Quoted from JethroP:Probing around to measure this I discovered a poor connection the IC chip pin in the machined socket.
I presume it was the U10 pin in question? Is the repair going to last longer term?
Quoted from JethroP:In the switch test, #14 still shows up (the only switch to show up) as closed in the game reset condition. I moved all the dip switches to off and still #14 shows closed in the test. I know it is unused switch, so does this matter? Should it be tracked down and fixed, or is this ok?
Does removing one/both of J2/J3 from the MPU board resolve this? The concern is if it's going to cause some shadow issue in the switch matrix.
Normally I would say yes, but the sockets have already been replaced and there's been some collateral damage to the board. It's too risky.
If you find that you're getting connection issues with these sockets, the best bet might be get some SIP sockets, or 40 pin machined IC sockets to piggy back into the current loose sockets as a new interface for the chips. The diameter of the round pins will be better grabbed in the suspect sockets. It might look odd, but reliable connections are more important.
Every machined socket I install I check each pin receptor one at a time. I don't insert the chips pin all the way, just look for resistance. I often find a socket with one or two loose pin receptors that the chips pin floats around in. The trick is that you can actually push the faulty receptors out of the plastic housing from the bottom up and use a good receptor from a donor socket for this purpose. Tayda actually sells these machined pin receptors separately.
You might want to try this with those 40 pin sockets to see if any/many of the receptors are loose.
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Queen Creek, AZ
