I picked up an 82 Bally Mr and Mrs Pacman...The board has bad acid damage...I'm not scared of it, but I don't know the value(?) of a crusty capacitor...Can someone with experience point me to what I need? I have no schematic for this machine and the numbers aren't on the part or the board anymore for reference. I'm hoping one of you guys know right away when you see my pics what capacitor I need...Thanks....

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Thanks everyone!! Thanks Kent for the cap. value!!

I'm going to repair it myself(or try). Basically just for some experience and the challenge of it. I have most everything that is heavily corroded. I'm replacing some of the sockets tonight. I gave it a quick bath in baking soda water, a little dremel ,wire brushing here and there. And some fiberglass brushing. Right now I'm doing a quicky to see if I can get the machine to fire up... I plan on going through all the boards later, caps, connectors, etc....

I'll post a few pics of my umm...hack job? as I go!

I may replace it with a better board later, I'm just up for the challenge of making this one work....for now.

Thanks again!!

Here is as far as I got...when the fiberglass brush ran out. So I jumped to fixing some of the sockets for now...

A friend said..."you can't fix that", so now I have to just to prove a point!!! even if it does end up only temp to get the machine working...

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thanks everyone!!

I'm learning a lot so far....I'm back to the rectifier(?) board (-54 board)...My Tp3 is at 22 vlts dc to 48vlts dc depending.... with every thing unplugged except the transformer...I found the schematic online and it says there should be 5 voltsdc there(the writing is a little smudged)? I've done everything I know how!! Both br1 and br2 were removed from the board and checked ok. so far I have had everything removed from the board!!! Cr5-Cr8 were removed and tested good,they are the only things on the board right now and still 21.5 volts dc...What am I doing wrong,missing, or what don't I know? All transformer voltages are good, within a volt or 2 of what they should be..

my next step is to check transformer wires to connectors just to make sure someone hasn't switched them at some point. My jumpers are set for 120 ac, my voltage coming in is 120....

I'm still learning, so I know a little.... but not enough to ...Know!

The voltage coming from the transformer into that section is 14.7 vlts ac, (blue wires).......so that checked ok...

Vr1 is still on the board, do these go bad? Is there a way to test them? Could this be a possible problem? Am I reading schematic wrong! HAHA I'm having a blast so far but this part...where tp3 voltage is high is driving me nuts!! I even ran ground to the board, just grasping for anything, and no change. f3 is the only fuse in it right now. Earlier when the board was together, and all fuses plugged in the voltage jumped to 37 vltsdc, if I put the meter on ac, I get 5 volts ac at TP3.....the schematic says dc.......And HOW!! Am I getting an ac and dc reading from the same test point! I'm using a decent meter, so the meter is good! It's an Ibm made by fluke, I know my basics with that. and how to set it....So, I'm really stumped on this part!

I'm half tempted to remove everything from the board and do it right, but I haven't made it past the rectifier board yet!.....Last night I decided to start at the wall outlet and work my way in checking everything on the way...I got stuck on this tp3 thing and kind of wonder if maybe I'm just reading something wrong... I'm having way too much fun though! I have to fix the mpu when I get back to it! I just have to! Well?, unless I can't!

A few years back a neighbor gave me the meter,logic probe,the tools to take the connector pins apart, amp probes, and bunch of other stuff I have no clue what it is yet. A big box of caps,resistors,ic's,etc..... My dad was into electronic repair so I picked a few things up from him and from places that I've worked at simple fixes. This is fun because I can try to learn a lot more as I go. None of it scares me, just a lot I don't know enough about yet...

I'm back up to the mpu...

Thanks all for the responses..
and you guys were right....It couldn't be just patched quick...But? I had to try!!!

Now!! I pulled everything from the corrosion areas...Pulled pads,through holes, etc... Some of the parts were held in by corrosion, in some areas there wasn't any solder there....So, after burning my fingers almost jamming the soldering iron in my eyes or fore head from slipping off the board..I now have a starting point and a pile of parts!! I sanded and read the guide posted above (real quick)....

I have no clue how im going to fix the pads and through holes yet...I wish I could just order a pile of parts but right now that is not an option. I'll have to use whatever I can find around the house, make jumpers, etc....I'll figure that out when I start putting things back together. Now!!! I'll get some practice soldering for sure!!

Heres a couple pics...I'm still picking at it..I gave it a few baths in vinegar and a water rinse, used a hair dryer to dry it out good. I'm going to try to clean up and reuse what I can.. This isn't the way I'd like to repair, but I have to work with what I have for now..

Also, notice how I kept my parts nice and organized!! This is going to be fun! Like a puzzle!!

I had the board a lot shinier, the last vinegar rinse turned anything with the silver colored coating left dark....

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Thank you!

I have some of the socket strips, I bought a bunch of stuff a while back to work on a high speed project I have. I never got back to it because I wanted to redo the PF right, and get some practice before I paint that one. Luckily some of the parts I bought for that are the same. I also have a huge box of mixed parts from years ago trying to teach myself and plugging things into bread boards,people gave me etc... so I'm going to dig through there. Your right on the pictures!! I can Identify and test most parts, sometimes I have to do some net surfing to figure out what they are. My biggest problem right now is sitting down and figuring out locations, since most of my numbers are off the board. Which is fine it will give me some schematic reading practice. I know some basics but some of it is still foreign to me. Luckily I did take pictures before I took it apart if I have to refer back to them. But for now I want to try to do it the hard way to teach myself more...

This board was basically trash, so I sure can't hurt it too much! It would still be nice if it worked when I was done though!

Thanks for all the great info you put out there!! I was reading a little in a couple of your threads. I repaired pocket watches for a while as a hobby. I'm noticing a lot of the tools come in handy for this stuff too! Small drills,files, punches, etc...I was thinking I could make small rivets on the jewelers lathe but........ I'm not sure I want to put that much time in it! I will read that section of your thread tonight!! Thanks again!!!

wife on the phone with her mom....." Ya, I have no clue what he's doing out there!! He came in and got vinegar, a hairdryer, and took some of my nail polish out to the garage! When I asked him what he was doing? He said, "Hey! What I do in the garage is my business!" If he comes back in and asks me for a skirt? I'm coming to stay with you mom! I don't even want to know whats going on out there! He was mumbling something about Pacman and acid?"

Thank you!!! Now, I can start sorting and laying stuff out!!

Thanks again!!

Added..
WOW!! Thank you!!! I just went and looked!! It is clear, and with a parts list for the resistors. The manual I was looking at was hard to read and said refer to schematic for resistors. It was a pain to try to sort out! This makes it a lot easier, readable, etc...

soldering on this thing is tough! I'll have to read through the soldering thread again...It doesn't help that my iron was probably about 7 bucks and is probably about wore out! You gotta be quick! Or it all flows to the other side. Like a slinky!! It takes just the right amount of time.....So, I need to go back and read a little more....At least now I have an idea of what happens. The thread will sink in a little more this time..

Thanks again, that print saved my rear!!! In case anyone is trying to use that to locate parts on their board . Above tp2 is a spot on my board for a diode. That print saved my A$$ A lot of time!!!!!! And is a huge help!!.............. Are different on my board from the above drawing and the schematic found on the Pinball data base for Mr. and Mrs. pac man. I haven't figured that one out yet and left them for now,I'll try to understand that later. Maybe a chip change? I also had a lower resistance resistor off of the 555. I put a closer to correct one in and found a new 555.No clue why that was done, maybe to compensate for bad or corroded parts, to get the voltage at the 555 higher? I'll start fresh with that. Those are things I found so far. I'm still working on it here and there. I'll post a few pics of my mess, whether it works or not when I get a little closer to finished. I have decoding resistors down! After getting the multipliers wrong a few times and soldering the wrong ones in. I'm glad I caught that I was doing that wrong part way through. I'm on the caps now.

I figured someone would get a laugh out of my stupidity while working on this board.....

I've had parts in and out, soldered un-soldered, jumpers every where then decided to try to fix the traces etc.. so basically? I think I'm making a mess! To give you a kind of a picture, I'm sitting in the corner of the garage, folding table and chair set up with a lap top, boxes of misc parts and junk, The machine beside the table, basic tools etc....

I'm trying to fix the traces. I was unsure of how sensitive everything really was to static. So, my "great plan" was to plug the machine in since all my grounds are good in that and run a jumper from the ground in the machine to my little folding table, then a jumper to a spiral notebook laying on top of the table. I touch one of those before I handle any Ic's. Have no clue if that is what you are supposed to do or not. But hey? What can it hurt? I'm trying to check the continuity in the traces. They seem to be all connected? I pick the board up look and look, try again, same thing! What the h### is going on? I look again, everything looks ok, how can they all be connected?

Ya,....Well, when I was checking for continuity? I was laying the board on the spiral notebook!!!! I felt like such the biggest Dumb A$$!!! I never like to admit to mistakes, but I figured someone would get a laugh out of it!

I start these threads, then I forget about them or never make it back too them.(can't find them )

What a learning experience!!! I've had this board apart about 4 times in some area's. I replaced pretty much everything on the board. I learned how much? I really didn't know!

I thought I knew electronics? Nope! Not really! I'm learning though...Slowly!
I thought I knew how to solder? Nope! Not at all! Still learning there too!
Plug the Rom in backwards? The little window will glow! Cool!! Yep! I did that on U2. Can I blame it on beer?
Couldn't find anything to cut the flux, so I tried acetone! It took the color band off of my cheap resistors..

The board probably didn't need every part new, but I did it for the experience and to kind of play around. Through PM help from another member that walked me through this, and the board now works! Thank YOU!

It's rough, not pretty! But it works. My pics aren't the greatest, but here's the board all patched up! Will it last? no clue!

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You may be right! I haven't played it yet! Some of this, isn't about the actual game play.It's memory lane, a Classic! Some of us grew up when Pac-man ,Donkey Kong, frogger,etc.... where the newest games out! Or like me, I caught the tail end of it. It was a lot better than playing pong on the TRS-80! Trying to get the cassette recorder to load the game!!!! OHHHH GEEZZZ I'm old!The round Pacman "hologram" in the sticker book, or Trapper Keeper rules!!! Pac-man ANYTHING is the best!

Some of you guys just don't understand! "Pacmans a turd!" dang.....Those are meet someone at the swingset at recess, words right there! Ok I'm going to go listen to some Megadeth or Slayer just to calm down now!

No, I'm just messing around anyhow! You weren't really that harsh. It gets boring in the garage at times!