After the current runs through the opto isolator, can I run it into a capacitor and then a voltage regulator to power Arduino? If so what size capacitor should I use and how should that circuit be constructed?
Lefty,I'd like use the current produced by the primary side of the coil for two things.1. A trigger to count RPMs (working). 2. Can I use a capacitor to clean up the current and power the Arduino?
Just guessing that the small engine has a magnet mounted on the rotor and every turn it comes close to an inductor coil it induces voltage spikes on the coil to fire the pistons. Could that be right for small engines like lawn mowers? I speak of engines but I have no practical experiences though.
Maybe the way to do this is to add some sort of battery and charging circuit, have the engine charge the battery and have the Arduino just pull its power from the battery. Hopefully that would smooth things out.
The spark is produce when the voltage is high enought to conduct ( die-electric of air ) between the two piece of metal of the plug. A bit like a capacitor when you apply a high voltage ( over the voltage capacity ) and the result is "POOF". The capacitor started conducting.