- 12-18v in = ~73v+ out
- Uses only 2 transistors, no IC's
- Can be made out of one CFL light bulb
- Uses fully discreet components
- 17.2kHz switching frequency
Output is only low current but could probably be used to power a small triode preamp stage (Very high impedance)
UPDATE: Thanks to "neumanngregor" for pointed out: ONLY USE ELECTROLYTIC CAPACITORS IN SERIES AS A LAST RESORT, I am not responsible to any damage caused. If possible, use properly voltage rated capacitors. Thanks :)
If you are unsure of the the inductor size, just try tweaking the oscillation capacitor until you get the highest voltage :)*
*A general rule, since this is a constant duty cycle, larger inductors will need a lower oscillation speed.
Step 1: Parts and Specs
Most standard transistors should be able to cause an avalanche on 12v but some transistors dont (as I have found out!) I find the BC337 and BC547 to breakdown perfectly.
The circuit oscillates at ~17.2kHz, nearly above the audible range.
The parts required:
TIP122 or Power Darlington transistor
BC337 or Compatible
0.1uF/100nF Ceramic Capacitor
100uF Electrolytic Capacitor (Preferable 16v if the circuit is ran on 12v but 10v should do fine)
Any high voltage capacitor. I used two 63v capacitors in series to double the voltage rating.
Any suitable diode with high enough voltage (1N4001 isn't high enough voltage, its rated at 50v)
An inductor with inductance between 1-5mH should be fine