Have you looked at the credit button switch to see if it maybe needs to be adjusted. Contacts might be too close together.

It’s acting *exactly* as if you hit the credit button, a totally normal game startup, credit decrement by one etc.?

That comment reminds me, isn't there something special about the Gold Ball -35 MPU re. zero crossing detect. I'm not sure about swapping them without the zcd mod.

Edit. Just checked in my Gold Ball the MPU is a -133, that was only used in a few games so it suprised me you have different mpus to test.

I’m gonna watch this thread closely. I’ve got possibly the same problem you are having. I’ve got a Elektra that also re starts like you started a new game on a single player game. Mine will also start a new game for a second player while playing. Gap is good. Clipped the cap on the start switch. No change. Different MPUs same problem.

My EBD has no cap on the credit button switch, not on the schems either. So if you have a cap on yours yes I’d try cutting that first.

This sounds like a switch matrix problem, Check your front door coin switches and make sure you do not have a stuck one. My read of the schematic, which has a typo in the strobe labeling, shows if you have a stuck coin switch and the #3 target is down the game will reset if you hit the matching bumper.

BIG AL HAS SPOKEN!!
Don’t know if this applies to my Elektra , but I’m gonna check this out.

Inkochnito has produced a great tech chart including the switch matrix to help troubleshoot
http://www.pinballrebel.com/pinball/cards/Tech_Charts/Bally_Goldball_Tech_Chart.pdf

This has reminded me, mine had a similar problem where it would tilt when a particular switch was hit. It turned out to be the small disk capacitor on the plumb bob. This post suggests can determine this in switch test - either way it sounds like you need to carefully go through switch diagnostics.
https://pinside.com/pinball/forum/topic/now-i-have-a-frustrating-bally-switch-matrix-problem#post-2902985

On Bally games nobody figured out for a long time how to wire a diode in series with a coin switch. That's why when one gets stuck it causes bizarre restart or tilt issues like this. Coin switches are part of the matrix, aren't we all , but not shown on the playfield schematic and look blank on the schematic.

I always thought that was odd there was no diodes on the coin switches. For sure those coin switches can get mangled and stuck always closed. Specially if someone hamfisted the switches trying to add credits manually.

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Sometimes I will write in the cabinet switches onto the playfield switch matrix chart when trying to figure out what the heck is causing a switch matrix problem. The strobe and return (I) numbers are the same even tho they go out two different mpu plugs.

Slam tilt looks like a reboot in many games. Some of the games with sound boards will play the tilt melody when slammed, but Im not sure if that applies to all games with a sound board. A Bally chimer will just straight up reboot when slammed. Which could be confused as a different problem than switch matrix.

There were no diodes on the coin switches because nobody could figure out how to solder one on.
There is an unused NC contact on the coin microswitch. Somebody finally figured out you could solder a diode from the N/C to the common contact on the coin switch and have a diode in series to prevent issues like this. Not sure if they ever got around to implementing the idea in production.

Interesting discussion. The Gold Ball cab wiring schematic shows isolation diodes on the coin switches and here's a photo of my machine so must have changed by 1983 (not shown on my earlier Vector). Pretty much all switches in the Gold Ball matrix are (or should be!) instantaneous (no drop targets etc) apart from "Outhole (regular)" and "Outhole - Gold Ball" so less opportunity for "phantom" closures.

mima have you checked switch diagnostics for any funnys?

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mima
Have you been able to make any progress with this?

Yes, the gold bullseye and two switches next to it should have capacitors (0.047uF, 50volt or higher).

GoldBall_PlayfieldSwitchMatrix_Capacitors.jpg

Those ceramic disk capacitors are not directional so can be soldered either way around. Some capacitors (electrolytic and tantalum) are directional though and need to be soldered a certain direction - best to ask.

In terms of which tabs on the switch to solder the caps to, its the tabs that lead directly to the leafs that make actual contact when the switch closes. If you're not sure, post clear pictures of those switches and we'll point to the solder tabs. You might even notice leftover cut leads on the tabs where the original capacitors once were.

Hi mima here's a pic from mine that might help. Your machine has little wear in that area - mine is hammered, I don't know why people aim at the centre target it's a drain monster.

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I'm having a similar issue with my Elektra. Game plays a 4 player round just fine. ONLY on Ball 3. Gameplay switches to the lower playfield on the LAST PLAYER. If the right lower flipper is held and the ball hits the center left target, The game resets as if the credit button was pressed.
I've replaced diodes and caps on switches and credit button. Still has issue.

Can you post a picture showing the actual capacitor markings and also a picture showing how that third switch is wired which we can't see?

What does switch test mode show when you press those three switches?

Ok, those closeup pictures reveal that someone has pulled the switch stacks apart and put them back together incorrectly.
It looks to me like the two lugs that the little diodes are connected to have been sandwiched together in the switch stack when they should be separated by one of the bakelite spacers. In other words the diodes are shorted because the connections are together in the stack.

The rear leaf that has the switch contact should be in the same position as the shorter tensioner leaf that is currently in the middle of the stack.

Carefully inspect some other switches and look at the spacing in the stack between the two diode lugs and the tensioner leaf - you might see what I mean.

some of the really cheap and small 473 ceramic caps will not last across switches in a Bally game. Its been a few years now but I had issues in a mata hari where caps like your picture would last one game to a one month before going close to short and making a pop bumper machine gun. I finally just left the cap off and made sure the pop bumper switch was adjusted well and its been fine for me. Stand up targets you probably want the cap on it tho.

If you think the cap is failing rapidly on you try a different capacitor type. Maybe a mylar cap or something will hold up better.... im not really sure tho.

If no body responds with pictures, look at post #23 above by astyy which shows the centre target and look at your "1-2-3" three yellow standup target switches for more reference.

mima I'm happy to provide more photo's if needed.

More reference photo's of central switch area.

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Post some clear pictures of how they're stacked now and where you are soldering the capacitors.

Also with one of those capacitors disconnected by one leg, put your multimeter in high resistance mode and tell us what resistance reading you get across both legs of the capacitor. You should get an instant reading of some sort that should then go open circuit. If you get a constant resistance reading across the cap it's likely faulty. When measuring, don't touch the meter tips with your fingers otherwise you will read resistance through your body.

When you're on high resistance mode (20M) you're not getting a reading across the capacitor which is correct.

However the switches still aren't stacked properly. The two lugs that the diode is soldered to needs a separator between them. You still have them sandwiched together causing the connected capacitor to make the switches appear as closed.

See this picture from astyy
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GoldBall_SwitchStack2.jpg

This is your stack setup - you need to make this change on all three switches.
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Goldball_LeafSwitches1.jpg

BTW, the pin header on the lamp board near the switches looks like it has a lot of cracked solder joints. You should resolder them all.
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GoldBall_PlayfieldLampBoard1.jpg

Take your time, with a bit of patience you'll get there. I know these can be very fiddly to deal with especially when they're still connected in circuit.

BTW, the leaf that the actual round target is attached to needs to be bent forward a little so it sits tight against the front tensioner. The rear leaf with switch contact should also sit tight against its tensioner. Essentially when you adjust the switch gaps, you do it by slightly bending the tensioner.

Goldball_LeafSwitchesX1.jpg

Good work guys! Enjoy your game!

Great stuff, your video brings back good memories - it's playing wicked fast.

Sweet game play. Set the Bally’s up hard and fast.... and try to hang on. Nice work to all involved!