: i want to generate 25 kv.....to....100 kv...variable....using diac and
: can somebody give me detailed diagram...on my emaikl address.......
: ketan vaidya
There's no simple way to make the output voltage smoothly variable over that range using just diacs and triacs. However, you could use the "Simple High Voltage Generator" circuit below to generate HV pulses that are in the 25 - 100 kV range:
The ignition coil should be an oil-immersed or resin-impregnated "high performance" racing type ignition coil, such as an Accel Super Coil, a GM HEI coil, or similar. Standard ignition coils will tend to flash over or internally short circuit at 75 - 100 kV levels. You may also need to immerse the entire coil under oil to prevent external flashovers when running at 100 kV levels.
By using various AC film capacitors in series with the ignition coil and driving from 120 or 240 volt sources, peak voltages of 25 - 100 kV can easily be obtained. The larger the capacitor, the higher the peak output voltage from the coil. Coil output will be in the form of high voltage pulses that occur at twice the incoming power mains frequency (typically 100 or 120 times/second).
BTW, be VERY careful around these circuits - the high energy output pulses are quite dangerous and can even be fatal.