A client, who is a hairdresser and also does manicure, had an "oven" with a 4 W UV fluorecent lamp (a normal fl. lamp minus phosphor) that didn't work, so I took out the old (chinese!) circuit which was made of resistors and caps, and put a 4 W ballast plus starter and works ever since. The chinese of course are too cheap to put a real ballast and starter (the steel and copper are expensive) so they substitute it with a circuit that's cheaper. I also tried to repair a el-cheapo torch that had a lead battery, with a built-in charger, touched the terminals of the battery and got the nastiest schock of my life! they didn't use a regular 12 V transformer, but a minimal circuit with a capacitor and a resistor! When a battery was connected the voltage was dropped to 12 V, but on open circuit it was 600 volts!!! It's a miracle I lived to tell the tale!