Monday, February 27, 2012

Tachometer Works!

After finding that the tach wasn't displaying anything after installing the tach sensor unit from RechargeCar, I did some additional research.

The sensor is putting out a 12V signal, but the tach is expecting 100V+ signal from the coils of the gasoline ignition system.  Folks on 914 forums suggested either designing a booster circuit with parts from Radio Shack, or just buying a tach adapter unit by MSD.

This is how it looks out of the package.  The wiring is very simple, with 12V power, ground, tach sensor in and tach output out. 

 I wired it up and it worked first time.