My original little farm of NSTs. It consisted of one 15/30 and two 15/60s. I've had been using two 15/60 NSTs paralleled, until I killed one of them. In order to parallel them they must be in phase.

My friend Justin brought over a modified 12kv NST. It had a short circuit current of 600ma! We just refered to it as a 12/300+. :-) We were using that when I set my first little 2.5 inch secondary on fire. For some reason pushing almost 4kVA through it wasn't a good thing. :-(

The 12/300+ developed a severe arcing problem and has died too. I really should get a pole-mount distribution transformer, aka pole pig, I guess. Eventually I will need to depot and repair my little stack of dead NSTs


Until a pig is obtained, I have discovered the value of MOTs. It started by playing with a 4 pack of them and being very impressed with the results. Here are some preliminary pictures of the 4 pack MOT supply in action. These were running unballasted on my Tesla dedicated 240V 50A circuit. I didn't measure the current, but I know they were drawing at least 30A. Though I really don't have enough tank capacity to run these properly, with 40nF of MMC and a spark gap spacing of .15" I'm was getting 4' large, thick power arcs from my 4" coil. :-)


After messing with a couple redesigns of the 4 pack MOT supply, I decided to build a 6 pack MOT supply. These are a couple shots during the building process. The 6 transformers are mounted to a PE cutting board from Walmart. Then the transformer assembly went into a transformer oil bath inside a Sterilite 38Qt./36L container. I still haven't decided on how to ballast this supply, but most likely it'll end up being a capacitive ballast. Here is a diagram of the wiring (I forget the coiler that originally made this so my apologies for lack of his name in credit). Click here for some pictures of the 6 MOT supply during construction

I recently came across an Amana Radar Range in a neighbor's trash while out "recycling".

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