Tachometer signal on my 76 coupe

[Nigel curry]

Hi all, I thought I’d post this problem before I drive poor Gavin nuts,I can’t seem to get my tachometer to read engine revs increase at all,after installing new circuit board and zeroing it in as per instructions when I fit the three pin plug it zeros in perfectly but refuses to move when I press the accelerator.I have power from the red feed in and the black earth is good,I also get a light from the signal (brown signal cable)I have even tried another tachometer lent to me by Gavin but I still get the same results.i am awaiting another board from Gavin and I will try that(hoping that the new board is somehow faulty)unfortunately I don’t have the gear to test the signal pulses or any knowledge on the item that sends the signal from the distributor there is no inline filter on the signal (brown cable)but I have been advised that the tachometer should still move when revs increase and previous owner never got to fix the tachometer so could offer little info

Any ideas/ advice greatly appreciated Nige

 

[Nigel curry]

Hi all
Just a foot note to the tachometer problem it was indeed a faulty tach board so once again problem solved thanks to Gavin thanks again.
Nige