[Farmall] Tachometer

[Robert L. Holtzer]

 From time to time there has been discussion of setting engine idle, 
etc.  Recently in a model airplane shop I saw a $25 tachometer that had an 
RPM range of 0 to 30,000.  It detected RPM from the propeller -- apparently 
something akin to a strobe.  It would probably work off a painted mark on a 
crank pulley.

Anyone have any experience with this type of equipment?

Bob Holtzer