I'm trying to design a waveform generator for some cold-cathode neon computer lights. I would like this to go from 0 to 1000 or maybe10,000 Hz, and be able to drive four sets of lights in synchronous delay. I'm thinking something like a PIC to drive some 2N3055 transistors I have, and I found a nice 12VDC/30W (from mains) supply. Does anyone have experience with a similar circuit? I looking for possible PIC advice, or an alternative circuit or IC to drive the 2N3055's. If I'm reading the spec right, transition region for these transistors will be around 0 - 0.4v if I'm drawing around 0.5A per set of lights. Do I need some sort of diode to protect the transistors? I need to figure out how to build in a variable resistor or capacitor to provide a knob to adjust frequency. Any help is appreciated!