I got enough microwaves, (I wanted 7, needed at least 5) and I combed the roads each weekend looking for just the right beer bottles. I found that the 40oz Budweiser bottles made the biggest bang per footprint. ( I didn't care about height.) Back then, I didn't have a great job, and had to save up to buy the wire and the refridgerator tubing. I used old cabinents relatives were throwing out for the base.

FINALLY, I got everything together, and had assembled the coil with much care, but I was still waiting on my 30AWG wire! So, while biding my time, I turned to taking apart some broken monitors I had scored at the dump. I got to looking at the degauss coil and realized it had 30 guage wire in it!!! Hastily, I weighed it and realized I didn't have enough wire to make a full secondary, but was itching to know if it would do something. I also thought that I might learn something before building my permanent coil. I didn't have another PVC tube of good size, so I wrapped it on a 1 1/2" piece until I ran out. I wound up with about 1370 turns.

..........

The "Waiting on the Mailman" coil. So called because I had already waited several weeks for my wire, and so I made a temporary secondary out of a deguass coil from a TV.

I fired it up, and it worked!!!!!!!! Eventually I got 15" with it... at between 1500W-2000W. :) Ok, Ok, I know that's about the most terrible effieciency you've ever heard of, but I didn't care. BTW, I was power arcing and my toroid was waaaay too high. That was my problem.

Then, after the success of that secondary, I decided to try the old secondary with the new power plant just to see what would happen. It fired right up, and I experienced about the same performance, except this secondary had one really neat feature. It (the secondary) glowed! "Wow!" I thought, "That's really cool!" Unfortunately, I didn't realize that wasn't supposed to happen. My coil was on fire from the inside, and quickly became the ruin of that secondary. Opps. Ah, well, it was trash anyway.

My original secondary in the new coil setup. Still waiting on my wire...

WooHoo! I got my wire, and wasted no time assemblying the secondary coil, some of the guys suggested that I should make my primary spacing smaller, so I did. Here's the new secondary with the new primary.

After dealing with power arcing for quite some time, I decided that ASRG was the only way I could curb it. I bought a grinder from harbor freight, and made a rotor out of formica. I chose formica because I already had a bunch, and it was ideal because of it's high temperature properties. Also, it's darn hard to tear up, while acrylic compounds can shatter. The grinder died, and so I took it back to HF for replacement. After installing the new one, it died too. I realized it was from a primary strike, that shorted the windings in the motors coils. BTW, after disassembling the grinder, I would not recommend the cheapo from HF because it is very poorly built, but then again I'm not sure how you can sell a grinder for ten dollars anyway. Lacking the funds to buy a new grinder, I went back "to the old drawing board." I installed a strike rail (I cut the rim off a dryer drum, it fit perfectly.

So, I thought I'd try a blown gap next. I plugged in the coil and sadly, experienced poor performance....Hmm...I looked down at the coil, and realized that I had stepped on the air hose and pulled the air off the gap. I bent down to pick it up and HOLY SMOKES!!! *scrambles backwards* I'd been bending down a few feet away from the coil, and the streamers just erupted! Scared the pants off of me to tell the truth! Adding a bowl on top increased performance, so I started making a new toroid.

This baby's starting to cook!!! Woot!

Well, I'd like to tell you it was all easy from there. I was getting 36" easily, but as soon as I got two more MOT's I upgraded to a 6 MOT coil. Consequently, I got a huge increase in performance, but also I spent days chasing out the new bugs. I had to put everything under oil, after that, everything else was arcing to each other due to insulation problems. First it was the primary wires arcing to the chassis, then it started arcing to the strike rail, then from the primary coil to the strike rail, finally from the primary to the secondary, which was over an inch away! I added more capacitance, and toroid, and got the power arcing under control to the point that the air pressure on the blower gap was minimal, blowing on it with my mouth would equate. After that, though it was all green beans and gravy! I wound up getting 52"! I have backed off a little as that causes high stress on certain components and I can get 48" consistently (which is about 1,200,000 Volts).

Here she is pulling 40 inchers:

I love the corona rings on the bottle caps. They're really cool up close.

And now, 44-52"! (Veteran's Day 2005)

My longest spark. I tell everybody it was 52", but upon referring to my notes, it was actually 50". So sorry if I've misled anyone. 50,000V doesn't matter too much when you're already pumping out about 1.3 Million! :)

A light bulb at atop the toroid adds a nice flair.

 

Looks like one of the bottle caps had a little too much! Man was that loud! (Check out the 3/4" hole in the glass just above the aluminum foil.)