Quantsuff sent me a link to a Youtube video about Electrofishing. He said “Googling on Electrofishing yielded these numbers: 150-300V, 1-4A @ 16pps (15% duty).” Looks like it might be fun to build one of those gadgets.
I got a Google Alert this morning about a Joule Thief, if you want to call it that, using a Radio Shack 120VAC to 12.6VCT secondary (as the primary), and he was driving it with a 2N3055. He shows the waveforms on the ‘scope. The frequency was down to 47Hz, so it seems like this should work even lower with a little adjustment. It was putting out pulses at a couple hundred V P-P, and input current varied, but at 12V it was about a quarter of an amp. The lamp lit up fairly bright. The main point is that the transformer is available at Rat Shack for a reasonable price, and it seems to be capable of doing the job. But just make sure you put a neon lamp across the 2N3055 to protect it against overvoltage, in case the output goes open (like when the probe’s out of the water).
I was thinking that the 555 timer chip could be used to gate the voltage booster at the 16 PPS rate, or two 555 chips (or one 556 chip) could be used to both gate the voltage booster, and drive the 2N3055 with the correct frequency pulses.