(Topic ID: 56144)

Bumper and slingshot problems *happened again*

By sed6

10 years ago


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  • Latest reply 10 years ago by Fanatic
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switch_matrix_space_invaders.pdf (PDF preview)

There are 60 posts in this topic. You are on page 1 of 2.
#1 10 years ago

UPDATE- This problem mysteriously resolved itself once. It started acting up again 8/16.

I got my first pin, Space Invaders, several weeks ago. After replacing some bulbs and fuses it is (was) fully working. Now I have this weird problem.

My thumper bumpers and slingshots seem to effect one another and I cannot figure out what changed or went wrong. Here's a rundown of all the problems that popped up at the exact same time.

-Left bumper triggers right bumper and left slingshot, but not itself.
-Lower bumper completely dead.
-Right bumper triggers self as it should.
-Left slingshot triggers self, but also triggered by left bumper.
-Right slingshot doesn't trigger at all, but it still scores.
-My right drop target doesn't reset.
-My ball kickout doesn't kickout anymore.

All the above symptoms appeared at the same time. Everything worked fine one night and went bad the next time I turned the game on.

So far I checked all the voltages on the rectifier board and they are good. I've also looked for obvious crossed wires and found none.

I'd appreciate any help you guys can give this pinball newbie. Thanks!

Scott
OKC, OK

#2 10 years ago

Bump for the day shift

#3 10 years ago

Try reseating the J4 connector on the solenoid driver board and J4 on the MPU. Just for a long shot. OH, and for starters have you tried the coil test to see what fires and what doesn't?

#4 10 years ago

I did reseat those and no luck. I also did the coil test. The kickout, right slingshot and lower bumper don't fire during the test. The right bumper fires when the left bumper does, just like in play.

#5 10 years ago

Welcome to Pinside sed6! I'm not an expert on early SS Bally, but I would like to ask if you have joined our local group? If not, please do, we would love to have you!

http://www.meetup.com/Oklahoma-City-area-Pinball-enthusiasts/

#6 10 years ago

I'll take a stab anyway. Do the cooresponding switches register properly in switch test?

#7 10 years ago

I'm no early Bally expert by any means, but it sounds like there may be some switch matrix issues. Check what kind of results you get in the switch test, and let us know. In this era of games, there are both switch diodes and capacitors associated on some switches. Check the offending switches diodes and capacitors if they have them to make sure none are bad or not connected, etc. With these games too, there are DIP switches on the CPU board that have associated diodes that, if bad, could cause some misinterpretation and problems with the switch matrix.

#8 10 years ago

Just in case you don't have the manual, here is a PDF of the switch matrix, I had some problems with my spy hunter that I couldn't figure out until I got my hands on the matrix. The non firing coils maybe fuses, I ordered a fuse kit from actionpinball.com and replaced all my fuses. Most of your problems look like no power going to coils, non resetting drop targets, slings that score but don't fire. Check voltage at all non working coils, if there is voltage check for "melted" coils, bound coils, replace if needed.
The bumper affecting another bumper and a sling seems like something you should be able to trouble shoot with the matrix, it may be just as simple as a bit of bare wire somewhere in the line.
Good luck

#9 10 years ago

Thanks all!

I did the switch test and all switches are good (well the clone chamber showed bad but that's because I forgot to remove the captive ball first and it hits the switch when the PF is elevated).

Clearly there is something, perhaps just one thing, that is causing the problem because all the symptoms appeared simultaneously. I doubt 3-4 resistors or diodes or coils went bad at the exact time, but what to I know.

I'll check the offending diodes with my ohm meter. Can I do the with them still soldered in place? I need a refresher on how to test the caps if someone can help me there. How do I test the coils, I have no idea there.

I do have the manual already, but thanks for the link.

#10 10 years ago

http://www.pinwiki.com/wiki/index.php?title=General (tied for first best site ever)
Bookmark this page, I have used it so many times I have worn the letters off the keys.
Check all your fuses with your meter as well, both in and out of the holders. They are probably the original fuses. They may look good, but test em anyway....
Good luck

#11 10 years ago

One thing you might try is to fire each solenoid from the solenoid driver board. To test each solenoid from the driver board to the coil, ground the transistor tab and that will fire the coil. You can then see if the proper coil fires or if multiple coils fire. I am interested in your problem because I have a nineball with a similar problem and I believe the platforms are similar.

#12 10 years ago

Back to the switch matrix. Here's the other 1/2 of that page of the manual.

// Error: Image 114875 not found //

It shows the columns and rows. Looks to me like all of my trouble solenoids are in the same column. But that's the switches it shows, not the solenoid wiring. That column looks to be labeled 31 and says A4J2-5. Problem is I don't know what to do with that info. Do I chase it to a wiring or connector diagram or does it point me towards something on the MPU?

Now to mix it up a little more I want to show a potentially bad chip on my board, my U1. Pins 12 and 20 are clearly buggered and all are well tarnished. The chip below in U2 isn't socketed or buggered and only slightly tarnished on the legs.

// Error: Image 114876 not found // // Error: Image 114877 not found //

Here another shot of my manual shows the pinouts of U1. It might even show what they do, pin 12 is a ground and pin 20 I have no idea. So again I don't really know what to do with this info.

// Error: Image 114878 not found //

I did go to pinwiki and found a reference there that says a bad capacitor on a solenoid can let it fire randomly. I do have some extra caps so I plan to replace them on the three thumper bumpers to start with. As to my next step, I'm not sure.

I appreciate any help!

Post edited by sed6 : Fixed the pics

#13 10 years ago

I would look at every switch in that column closely and make sure one isn't shorted to ground or a GI socket, etc.

#14 10 years ago

Dupe post...

#15 10 years ago
Quoted from sed6:

I've got to learn how to post pics it seems.

Its a pain in the ARSE, but save the photo to your desk top, open it in MS photoeditor ( or photoshop, gimp ETC), then select edit-rotate. Then "save as" whatever you want, then upload it.
Judging on that cockeyed pic
Remove ALL your boards (label all the connectors as you do) and check for poor "repairs" or hacks. If the boards look good replace the damaged chip, I could be wrong, but that dosen't seem like the correct chip, as the chip is three legs short compared to the socket.

#16 10 years ago

Forgot about photoshop App on iphone, its free and allows you to rotate and crop photos taken from your phone.

#17 10 years ago
Quoted from buffaloatx:

I could be wrong, but that dosen't seem like the correct chip, as the chip is three legs short compared to the socket.

Sometimes chips are socketed with bigger sockets than the actual chip requires. Looks like that is the case here, as the schematics detail a 24 pin chip, which is what that one is.

As for the chip, it's definitely buggered and needs to be replaced. Not sure it is the root of your symptoms, but it definitely isn't helping anything. And, if that's a SCANBE under that chip, it needs to be replaced too.

#18 10 years ago
Quoted from The_Director:

Sometimes chips are socketed with bigger sockets than the actual chip requires. Looks like that is the case here, as the schematics detail a 24 pin chip, which is what that one is.
As for the chip, it's definitely buggered and needs to be replaced. Not sure it is the root of your symptoms, but it definitely isn't helping anything. And, if that's a SCANBE under that chip, it needs to be replaced too.

What's a SCANBE? Where do I get it and the chip?

#19 10 years ago
Quoted from sed6:

What's a SCANBE? Where do I get it and the chip?

SCANBE is a type of socket used on some of this era games that are BAD news low quality sockets. The socket would say SCANBE on it. Vid has a great picture point to SCANBEs with an always replace line. They should be replaced with machine pin sockets or proper quality sockets from Marcos or one of the other pinball suppliers.

Looks like the chip is actually a ROM chip at U1. Like I said, I'm not the best on early Bally systems, so hopefully someone who knows these board sets better than I can shed some definitive light on exactly what you would need at U1.

#20 10 years ago

Quick update. I replaced the caps on all three bumpers. No change.

I also manually tested each coil, connecting the transistor to ground. They all fired. Most fired normally. However the left thumper activated itself and the right one. The right one activated itself and the center.

Where do I go from here?

#21 10 years ago

Again, I'm no early SS or driver board expert but shouldn't the solenoid drives be separate? It sounds like you have some that are shorted together. Can anyone chime in on this?

#22 10 years ago

I took a few hour break and joined the guys at Slingshots for some stress relief. Sorry we missed you! See you next Sat though.

One of the guys suggested any short would be in the wiring after the transistor. Makes sense unless something's bad on the solenoid driver board.

Speaking of which, I'm about to pull it and give it a through inspection. But I did notice a toasty cap in the bottom corner. Here's a pic.

I'm off to chase wires. Wish me luck!

image.jpgimage.jpg

#23 10 years ago

I replaced that cooked looking cap at Q18 with one robbed from Q1, and unused one. No change.

I also reflowed a lot of the solder joints on the back of the board. No change.

I read on another thread that the constant flexing of the pins can cause cracks. I should have thought to have reflows those as well. I'll do that and then try to mess with the boogered chip.

#24 10 years ago
Quoted from sed6:

I did go to pinwiki and found a reference there that says a bad capacitor on a solenoid can let it fire randomly.

There are no capacitors on solenoids. There are diodes on solenoids, and ss bally's have small capacitors on the corresponding switches as well as diodes. If the capacitors are bad it might trigger a switch-closure, but that is only for that switch. So there will be no other solenoids firing because of it.

Quoted from sed6:

Now to mix it up a little more I want to show a potentially bad chip on my board, my U1.

Regarding that U1 rom: "do not touch it". If it is working now, leave it as it is.
Without that rom, or when it has bad connections the game won't start at all.
If you want to replace it you will get another type of rom, and you will have to modify the pcb as well (different jumpers).

Quoted from sed6:

-Left bumper triggers right bumper and left slingshot, but not itself.
-Lower bumper completely dead.
-Right bumper triggers self as it should.
-Left slingshot triggers self, but also triggered by left bumper.
-Right slingshot doesn't trigger at all, but it still scores.
-My right drop target doesn't reset.
-My ball kickout doesn't kickout anymore.

The diodes of the switches are a possible cause of your problem. Or it could be a short in the wiring of the switchmatrix. The slings, bumpers and droptarget all share the same column in the switchmatrix.

However that does not explain why some coils won't fire. It can also be that the MPU is giving the wrong commands to the solenoid driver.

I suggest you put the game in the testmode and go from there.( the red button in the coindoor)

- First the switch test. With all droptargets up, and no captive ball laying on the target, no ball in the outhole the switchtest should indicate nothing.
Then close each switch by hand and see its corresponding number.

- Then the solenoid test. Does every solenoid work from the testmenu?

Doing these tests are easy for checking if it is a switchmatrix-problem, or a solenoid problem.
If all solenoids work fine in the test, that means the MPU is controlling them in a correct way.

#25 10 years ago

Thanks for the info. I'm glad I didn't mess with U1.

I've gone into test mode and the solenoids behave the same incorrect way. The problems I have during play I also have with the test.

I did however these each one manually, three different ways. Grounding the coil, grounding the pin on the wire harness when removed for the board and grounding the transistor. In all cases each solenoid worked properly.

I also tested the transistors and diodes on the board and all specked properly according to the Bally repair guide.

I reflowed the solder joints for the connectors on the driver board and cleaned the pins with an emery board (a temp fix I know), neither helped.

I'm 99% sure I've eliminated a problem on the PF. Next I need to check the output from the driver board to each solenoid. I need to check the volts on the misfiring ones to see if the board is sending out a signal to more than one pin. Then if so, why?

I did check chip CA3081 on the driver board, the so called pre-driver transistor pack. Again the guide gives a voltage spec of .1v for each leg of the chip I'm testing. My test shows 1.0v. But I'm don't think that's it because only a few of my solenoids are acting wacky.

I'm starting to lean toward a problem on the MPU. Anyone know what additional steps I can take?

#26 10 years ago
Quoted from sed6:

I did however these each one manually, three different ways. Grounding the coil, grounding the pin on the wire harness when removed for the board and grounding the transistor. In all cases each solenoid worked properly.

Very nice. That is a large amount of wiring/etc working perfectly.

Quoted from sed6:

I've gone into test mode and the solenoids behave the same incorrect way. The problems I have during play I also have with the test.

That means the MPU sends the wrong signals to the 1-16 decoder chip.
Can be anything from U11 (on the MPU), connector J4 at the MPU, connector J4 at the solenoid driver, to the LS154.

Chances are that the connectors J4 (both boards) needs solder reflowing.

Could also be corrosion or a dirty U11 on the MPU. Not very likely, because the game is booting properly, but theoretically it is possible that one leg is not making good contact. In that case reseating the IC solves the problem.

I'd bet on the connectors, most probably the one on the solenoid driver.

#27 10 years ago

Great info, thanks! I'll try those tomorrow night, I just couldn't get to it today.

#28 10 years ago

Okay just reflowed the connectors at J4 on both the MPU and the driver board. For giggles I checked the continuity between neighboring pins to rule out a short and also checked continuity between the pins and their first component on the board. Both checked out and none of it did anything to correct the problem of one thumper triggering another or a slingshot.

Next I'll try to reseat U11. I didn't do it at the chip at the same time cause I want to really isolate this problem...

Okay, edit. I reseated U11 and it didn't help either. I did notice that after I reflowed the MPU and hooked it back up that the led on the MPU went on solid green. I pressed the reset button several times and it went out. I then turned the game on and off and it did all 7 flashes and went back to its normal 1/2 broken state. I've done this a time or two in the past now that I recall. Is this normal or indicative of some problem I might not have identified?

Any other ideas anyone?

#29 10 years ago

In that case I would suspect the LS154 on the solenoid driver giving problems.

#30 10 years ago
Quoted from Richard_BoK:

In that case I would suspect the LS154 on the solenoid driver giving problems.

I'm not familiar with that part. Is it a chip? Can I test it or do I just replace it?

#31 10 years ago

It's the 1-16 decoder (larger chip on the solenoid driver). What it does is translate an output based on a binary coded input. So "0110" activates output 6.
If you know how it works you can test it with a logic probe (all of the inputs should pulse depending on the output selected by the MPU).

But you can also replace it.

#32 10 years ago
Quoted from Richard_BoK:

It's the 1-16 decoder (larger chip on the solenoid driver). What it does is translate an output based on a binary coded input. So "0110" activates output 6.
If you know how it works you can test it with a logic probe (all of the inputs should pulse depending on the output selected by the MPU).
But you can also replace it.

Cool. Pinwiki shows how to test it with a DMM set to diode mode, but the test seems limited in its results. For best results it recommends removing the chip (desoldering) for perfectly accurate results.

I can't find a source for that chip. Anyone have a link? Since it seems I have to remove it to test it, I might as well just replace it for a few dollars. Plus I don't know of I should or need to invest in a logic probe?

#33 10 years ago

Okay, tested LS154 and it looks fine. I used the DDM method found here.

http://www.pinwiki.com/wiki/index.php?title=General#Testing_an_integrated_circuit

Any ideas what I can do next?

#34 10 years ago

I pulled my main board today and reflowed all the connector pins. I also touched up a few suspend joints. No help.

My main board does have some acid damage. See anything that could be causing my problems?

image.jpgimage.jpg image.jpgimage.jpg

#35 10 years ago

Not really. If only all acid damages looked like this....

2 weeks later
#36 10 years ago

Wow, can't believe two weeks has passed. I'm kinda bummed about the solution still eluding me. Here's where I'm at; my bumpers don't all fire correctly, some don't fire and some fire others. My single drop target doesn't reset and my ball kickout doesn't kick the ball out. I've checked all the wiring, checked the transistors and resistors on the solenoid board, reflowed all the connectors on the MPU and SB and reseated all the chips on both boards. All signs point to a problem on one of those boards, but I don't know which. I just bought a logic probe, but I'm not sure what to check, next, with it. Any ideas?

I have though found some time to work on a few other things. I've purchased lighted buttons I plan on installing soon plus a bunch of LED's from Cointaker. I ordered a mix of colors and bulb types. After lots of fun with different bulb combos on the PF and backbox I decided I like their premium frosted non-ghosting. I still have to narrow down what colors go where but narrowing down the type will certainly save me some money (maybe if the ones I like weren't some of their most expensive that is. I'm gonna need over 100 bulbs between the PF, backbox and infinity mirror bulbs. Here a preview.

image.jpgimage.jpg image.jpgimage.jpg image.jpgimage.jpg

#37 10 years ago

Look at the difference a little magic eraser makes on the yellow and orange! I've got a lot of work ahead of me. But I've got to get her fully running, any help is appreciated!

image.jpgimage.jpg

#38 10 years ago

Bumpity bump for the weekday crowd. There's got to be a few people on here that know how to help. Please

#39 10 years ago

If you put the pf down with machine on and with hv active, does it fire? If so then probably just switch adjustment. Try easy stuff first. Vibration of bumpers and all!

#40 10 years ago

When running solenoid test, do the solenoids fire in the correct order? If they do not you are missing one of the encoded solenoid data lines which i think is your problem.

Find the decoder IC on the driver board which is U2. Place the game in solenoid test. Using a logic probe or even a DMM check U2 pins 20, 21, 22, and 23. These four lines should be moving during solenoid test. If one is floating (no reading) than you have a lack of continuity. If one line is stuck high or low and never moves you have a short or possibly a lack of continuity.

With the game off and using your DMM on continuity beep probe and look for where the lack of continuity is. The solenoid signals start at PIA U11 Pin 10 to Pin 13, go through resistors R97-R100, out on MPU J4 Pin 1 to pin 4, In on driver board j4 Pin 6, 5, 4, and 3, to driver board decoder u2 pin 23, 22, 21, 20. Trace each line through this path.

Most common place to have a problem is going to be MPU j4, driver j4, and the U11 PIA's socket.

Andrew

#41 10 years ago

She's alive!

I came home after a long day at work and turned her on with the flick of the switch. (See where I could have gone with that?) Anyway I entered into the solenoid test mode to perform Andrews suggested tests and voila, all the noids fired! And fired and fired, then missed. Shit back to my problem it seemed.

I hadn't touched a thing before or after so something made it not work again. Perhaps time (just seconds) or temp (maybe). So I attempted to replicate my actions. Literally the only thing I did was open the coin door and backbox. So I closed them both and fired her back up and she worked again! So maybe something in one of the doors? Nope, I continued the noid test and opened closed the doors and nothing changed, it still worked.

I'm going back to play and I'll post more soon.

#42 10 years ago

So I played a dozen games and it works fine so far. What sux is I don't know what was wrong. And of course this problem could pop up again. I have aspirations of really restoring this game and I'd hate to put the time and energy into that knowing this problem can pop up again in the future. Here's a short vid of the solenoids working properly. Sorry for the poor quality.

#43 10 years ago

If something sometimes works and sometimes not it's my experience that the solution can be found in bad connections / solder cracks.

And since you have an MPU with acid damage: I'd check for the traces on the MPU from U11 (pins 10-13, count from the lower/left side) to the connector J4.

#44 10 years ago

I've had seemingly random problems (though consistent in symptoms) on both my Xenon & Centaur, both were caused by shorts, Centaur from a wire stripped of insulation shorting on the chamber drop target casing, Xenon by a short from a broken off wire in the coin door, this problem tended to appear and disappear on opening/closing door, I'd check the wiring carefully for bare or loose wires. The Centaur problems particularly seemed weird and disconnected but were solved permanently when I insulated the bare wire.

#45 10 years ago

I wouldn't think the coin door could have anything to do with this issue. Sounds like a flakey PIA socket, MPU j4, or driver j4.

I would repin MPU j4 since the board is corroded. Corrosion will damage the male and female connector pins. Most likely place of failure in your case.

#46 10 years ago

I too think its time to repin some of my connectors. Male and female. I'll also start probing around on the MPU and see now if I can recreate the problem. A push here or tug there might reveal something.

I played another dozen games this AM and am really enjoying it! I e identified a few other things I want to sort out like a sluggish bumper and slightly slow upper flipper. It's those little things I can focus on now that its running properly. I do though have 3 PF lights out that I can't resolve. That will need attention soon.

#47 10 years ago

If a controlled lamp never lights, you have confirmed it has power, and the lamp board connector is good just replace the associated SCR on the lamp board. Never lighting or always on are the symptoms for a bad SCR.

#48 10 years ago

I did actually replace one of the SCR's for a bad light. It didn't fix the problem. Any ideas what to look at next?

#49 10 years ago

Test continuity from the bulb socket all the way to the leg of the SCR. If the line is open investigate where the break is. I would put money on a cracked solder joint on a single sided lamp board. Since your MPU battery leaked you may have damage on the lamp board (very common). The corrosion will get inside of the connector and the crimp pins will break.

#50 10 years ago

I will pull the lamp board and go over it more closely. The lamp will light off its neighbor but I don't know that I've chased it to the board. I'll do that first.

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