I will keep an eye out for a junked engine with an electronic module
in it. i have been curious about that too.

Dan



Ron Thompson wrote in message I was working on my father-in-law's lawnmower. I replaced the points
and didn't want to do it every year.
I recalled this simple little circuit and got obsessed with finding it
again. Still no luck.
The zener and SCR sounds like it may be the ticket.
Thanks everyone for your responses.

Ron Thompson