(Topic ID: 46537)

Bally Mystic - Repair - board work

By aobrien5

10 years ago


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  • 40 posts
  • 12 Pinsiders participating
  • Latest reply 10 years ago by barakandl
  • Topic is favorited by 5 Pinsiders

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#1 10 years ago

So, I just got a Bally Mystic that's needs quite a bit of TLC. Got it from a friend who picked it up and didn't have time to work on it. I'm pretty new to all this, but when I look at the boards they look like they're in really rough shape. Apparently, the machine would turn on, but not boot fully or anything. Just enough to get power to some places. Anyway, when I opened it up, I decided there was no way I'd be trying to even turn it on without cleaning it first. Looking at these boards, do they look like they're even in repairable condition?? The MPU board looks mostly clean, but there's some weird bubbling on the back side of it. The Lamp Driver looks like it has battery corrosion or something dripped all over it, and the transformer board is definitely corroded quite a bit. I'm most worried about the MPU/Transformer, as the Lamp Driver board looks basic enough to not be too harmed by the corrosion. What do you guys think? Are these boards FUBAR'ed or just FUBAR'ed for a newb?

MPUboard-back.jpgMPUboard-back.jpg Lightboard-front.jpgLightboard-front.jpg Transboard-back.jpgTransboard-back.jpg Transboard-front.jpgTransboard-front.jpg

#2 10 years ago

The telling sign of the MPU board is going to be on the middle bottom on component side. If there is corrosion, that is where it will be. The picture of the back of your MPU looks fine.

Lamp board looks like someone spilled coke on it. You can clean it with warm water,dish soap, and a tooth brush. Then use rubbing alcohol and fan / hair drier dry. Careful not to bust off the SCRs. Probably fine

Rectifier board does not look too bad. Someone removed wires from the connector and soldered them right to the back of the board. This needs fixed. Install all new header pins and crimp on new female pins. Might need new connector housing if it is burned up.

Check all connectors for busted header pins, look for burnt connectors. Test bridge rectifiers for shorts, test driver board HV section transistors for short. Remove MPU battery if it is there.

I can rebuild your boards if you need help.

#3 10 years ago

Totally repairable! Mystic is a fun game - the spinner sounds are awesome and reused in Frontier. Enjoy!

#4 10 years ago

The MPU (what you showed anyway) and the lamp board look fine, the rectifier board looks pretty beat, and they usually do. There were never any connectors to that one and they are all soldered directly to the wires form the transformer like that. You might be able to fix it, but really, do yourself a favor and blow the money on one of these- http://www.greatplainselectronics.com/proddetail.asp?prod=135-105
It's really a great board at a great price. Re-engineered and ready to go. Only $60.

#5 10 years ago

The MPU board is fine, crinkling/bubbling of the foil is no concern. As Barakandl said, look for corrosion visible as white or green powdery coatings on the copper parts around the battery area on the topside of the board. Corrosion there can be repairable in cases, but usually requires a bit more tech skills.

The lamp driver: Clean as suggested. If what was spilled on it was done when power was not applied you have much better chances of less problems from that. These boards are fairly easy to repair.

The power supply board also fixable. Check online repair docs for some of the reliability mods that may need to be done. Check the fuses to make sure it is fused with the proper rated fuses.

#6 10 years ago

Thanks guys, very very encouraging. I'll get it cleaned up as best I can and see how it goes. I'll take a picture of the other side of the MPU to see what you guys think, but it looked ok, eventhough it still has the battery on it.

That rectifier board sure does look pretty when it's new.

barakandl - thanks a lot of the offer. I'll see how bad it is when I start testing and very well may take you up on it if things get too far over my head.

One more question - some of the connectors were already off when I got the machine, so when I go to plug things back in again is it bad to go the trial/error route with which plug goes where? Will I burn something up if I plug it into the wrong port?

I plan on putting all the wiring in the dishwasher to clean it up. No problems there?

#7 10 years ago

The plugs are all keyed, so it is hard to mix them up. IF you are unsure check the wiring diagram page in the schematics and match up wire colors

#8 10 years ago

* Get that battery cut off! *

#9 10 years ago
Quoted from aobrien5:

I plan on putting all the wiring in the dishwasher to clean it up. No problems there?

I don't advise it, although I think others have done this. Dirt doesn't hurt the wiring, however if any water gets under the insulation and gets trapped - you can get corrosion. I used to wire boats and we had to use a special marine specified wiring. But having said that - the special wire is for constant exposure to moisture on a continual basis. You're talking about basically a one time exposure.
Maybe someone who has actually washed harnesses this way a few times can comment on its pros and cons.

#10 10 years ago

I'm certainly open to an alternative for cleaning the wiring/connectors. Frankly, the whole machine stinks like 30 year old smoke and it would be nice to be able to touch the machine without getting filthy. I figured since I'm pretty much going to be completely disassembling the whole machine, I may as well clean everything I can while I'm at it.

#11 10 years ago

Also, fwiw, this is the guide I'm going to be following to get these boards cleaned up:
http://techniek.flipperwinkel.nl/ballyss/rep/index1.htm

If anyone else has recommended reading, that would be welcome.

#12 10 years ago
Quoted from barakandl:

I can rebuild your boards if you need help.

Take him up on this. If you don't know what you're doing, leave it to a pro.

#13 10 years ago
Quoted from spfxted:

Take him up on this. If you don't know what you're doing, leave it to a pro.

+100

I just did one of his pinwiki upgrades on a -22 driver board. No one better with early Bally. He'll make your boards better than new.

viperrwk

#14 10 years ago
Quoted from aobrien5:

I'm certainly open to an alternative for cleaning the wiring/connectors.

A lot of people put plastic bags around any connectors or switches and then clean with Purple Power (or some other degreaser) and a brush in the bathtub. Of course, that's the kind of stuff that got me divorced.

You could also use 99% alcohol or a board cleaner like MG Chemicals Superwash. Then you don't have to worry about the connectors and switches. Again use a brush.

+3 on not tackling the board work unless you're an experienced solderer and can read a schematic. I would especially recommend leaving replacing things that aren't broken (as some of the guides suggest) to a pro.

#15 10 years ago
Quoted from aobrien5:

I plan on putting all the wiring in the dishwasher to clean it up. No problems there?

Nope. Do it all the time. Just did a MMPM harness. Some people take off the microswitches, others leave them. Personal preference. Make sure it's gentle cycle, no heat, non-sanitary rinse. Hang dry for a few days.

And make sure you do it when the wife isn't around.

viperrwk

#16 10 years ago

Well now you guys are worrying me.

I'm definitely a novice when it comes to board work, but I can read a schematic. My wife is surprisingly tolerant of utilizing the dishwasher/bath tub, but I've been decking out my BSD a little too much lately, so I can't spend a lot of cash on this project just yet.

Here's some more pictures of the MPU, and compared to what I see elsewhere, it looks super clean. There's a little discoloration on the top left corner of the chip in the second picture and the resistor to the left of it. There's an odd looking solder bead, and maybe a missing connector pin in the 3rd pic. Everything else looks surprisingly clean.

MPUfront1.jpgMPUfront1.jpg MPUfront2.jpgMPUfront2.jpg MPUfront3.jpgMPUfront3.jpg

#17 10 years ago

Those boards look pretty good. Get that nasty battery cut off there before it has the potential to cause problems. Off board battery packs or memory capacitors are great options.

#18 10 years ago

Board does look very clean compared to most so that is good. R11 always needs replaced. Yours has a better quality resistor than most, but still replace it. This resistor gets very hot and is too close to the Q5. Bend Q5 or R11 out to give more breathing room.

R113 is also toasty. This resistor and R16 make a voltage divider for the zero crossing circuit. I replace both of these resistors on every board i touch with at a 1/2w 2k resistor. If it goes out of spec too much it can kill U14.

Nothing blocking with windows on your EPROMs should probably be addressed.

The solder beads you see in the 3rd pic is when someone changed rom jumpers. Originally your board had two masked roms. U2 must have failed at some point and EPROMs where used and rom jumpers where changed.

Cut... the... battery... off!!! You are super lucky it has not leaked. Those things are ticking time bomb(that make me money muahaha).

I would say clean up your rectifier board. Get the cat piss off the lamp driver. Check over the driver board. Boot up the game with out MPU j4 connector (and sound board connector). Verify voltages on driver board. If they look good. Hook up MPU j4 and see what you get.

#19 10 years ago

The battery will come off first thing, I promise!!

I did find one transistor on the lamp board that's lifting off the back side, so that needs to be fixed, too. I'll clean them up and see what I can get tested.

Should I just put opaque tape over the EPROMs or what?

I actually found that all the wires on the rectifier are soldered to the PS/Transformer/whatever as well, so I guess connectors should be put on both ends?

I haven't even pulled the solenoid/sound boards yet, so I'll look those over as soon as I get the others cleaned.

#20 10 years ago

Yes, you'll need to pin those connectors. BTW, that "hack" isn't that unusual. I see it all the time.

Yes, tape over the ROM windows.
If you experience unreliable MPU operation, the Sockets on the MPU should be replaced. I always replace them, but I repair boards for a lot of folks, and have desoldered thousands of parts. I'd also burn new ROMs using 2732s but again, that's not for the casual pinhead.

The MCR-106 SCRs on the lamp board often come loose or have fractured solder joints. That's a consequence of being a single sided PCB. No biggie...remove old solder and then resolder. Or just reflow the old stuff, adding a little bit more.

The .100 headers almost always need replacement; again, for reliable operation. The top pins usually have fractured solder joints due to lack of strain relief for the wire harness.

Mystic is a really fun game. It pays to understand the ruleset and how 3 in a row are locked in. We try to fill the board with all pyramids or eyes to hear the triple knocker award.
--
Chris Hibler

#21 10 years ago

Just to be clear, the wires from the transformer to the rectifier board are supposed to be soldered in. What you need to repair are the wires that were removed from the connector and soldered to the board. They need to have contacts crimped on and put back in the connector. You'll probably need new headers also.

#22 10 years ago

ok, thanks. I see it's not in the picture, but the header pins are all fried and some are missing. Seems to be only the input though, all the output still has pins and connectors on the wiring coming off of it.

#23 10 years ago

So I'm getting these first few boards cleaned up and looking at this rectifier board, I don't know if it's worth my time fixing. At what point do you say forget it, and buy a new one? At the very least, this would be good practice for desoldering. It's missing a test point, and I don't know what that black is but it's sure not scrubbing off.

RectFullfront.jpgRectFullfront.jpg RectFullback.jpgRectFullback.jpg

#24 10 years ago

how does your Mystic backglass look?

#25 10 years ago
Quoted from aobrien5:

So I'm getting these first few boards cleaned up and looking at this rectifier board, I don't know if it's worth my time fixing. At what point do you say forget it, and buy a new one? At the very least, this would be good practice for desoldering. It's missing a test point, and I don't know what that black is but it's sure not scrubbing off.

It's salvageable....but it would be a lot of work.
I can tell you that those fuse clips (that need to be replaced) take a LOT of heat to remove as the attached large PCB traces act as heat sinks.

IMHO...you'd be better off just getting one of these...
http://www.greatplainselectronics.com/proddetail.asp?prod=135-105
...my favorite.

It comes with the female housings and pins too.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info

#26 10 years ago
Quoted from ChrisHibler:

It's salvageable....but it would be a lot of work.
I can tell you that those fuse clips (that need to be replaced) take a LOT of heat to remove as the attached large PCB traces act as heat sinks.
IMHO...you'd be better off just getting one of these...
http://www.greatplainselectronics.com/proddetail.asp?prod=135-105
...my favorite.
It comes with the female housings and pins too.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info

+1 When power supply boards have minor issues go for a fix. When they need overhaul and there are readily available replacements it's a no brainer. Replace it. Clean and reliable power is so important. The next time you have a problem, you can cross off power supply as a possible cause and move it to the bottom of your troubleshooting checklist.

#27 10 years ago

Thanks guys. I'll probably end up using it as a practice board and get the new one.

My backglass is ok. Has a few quarter sized chunks missing, but it's not terrible. Why, you got a line on a replacement? If I get this thing as fixed up as I'm envisioning, I may be on the lookout for one.

The playfield still has the mylar on it, so it's pretty darn good overall. Got a big divot where the captive ball sits and a couple worn out spots just on the edge of the mylar. Paint under the mylar looks flawless, but of course it's faded elsewhere.

#28 10 years ago

boo... what do you know, powered up the MPU and I get a solid LED.

MPUled.jpgMPUled.jpg

#29 10 years ago

What are you using to power up with? Known good power source that fires up other boards?
No flashes/Always on: C14, C15 shorted, U16 bad, U15 bad, U9 bad, Reset line bad, valid power circuit bad, U19 bad

#30 10 years ago

First of all, you don't have power connected to the board correctly. Assuming the red jumper is 5V, you've got it going to TP6, the only result you CAN get is a locked on LED. Connect it properly to TP5.

--
Rob Anthony
Pinball Classics
http://LockWhenLit.com
Quality Board Work - In Home Service
314-766-4587

#31 10 years ago

Wow, I'm a novice but I thought I knew the difference between a 5 and a 6. Amazing how differently things work when they're powered correctly. Moved the red and I get 6 flashes. Much better.

Thanks for the idiot check!

BTW, computer power supply that I tested 5v and 12v before trying the board.

#32 10 years ago

Nice. Jumped the resistors now and got the 7th flash.

#33 10 years ago
Quoted from aobrien5:

My backglass is ok. Has a few quarter sized chunks missing, but it's not terrible. Why, you got a line on a replacement? . . .

No, I'm looking as well. not going to start messing with any resto on it until I get a line on a better bg. My arts basically all there but a lot of delamination around the edges.

2 months later
#34 10 years ago

I mentioned this was going to be a long project, right? So, at the point, I've pretty much got everything cleaned, and got the new rectifier board from Great Plains and got that installed. Put all the new plugs on fired it up and all my test voltages look good, so hooray! Now I've got a few more questions before I take my next steps. I've got a few under-playfield parts that have to be replaced (frozen solenoids, etc.), but I've got this part that's broken off that I don't know how to identify. It's on the switch for the pop bumper, but the parts catalog I found only shows the diode. It says Y5F 12V on one side and E .05M on the other.

Second question - I've got a wire that I believe broke off plug J2 pin 13 on the solenoid board. If you look at page 53/54 in the manual for the solenoid board schematic (http://ipdb.org/machine.cgi?id=1650) You see a dashed line going from pin 13 to pin 25. On my board, the other end of this broken wire is soldered directly to a trace that leads to pin 25 on the back of the board. My question is, when I install the new J2 plug, do I just loop a short wire straight from pins 13 to 25 in the plug? That just seems weird to me since that's not done anywhere else and why wouldn't it just be done on the board itself?

Thanks

IMAG0224[1].jpgIMAG0224[1].jpg

#35 10 years ago
Quoted from aobrien5:

It says Y5F 12V on one side and E .05M on the other.

That's a .05uf, 12 volt capacitor. Either 10 or 20% tolerance.

Do you mean connector J3? Someone with more experience on that era of Bally may have more input, but the way the schematic reads is there should be a jumper between those two pins on the connector. Not sure why someone would solder one end to the board.

I should add though, I'm not sure why it's a dotted line on the schematic.

#36 10 years ago

Yes, J3 thank you.

That capacitor seems surprisingly difficult to find, but I appreciate the identification!

#37 10 years ago
Quoted from aobrien5:

Yes, J3 thank you.
That capacitor seems surprisingly difficult to find, but I appreciate the identification!

That is a jumper...it connects TP1 to TP3...if you make that mod on the driver board, you don't even need that wire in the connector.

Ed at GPE carries. .047uf ceramic disk caps that work for this application, which is to lengthen the switch closure duration to ensure the MPU switch matrix scan "sees" the closed switch.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info

#38 10 years ago

Awesome, thanks. I've got to get more connectors from him anyway, so that's perfect.

I see the mod you mentioned, so thanks for that, too.

I'll be back in another two months or so after I've passed beyond these steps.

2 months later
#39 10 years ago

Just wanted to say that thanks to all the amazing help from everyone here and the instruction and board rebuilds by barakandl, this project is "done."

IMAG0277.jpgIMAG0277.jpg

#40 10 years ago

Woo Hoo. Congrats and have fun.

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