I've moved this from the Tech forum. I'm redoing a SS dash with a Reproduction tach. Its an HEI system. My tach wire is connected to the Tach terminal right next to the B+ in my distributor, and i've got power all the way up to my circut board when tested at the circit board. But i'm not getting any signal in my tach. I just bought the tach from OPGI so I don't think it is bad. I know the old tachs worked off a point system, and my distributor isn't using points.
What should I do? Is there any way to test the tach? Any sugestions and hlep would be much apreciated.

The tachs work off the coil primary side voltage going up and down as the plugs fire. The HEI voltage peaks a little higher than the points but that shouldn't affect the operation. Can you jumper the tach lead around the circuit board to eliminate the circuit board or possibly pull the tach out and wire it up to see if it works? Do you have a good ground to the tach?