Bally MPU AS2517-35 help

[GatorMike]

Hi,

First pin repair here, so I have been doing a lot of reading. I have a 1982 Bally Pin with the -35 MPU board. Machine lights up when turned on but nothing else. No LED on the MPU board. I tested the test points and it is getting the proper 5v and 12v signals. The nicad battery was still attached so I removed it and did a vinegar/water wash and then alcohol to dry it. There appears to be the standard battery corrosion in the lower area. I did try a light sanding but it didn't seem to help, and to be honest I didn't want to mess it up any further if it is repairable.

Is there anyone in the Gainesville area that might have a working -35 board that I could test with to make sure this is the only issue?

Or anyone local that cares to look at the board and see if it is worth salvaging? It does look in decent shape to me, except of course for the corrosion area.

[HammysHangout ( Hammy )]

does the lamp blink at all?

[GatorMike]

No blink at all on power up. Never lights up.

[k7]

i've got 2 -35's that show no LED. research says it's due to a missing 12 volt input, or a bad LED, but my 2 boards have this issue due to corrosion and most likely, a damaged circuit or circuits on the reset area of the board.

i have 2 more -35s that are locked on. that shows a damaged reset circuit zone.


a vinegar mix will neutrilize the acid, but damage done will have to be sourced, and fixed. a good replacment or an alltek board may be the route to take, but if anyone wants to tackle these, i have 4 (not all mine) with various corrosion damaged zones to look at.

this is what the "book" says, so check j4, pin 12 for a clean 12 to 14 volts:
If the LED never lights, either the +12v (TP2, J4 pin 12) is missing or the LED is bad. By default, the LED is ON until the software tells U11 to turn it OFF.

[GatorMike]

Hi K7 - thanks for the input - I will check that pin.

Are you offering up those boards as "test" cases or do you intend on trying to get them fixed by a "pro"? 

[HammysHangout ( Hammy )]

i have fixed many -35, -100, -200 boards, there easy to fix depending how bad the battery damage is.

however, i'm currently not doing any work now, as i am booked with other projects.

[GatorMike]

I checked pin 12, reading right at 13v so I think that's good.

Looking like the board needs work but I'd like to figure out a cheap way to find out if this is the only problem before I either "attempt" to fix it or go with an Alltek.

[k7]

i just purchased a -35 off of eBay. i'm looking for a 2nd one.

no way to tell of any issues, unless you borrow a working as-2517 / as-2518 MPU, and put your working game roms into it.

my friend's boards, and my boards will go to someone eventually, but they all have battery damage. i know the reset section needs to be rebuilt on 2 of them, 2 of them i get no LED, so no idea what their issue is, and the last one, i'm very close to fixing (6 flashes with the wrong ROMs installed), but the playfield is gone, and i have boxes of new parts for it, so i won't know until i put it all back together.

post a want to borrow, see if we have anyone near gainseville that can help out. good luck.


p.s. - hamster, put me on the reserve list to look at 4 -35 MPUs.


i did forget the basics: clean the cables that bring power to the MPU, and clean the connectors on the MPU itself.

check voltages at the test points on the MPU itself. not all MPUs will have all test points, but basically:

TP1 = +5 vdc
TP2 = +11.9 vdc
TP3 = +21.5 vdc (comes from +43 vdc solenoid voltage)
TP4 = Ground
TP5 = +5 vdc - i think unregulated...

[GatorMike]

Thanks K7! I will post a want.

I did check all of the test points and they are within the limits.

[wildwest3163]

Im assuming this is the Speakeasy that was for sale there on the Northside of Gainesville?
if I remember right the other boards looked pretty good, but that MPU needs major work. I can send you the names of people that do that work if you need it

[GatorMike]

Yep that's the one. The MPU actually doesn't look that bad to me compared to some pictures I have seen online, but hey I'm new so it could be major.

Sure I'll take those names if you want to shoot them my way.

Depending on what they say, I may just get an Alltek Ultimate MPU for it. I may also try one of these corrosion repair kits, but I need to brush up on my soldering first. Not very good at soldering or desoldering for that matter.

[Rich Jax]

You will also have to update your solenoid driver board and rectifier board on this game. 

The C23 cap has probably dried out on your SDB and needs replacing.  This cap smooths out the 5volt to your MPU and you will get nowhere fast without a smooth steady 5v. 

There are 4 diodes on that model rectifier board that were undersized from day one that will also need replacing.  They power the GI if I remember correctly.

[GatorMike]

Great info, thanks Rich!