MCI Computer Baseball

Definitely look for cracked solder joints.

And I would test any suspect transistors before replacing them. On a game like this, you definitely don't want to shotgun parts. Make measurements, find bad parts, THEN replace them. (Measure, Find, Replace.)
 
Definitely good advice. My tester won't do in-circuit testing, so those guys are going to have to come out anyway. Does my thought to start with the transistors make sense? I'm still very much an amateur at things like this. I'm much more comfortable with EM stuff.
 
Definitely good advice. My tester won't do in-circuit testing, so those guys are going to have to come out anyway. Does my thought to start with the transistors make sense? I'm still very much an amateur at things like this. I'm much more comfortable with EM stuff.

If you have a DMM, you can do in-circuit testing.

Most transistors can be tested with the 2-diode test. Google if needed. But most of the time you can tell if a transistor is bad or not without needing to desolder it. (Though in some cases where it might look bad initially, you may have to remove it to confirm that.) But if it looks ok in-circuit, then you usually don't need to remove it.

You want to look for diode drops in both directions (i.e., either TO or FROM the base pin, to the other two terminals, depending on the transistor type.) Then you want to see either 2 or 1 drop in the opposite direction for both terminals.

Out of circuit you'll always see 2 drops to or from the base. But in-circuit you might only see one, if the other things in the circuit are messing up the other one. But that's ok. However a majority of the time when transistors fail, they go short, or open (so you see no drops in either direction), or do other more obvious things.

I would put the visual inspection above all else. Under a bright light. Really scrutinize every joint.
 
So, there's been a development...


I originally spotted and purchased my half-a-copy of Computer Baseball from Bob Cunningham at As Found Arcade Machines. When I purchased it, Bob mentioned that he had sold another, NIB example to a regular customer a while back, that they had in turn gotten from the Time Travel Warehouse in Canada sometime back.

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Anyways, I had reached out to Bob to see if he might be willing to put me in touch with his other customer, in hopes they might be willing to take some pictures of the wiring and components in the lower cabinet. Bob told me his customer and friend Darren Carter, who, incidentally was the founder of Contours Express, a ladies-only gym chain, and had a truly EPIC game collection, had a brain tumor, and wouldn't be able to help. I told him I was very sorry to hear that, and put aside my project for a while in favor of working on some stuff I knew I could fix, and would likely have a place in my game room.

Fast forward to a few weeks ago. I got a message from Bob telling me his friend had passed, and that his widow would likely be selling off his collection, including the new, never played, but no longer in the box, Computer Baseball. I asked him to keep me in the loop.

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Sure enough, it went up for sale today, and now I'm the owner of one and a half MCI Computer Baseball games 🤣

It'll likely be a few weeks before it gets here, and there's no guarantee that one works either, but I'm hoping I can get one, if not two working games out of this situation. Bob told me they had unboxed and assembled the game at Darren's house, and he had wanted his tech to look it over before they plugged it in. So, its still very much a new, never been played game. I ran into a couple of dirty, high resistance pins in the one that I have that caused some minor issues, so it'll get a very thorough going over before I let the angry pixies in through the line cord.

Anyway, I'm pretty jazzed about this development, and the possibility of getting this project back on track!
 
I'm pretty sure that I played this BITD; the more that I look at it, the more familiar it looks. But it's been ~50 years!

Very cool!
 
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