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I have been chasing what should be a simple reset problem with this Universal slot board for a week now. This is the first slot board I have had to dig so far into and obviously I am missing something.
The reset line (pin 26 of the CPU chip) remains low. As far as I can figure out ECN-2 pin 5-E is where zero cross comes in and is converted to a square wave by Q1 then IC 4F. This square wave prevents C14 on the 555 timer (2G) from putting a high on pin 5 of IC 4F and making the reset line go low. Q1 was shorted so I had no ZC pulse so I replaced that and the three tantalum capacitors near it.

This problem was aggravated by a brand new nicd battery that would not hold a charge and only putting 1V on Vcc of the RAM chip. Fixed that, replaced the battery. The previous battery had leaked so I had 5 traces to repair and ended up replacing the EPROM sockets, the CPU socket and the RAM socket.

I can now see  a good square wave on the cathode of D66 but the time delay of C14 charging then turning off the low reset line never happens. The circuit remains in reset. I replaced IC's 4F, 3G, 2G, 5E and 8D (all in sockets now) and the reset line still remains low. I can trick the circuit by manually pulling the reset line high by raising pin 5 of 4F out of it's socket and connecting it to ground. The CPU fires up and starts talking to the EPROM's when I do this but start up sequence confusion prevents me from obtaining "game".

What am I missing that is preventing this circuit from working. I have Ohm-ed out the entire reset circuit and related components and verified that all traces are intact and there are no unrelated shorts. All EPROM's and the CPU chip work in a known good board.