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Jul 4, 2012
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Olmsted Falls, Ohio
The simplest ignition I can come up with besides points.
Just a quick update on the LS1 smart coil and driver board. I tested the coil a bit more and the required driver components. It will work with just a Hall-effect but it's not consistent. To correct this a PNP transistor is needed to drive the spark signal. The signal drives a transistor inside the coil so more current is needed. I went to a 1K ohm pullup resistor and I don't want to go below that because the Hall-effect or most of them can only handle 20ma of current. I could go down to 600ohms for 20ma. I did notice that just like older GM designs it needs to see a positive going pulse to trigger. The board is 17mm wide and 26mm long. C1 should be 0.01uf to 0.1uf ceramic depending on Hall-effect used. In the setup below the coil will fire after the magnet passes the Hall-effect or when the LED turns off. No dwell control or limiting resistors are needed because the coil handles all that. Just add a Hall-effect, 12 volt supply, and a LS1 smart coil. You don't have to use the 2N4403 (PNP), you can use something similar. I used it because I had them.

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I included a pdf below that can be used to turn a CD disk into a timing wheel. I have others to share with timing events. If there is enough interest I'll get extra boards made. Oh I also cleaned up the board design a bit, things like better pours and changed Q1 to a wide T092 pad.

Did you ever get anymore boards made? I'd be interested. Dave

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