 Spark Gap Tesla Coil operated from 220/240V mains without a transformer  Tesla wrote in his early lectures that he was able to sustain a spark gap with as little as 200 volts. Here's proof.  This gap was adjusted from .0015" - .0005". A simple choke coil was placed in the circuit to limit the current from the 220/240V mains. A .15 mfd condenser wsa placed in parallel with a spark gap in series with the Tesla Coil. A normal circuit only without a transformer.  Sparks were not long (.75" - 1.5") but were extremely hot. Equivalent spark of a diathermy machine yet only 240V 1000mA input power. Click here for a movie!  Output was seen as a thin straight spark surrounded by fiery flames that radiated a lot of heat.  At maximum spark distance the spark tends to form a ribbon of sparks / flames.  Single Bovie Spark Gap and Electromagnet / .15 MFD Condenser     5" Pancake Coil - 1000T Silk Covered Secondary (32 AWG) and 6T (10 AWG) Primary A 240V spark gap driven Tesla Coil is not impossible, but requires a precision tungsten spark gap. However, by increasing the voltage to only 300 - 750V much easier results are obtained and a normal spark gap is more easily sustained. It is also curious to note that a .5 mfd condenser can be used and a normal "model T" ignition coil replaced with the Tesla Coil. The whole coil must be submerged in oil and an amazing 2" flaming discharge will result. Photos tommorrow! |