Hmm, this sucks, it isn't working. They used this choke:
http://tinyurl.com/593uyv
Radio Shack is now Circuit City here in Quebec (La Source), and that part number doesn't come up on their web site. I used this choke:
http://tinyurl.com/9xzkv2
I didn't think of checking the current rating, they mention measuring "roughly 100mA of peak inductor current". But the part I picked at DigiKey is only rated for 44mA, that probably is not a good thing. The choke I have is about 1/2 the size of an ordinary 1/4 watt resistor, theirs appears the size of a 4.7uF electrolytic capacitor. I have a feeling I need a larger inductor with larger windings.
They discuss theory and a high voltage test. "After a current is allowed to build up in the inductor, the switch is opened." And then they check the voltage on the lead on the GND side, they measured "a 300V peak". If I try that test, my power supply shuts down, as if I shorted the lines, maybe if I put a LED in there to act as a load...
(keep in mind that this is my very first foray into inductors and frequency generators - kinda happy I got the 2 timers generating the exact frequencies on my first day)
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