Hi Everyone,

My Global Specialties 6000 frequency counter counter died on me, it
powers up, but does not count.

I wonder if anyone has a manual/schematics and could guide me through
the repair. I looked around and found no documentation available.

The counter itself was made around the '80s, and it uses an LS7031
counter/driver chip, National MM5369 based time base, and a bunch of
CMOS glue logic. The first two digits of the counter are implemented off
the LSI chip for speed, in this case two chips of dual J-K flip-flops,
74S112, and a 74LS90.
The signal gets through the input stage, but the J-K flip-flops are
already not counting.
I would really appreciate if someone could help me out with the
schematics, it would save me reverse engineering the circuit.

Thanks for listening, Peter