Posted on Dec 4, 2012 5626
The Tesla coil described here can.generate 25,000 V. So, even though the output current is low, be very careful! The main component is a flyback transformer from a discarded TV. A new primary windin_g is needed. Begin by winding 5 turns of #18 wire on the core. Then, twist a loop in the wire, and finish by winding five more turns. Wrap with electrical tape, but leave the loop exposed. A four-tum winding must be wound over the ten-turn winding that you`ve just finished.
That is done the same way. First wind two turns of# 18 wire, then make a loop, and finish by winding two more turns. Again, wrap the new winding with electrical tape, leaving the loop exposed. When the windings are finished, the two loops shouldn"t be more than 1/.-inch apart, but take care that they do not touch. Connect a 240-U resistor between the two loops. The modified transformer now should look like the one shown. Connect the transformer as shown. The 27 -U resistor and two transistors should be mounted on a heatsink and must be insulated from it. The output of the high-voltage winding should begin to oscillate as soon as the circuit is connected to a 12-V de power supply. Ifit does not, reverse the connections to the base leads of the transistors. In normal operation, you should be able to araw l-inch sparks from the high-voltage lead using an insulated screwdriver.