Space Riders Pinball Error

[AtariShag]

I picked up an Atari Space Riders pinball last September and have been looking at it bit by bit but am still stumped. A fellow KLOVer came by and fixed it up a little bit, removing a lot of extra wiring that should not have been there. He also replaced the transistors on the main board and I have replaced the EEPROMs with a pair I bought off Marco Specialties. The issue continues as you can see in the video below.

If I remove one of wiring harness edge connectors like the yellow or the red (solenoids), the same thing happens. If I remove one of the connectors on what I think is the aux power PCB (the one on the center left that is attached to the side, next to some fuses), then the 0s on the bottom of the scoreboard continues to move along but no other lights flash and the game just buzzes.

Now one other thing - if I attach the power to the upper left solenoid that is supposed to control the left drop target, it will constantly fire. There is also a solenoid assembly (to a drop target) inside the game that is unattached, looks like the solenoid had melted.

I see that there is a person on eBay that does repair for the main PCB or the aux power board for Atari pins but if it comes to that I'd rather send the correct board the first time.

Here's the video:

https://youtu.be/MqizND1ke5U

Thanks in advance - this one obviously needs a bit of work but I would love to figure it out and get this into my arcade to boost my pin offering

 

[ed12]

first part u have a stuck switch
u should have the switch matrix in your back box

>Now one other thing - if I attach the power to the upper left solenoid that is supposed to >control the left drop target, it will constantly fire. There is also a solenoid assembly (to a >drop target) inside the game that is unattached, looks like the solenoid had melted.

2nd part same problem,but now u may have a blown transistor on the driver board
plus u will want that soleniod
and i am not sure whom sells them

ed

 

[neutrino]

u should have the switch matrix in your back box

No boards in the backbox, they're all down below the playfield. Also, Atari doesn't have a switch matrix. They used one "switch common" return line. Each switch's output used an open collector and was individually enabled/disabled by the MPU so that the same common return line could be shared. This is outlined pretty well in the manual.

 

[AtariShag]

No boards in the backbox, they're all down below the playfield. Also, Atari doesn't have a switch matrix. They used one "switch common" return line. Each switch's output used an open collector and was individually enabled/disabled by the MPU so that the same common return line could be shared. This is outlined pretty well in the manual.

Thanks, so is the fault with the MPU in this case? I see in the manual where it discusses the MPU controlling the switches but I have zero experience on Atari pins or pins of this age.

One of the transistors blew when we first connected the solenoid but they have all been replaced.

 

[bagheera369]

Neutrino...am about to have to work through some of that myself. I have a Space Riders as well, down here in Texas. It's taken a back seat as I have other projects ahead of it, but will have to sort out similar issues eventually.

I do have a contact down here, who's a pinball tech, and specializes in Atari's for his home collection...so I have an advantage, for when I get to it. I will ask him if he's taking work, and if so, I will pm you with his info.

Absolutely correct about the backbox, which is why the Atari backglasses always look so nice...cause there was no extra heat back there to tear up the glass.
I have a complete set of schematics, so if you don't have those, I will get to work scanning on them, so I can get a set off to you via PDF.

Good luck on the repair, and I'll be keeping eyes here, to log for later down the line.

 

[AtariShag]

The schematics are here (in case anyone ever needs them) although I'm not experienced enough to really understand everything that is going on here. From what I gather, I need to look over the board for a short somewhere from the Switch Circuitry (or perhaps the MPU is bad?)

http://mirror2.ipdb.org/files/2258/Atari_Inc_1978_Space_Riders_Manual.pdf

Houston Pinball has an Atari pinball PCB repair on eBay, I might end up doing that to get it fixed in this regard...I did get a rubber kit and new flipper as it needs that too.

 

[KenLayton]

Marco Specialties sells Atari pinball coils.

 

[ed12]

4 lines of switch data tied to 1 ground common

there is a self test button
i think u should try it.instead of thinking u have a blown micro

ed

 

[neutrino]

Thanks, so is the fault with the MPU in this case?

It's not clear to me where the fault is, but I would suspect that it's more fundamental than just a stuck switch...I'm wondering if the MPU is resetting. The reason is because of the GI flashing. It shouldn't be flashing, it should be on solid. Unlike most pinballs, Atari pinballs need the MPU to be functioning properly to have the GI working. You can check some youtube videos for how the lighting should behave normally. If it were me, I'd probably start by putting a logic probe on the MPU's reset line and see if it's continually resetting.

If I remove one of the connectors on what I think is the aux power PCB (the one on the center left that is attached to the side, next to some fuses), then the 0s on the bottom of the scoreboard continues to move along but no other lights flash and the game just buzzes.

If you removed the connector that attaches to the Aux board from the main board, I would think what you witnessed is expected behavior. That connector is used to drive all lights including the GI as well as audio. Other data such as switches on the coin door, slam, start, etc. are also routed from the Aux board to the main board here.

The power for the displays comes from the Aux. board (+/-90 volts I believe), so it makes sense that the display is still powered. The actual data to be displayed is generated on the main board however and transmitted via the ribbon cable that attaches the display to the main board. So if the main board is not running, or not running properly, you're probably not getting good data transmitted to the display.

I'm not an expert on these machines, but I've learned enough about them to fix minor issues I have had with an Airborne Avenger and a Time 2000.

 

[AtariShag]

4 lines of switch data tied to 1 ground common

there is a self test button i think u should try it.

I did try that and the game keeps doing what it does as though nothing was pressed

It's not clear to me where the fault is, but I would suspect that it's more fundamental than just a stuck switch...I'm wondering if the MPU is resetting. The reason is because of the GI flashing. It shouldn't be flashing, it should be on solid. Unlike most pinballs, Atari pinballs need the MPU to be functioning properly to have the GI working. You can check some youtube videos for how the lighting should behave normally. If it were me, I'd probably start by putting a logic probe on the MPU's reset line and see if it's continually resetting.



If you removed the connector that attaches to the Aux board from the main board, I would think what you witnessed is expected behavior. That connector is used to drive all lights including the GI as well as audio. Other data such as switches on the coin door, slam, start, etc. are also routed from the Aux board to the main board here.

The power for the displays comes from the Aux. board (+/-90 volts I believe), so it makes sense that the display is still powered. The actual data to be displayed is generated on the main board however and transmitted via the ribbon cable that attaches the display to the main board. So if the main board is not running, or not running properly, you're probably not getting good data transmitted to the display.

I'm not an expert on these machines, but I've learned enough about them to fix minor issues I have had with an Airborne Avenger and a Time 2000.

Thanks for the advice and information. Unfortunately I do not have a logic probe and my knowledge in this area of electronics is still beginner level but I will see if I can grab a probe off of eBay, learn how to use it and check that. Thanks!

 

[bagheera369]

and all that, is exactly why I am saving this thread.

 

[trueno92]

I would think that the plugs were reversed on the left side of the mpu and its blown out the latch gates...

Ok, will this guy get into test mode? Each button press on the top switch insidr the coin door will cycle a different test mode.

1. Lights
2. Solenoids
3. Switches

I just did a bunch of trouble shooting on my middle earth. My videos are not terribly informative, but check it out as it may get you thinking about somehing....


https://youtu.be/VNEIYiWb20w