In May of 1997, Wild Bill Emery, Bill Luck, and myself (Bert Pool) traveled down to Austin, Texas, to see Greg Leyh's big Tesla coil. SRL (Survival Research Laboratories) put on one of their bizarre shows, and we knew Greg would be there with his big DC coil. Greg has built a large (42- inch diameter, 14 foot tall) coil wound with 8-gauge wire. It is powered by a 30-kilowatt DC power supply. The primary is a 300 pound mass of copper strap making up about four turns. The toroid is about 6 feet in diameter with about a 12-inch cross section, and is made up of an open framework of aluminum tubing. His coil makes 21-foot sparks, though Greg says he can rewire the power supply to make 30 foot plus sparks! He's currently (fall of '97) working on a coil capable of 44 foot long sparks.


[26k] Looking up at Greg Leyh's monster DC powered coil. That coil is about 14 feet long!

[22k] Bill Luck taking photos of large coil.

[29k] Greg returning from starting 100 KW generator which powers coil.

[26k] Greg and Wild Bill standing next to coil, showing scale of primary and secondary.

[13k] [14k] Two shots of Greg's massive rotary gap.

[22k] Close up of beveled, 1-inch diameter tungsten-rod rotary gap. The triangular electrode mounts on the rotating disk.

[21k] Close-up of the three-phase power transformer which supplies approximately 24KV DC (after rectification) to the coil.

[21k] Close-up of one of the half-dozen or so impulse capacitors.

[22k] One row of impulse caps.

[24k] Greg and Wild Bill examining primary construction.

[32k] Note the beautiful construction of the heavy copper primary. This baby is designed for current!

[23k] Fast recovery diodes in oil. These hockey-puck diodes would cost you at least a couple hundred bucks each, if you could ever find a source for them.

[32k] Secondary is space wound with 8-gauge wire. This is a BIG coil.

[30k] Power controller cabinet.

[31k] Greg Leyh, himself.

[31k] Greg Leyh, Bert Pool, Wild Bill Emery, unidentified SRL participant.

[20k] Sparks hitting robot.

[22k] More sparks during show.

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