How to test 71 Cuda Rally Tach

[DocMel]

I cant seem to get my original 71 Cuda Rally Tach to work  I have acces to thge leads directly of the tach   Any way I can I can bench test it?

Footnote;   I cant tell you if it had points ignition origally or not   It did have a MSD nonvacum distributor when I got it

   I put in an aftermarket vacum electronic points distro and am running a stock type coil.   The tach has never worked since I got the car

How can I bench test the tach?  I treid connecting the tach to the pos on the coil, but no joy...

Any suggestions?
ir

[72rtchallenger]

the tac  green with yellow tracer wire connects to the neg. side of the coil,,dont know if u can bench test

[Topcat]

I'm not an electrician, but from what I recall you would need an ocilloscope to re-create the sine wave that the coil generates. That should send that correct pulses that the tachometer is looking for. 

[ShelbyDogg]

Just hook 2 wires to it. The female spade goes to 12v, the post goes to a coils negative. Surely you can alligator clip it to a running car somewhere.