As i ve said before, in this second part i will show you my high voltage experiment using my own hand-wound homemade flyback transformer using the ferrite core from the original flyback transformer salvaged from old cathode ray tube (CRT) television monitor.
Before I move on, here are the photos taken and descriptions:
before, except that for R3 i use 500 ohm, R1 at 3kOhm, and 10k potentiometer for R2 for easily varying the operating frequency ( pin 7 of 555 is connected to swiper, pin 8 to one of the end pin while the other end pin is left unconnected, so this potentiometer is modified into varistor rather than potential divider). Also to protect the mosfet i ve put a snubber diode 1N4148 in series with 464kOhm resistor, across the primary winding of the transformer, between the supply line and the mosfet's drain pin.
And it really works...
See ya next time.
p/s: after several times using the power supply, the 555 chip was damaged and i have to replace with new one. This maybe due to high current surge since i m using 3.16 A. Therefore I recommend you to put resistor (for example 500 ohm) between the supply line and any direct input from the supply into the 555 ( pin 4 and 8). To date, i connect pin 4 and 8 together, and link the node to the supply with a 500 ohm resistor. Though the spark becomes shorter, this method may prolong the 555 lifespan and u may still have fun with the spark.