Got home Friday night and had a box from Mouser waiting for me.
Saturday morning was time to tackle the daughterboard. Here is the patient. You can see the bad wire on the connector cable.
We can rebuild it. We have the technology. ... Better than it was before. Part of the contents of the Mouser box. The sockets are still relatively cheap, but they are double wipe sockets. Replacing every socket on the board, even though the four 20 pin ones may not really need it. The blue items are the ribbon cable connectors.
With all the chips pulled, you can see the top 24 pin socket is broken in the upper left.
Just a hint for folks rebuilding. The EPROMs were marked with their board location, but the various 20 pin chips weren't, When you take things out, place them in relation to each other as the would appear on the board. Works for screws and bolts too.
I was definitely tired of desoldering by the time I got everything off. It looked like someone had done some "repair" work on the U7 socket (the broken one). I doin't know if they had replaced it, or were trying to desolder it, or what, but there was an excess of old flux and if they had replaced it, their soldering skills left much to be desired. I washed and scrubbed the board to get ride of as much of the old flux as I could.
I installed all the new sockets and tacked them in place, to ensure a good even installation. Also installed the two new electrolytic capacitors.
Soldering all the sockets was way faster than desoldering. Taking them off probably took two hours. Soldering the new ones in place? Maybe fifteen minutes. Twenty if you include washing the board to remove any new flux residue.
Everything re-installed. I should probably break down and get an IDC connector tool. I have two pairs of large pliers that did the job just fine, but left some teeth marks on the plastic. Normally, when I do a project, I'll purchase any tools I need along the way and slowly build up my tool collection. I make cables so rarely that I didn't think it worth it. Kinda wish I had....
So I knew the main board worked as a Pac-Man board. The question is "would my three hours of work bring it to life as a Ms Pac-Man?".
I did find that the Player 1 button didn't respond, but everything else was functional. So now it was time to do some clean up work. I pulled the front glass of and removed the monitor bezel. I didn't take a picture of the monitor before I started, but man was it nasty. A bunch of cleaning later...
So with the monitor clean and the smoked acrylic overlay off, I could see the actual state of the display. It's pretty burned in. I'll have to decide later if I want to spring for a replacement, or convert to an LCD (unlikely).
Cleaned the bezel and smoked acrylic sheet and put it back in place. The acrylic is in fairly decent shape, but will likely get replaced anyway as it is cheap and does have scratches in it. No way you could have 30+ year old acrylic that doesn't have scratches.
The dirt coming of this machine is interesting, to say the least. I don't think it was well stored after it was retired from service and I suspect that it saw service in an establishment that saw a fair amount of smoke. This is the back side on the glass. You can see the bottom where the artwork is peeling up. I couldn't help but end up removing a bit while cleaning. It just flaked off. In the end, I'm going to get a new graphics overlay, and probably a new sheet of glass, so it's not the end of the world. The brown is "dirt". It took several passes to get it all off.
Much cleaner now. If you compare to the previous, you can see the little bit of artwork that I ended up removing.
All back together. You can just see the right hand latch for the control panel at the bottom of the picture.
I didn't take pictures of it, but while I had the control panel off, I cleaned the cobwebs and dust out. One of the leaf switches on the joystick had gotten bent, though was still functional. It got straightened. All the switch contacts got a decent cleaning. That brought Player 1 switch back to life.
With everything cleaned up, you can actually make out what it one screen in normal lighting. It really was that bad.
With that, on to the marquee light, to see what things looked like there. I didn't take much in the way of pictures as it was pretty boring. Remember how I said the cabinet wasn't stored the best? This is the starter for the marquee light.
That is a dirt dauber nest. The cabinet was full of them. That wasn't actually the problem with the light though. The ballast was shot. It was an open circuit when I probed it. I picked up a new electronic ballast and a new set of bi-pin sockets, as well as a 4100k 18" tube. I was actually really lucky in that I didn't even have to drill a new hole in the light fixture to mount the new ballast. Got it all wired up, and clean the marque while I was at it.
The marquee is actually in really good shapre. There are a few scratches in the artwork paint at the very bottom, but you can't really even tell with it installed. Until I get new artwork to compare it against, I can't tell how faded it is, but if the colors are relatively close, I'll probably keep the original marquee.
I replaced both bulbs in the coin door. Out of curiosity, I tried the coin mechanisms. The right hand side worked almost immediately, and after running a few quarters through it to loosen things up, it seemed to be reliable. The left side just seemed to eat quarters. The coin chute showed some denting and deformation. When I took it apart, I found out why it wasn't working. It was jammed with two slugs, a quarter, a nickel, and a penny. So, along with a dime I found earlier, the cost of the cabinet has been reduced to $99.59.
I straightened up the coin chute and put it all back together. Both side now, pretty reliably, accept quarters. If the counter is accurate, this machine has taken over 190k quarters in its lifetime.
So what do I do now that I have a fully function Ma Pac-Man?
Play it, of course!
Today, I picked of a replacement power switch as calling to old one "functional" was a stretch at best. I also have a cord to replace the existing power cord. Someone had broken the ground prong off, probably so they could plug it in to a cheap, two-prong extension cord.
So what now? Well, the monitor needs some TLC. This is a picture take before I cleaned everything, which is why its fuzzy looking.
You can see the non-uniform grid. I expect the monitor would benefit from a cap kit, though I need to consider whether i want to rebuild it, or replace it and get ride of all the burn in...
I also need to pull the main board and re-cap it. It seems reasonably stable, but there is a small bit of hum in the audio. I have all the caps, so I just need the time.
While I was digging around and cleaning, I realized what a find this machine is. It is an original, un-modified, Ms. Pac-Man. The wiring harnesses still have their factory id tags on them. Cabinet no 10371.
So I'll probably re-cap the main board, then take a bit of a break on it as a project since the next step is going to be tearing everything out of the cabinet and starting the paint work.