"Roger" wrote in message
...
I am looking for plans to build a Mag timing light with the buzzer that
changes pitch. I remember seeing plans in a Magazine. Maybe Sport Aviation.

Roger @MD43 C150E

This might help
http://www.matronics.com/archive/arc....digest.vol-hx

But since they are relatively cheap ($70), why build one? (unless you have
lots of time on your hands, are handy...)