Fostex E-2 E16 count sensor 8251129 100 or 000

This is the count sensor pcb with molex lead from a Fostex E-2 recorder

I have another one from a very early B16 with 000 ending.

I have had a few of these fail, although and yes it sounds stupid make sure you have the timing roller with the  lines on the back on this side people put them back to front and say their counter is duff :-)