jondee86 wrote:Actually, looking at the diagrams you posted above (bottom one of the
three), you can probably get the Mitsi igniter to do the switching. So all
you would need is a 12V supply and a small coil. Just don't know if the
voltage spike would upset the transistor ?? Sergei ??
Cheers... jondee86
definitely can. Depending on relay size, the voltage generated on switch off is in range of couple of hundred volts, so something that can handle 300V+ a must have. Since you need that spike to trigger, you cannot put diode across the coil (but you can put 30V zener to clamp it and get by with a normal transistor).
The only suitable I could find from jaycar is this:
http://jaycar.co.nz/productView.asp?ID= ... BCATID=447
or something like this from RS:
http://newzealand.rs-online.com/web/sea ... &R=6639238
You could just modify the tacho to work with 5/12V signal (assuming the tacho in question is electronic and not some weird electro-mechanical)...