67 tach send out? Or can i fix?

Hellooooo FABO!!
1967 barracuda tach. Sold as "working". Not so much. Hooked up a spare tach to original slant six car to make sure i had a good signal to duplicate (has a coil/factory type setup. Then tested this tach in the same manner.

The barracuda (the car this will end up in) has holley coil/ign box at this point which might be a factor.

I am under the impression that 67 was one year for some components and this tach runs off 12V???

So i have to question my testing methods.

What would FABO do?

Thanks in advance. (I hope you feel special that i took the time to spell that out.....old school)


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