(Topic ID: 227161)

Bally Black Jack 1977 MPU Led Flash issue


By Razal

9 months ago



Topic Stats

  • 23 posts
  • 4 Pinsiders participating
  • Latest reply 9 months ago by Razal
  • Topic is favorited by 2 Pinsiders

You

Linked Games

Topic Gallery

There have been 4 images uploaded to this topic. (View topic image gallery).

Untitled (resized).png
A (resized).png
DSC01422 (resized).JPG
s-l1600 (1) (resized).jpg

#1 9 months ago

Well this is it, I need your help. Bought this old Bally Black Jack, did the restoration and bought myself a new MM. Anyway here's where i'm stuck:
Game ON, Outhole kicker solenoid stuck, cut 1wire on the coil. Start the game, game Works fine, play/door test for about 5-10 mins doing the reset with ball on hand.
Turn game OFF, look at plug Q4 on solenoid driver (wich I think is relayed to it?) ... looks fine transistor brand new and checked. Solder back the coil turn game on. 3 Flash on MPU, turn game OFF, cut wire on coil. Turn game ON, 3 flash on MPU koil, dealer saucer coil stuck. Game OFF, cut wire on saucer coil, Turn game ON, 3 flash... chimes now stuck.... I know my wiring is good. Did all the test on door with all coils(when the game worked 5-10 mins). Can someone please help !!!!

s-l1600 (1) (resized).jpg
#2 9 months ago

Which chime was it? Do all those transistors test good? Do they still lock on if you unplug J4 on the solenoid driver board?

#3 9 months ago
Quoted from zacaj:

Which chime was it? Do all those transistors test good? Do they still lock on if you unplug J4 on the solenoid driver board?

First chimes 10 points, but it begun with outhole kicker... all those transistor tested good when I played the game 10 minutes.I still know that the wiring is fine and all coil and diode were tested and worked fine... When I unplug J4 the MPU board nothing moves. When everything plug in including J4... nothing moves.... Look like my solenoid driver not doing his job...

Thanks for you help...

#4 9 months ago

I'd try swapping the two pias

#5 9 months ago

During the 4th and 5th flash the CPU will logically try and flip all the ports of the PIA and then read back the PIA to make sure they actually flipped. You may even notice the continuous solenoid pull in briefly at this time and the sound board may squawk. If solenoids lock on at the 4th or 5th flash the PIA is probably bad or the CPU cannot access it properly due to a bad IC socket, busted trace, two output ports shorted together.... etc.

U11 controls solenoids and is in the "corrosion zone". So it wold make sense to look around there. If you have a known good PIA you could pull U11, give a good visual inspection for problems like snapped ic socket contacts. Then set the known good PIA at u11 and boot test again.

#6 9 months ago
Quoted from zacaj:

I'd try swapping the two pias

Quoted from barakandl:

During the 4th and 5th flash the CPU will logically try and flip all the ports of the PIA and then read back the PIA to make sure they actually flipped. You may even notice the continuous solenoid pull in briefly at this time and the sound board may squawk. If solenoids lock on at the 4th or 5th flash the PIA is probably bad or the CPU cannot access it properly due to a bad IC socket, busted trace, two output ports shorted together.... etc.
U11 controls solenoids and is in the "corrosion zone". So it wold make sense to look around there. If you have a known good PIA you could pull U11, give a good visual inspection for problems like snapped ic socket contacts. Then set the known good PIA at u11 and boot test again.

Ok thanks for prompt response!
Can you please identify the PIA on the board I need to switch? (I'm quite new to this don't want to mess it up!)
Cleaned and replace the battery in the "corosion zone".
See attached image of my MPU.

DSC01422 (resized).JPG
#7 9 months ago

The lower two big chips, U10 and U11

#8 9 months ago

U11 is a bit discolored in my middle where all the business gets done like it may be toasted. Might be one of the chips where they sanded down the imprint to put Bally's custom number on a motorola part. U11's socket might just be wasted too from the previous battery leak.

If you rotate U10 and U11 and if the flash count changes one of those PIAs is bad. Having a known good PIA to try would be nice. I'd try replacing U11 first.

#9 9 months ago

Ok here's what I did step by step.
Did a couple check on Solenoid Driver (checker diod IN4004 / Q1,Q4 behave funny, Q20) and all were fines. Plugged back the solenoid driver.
Took MPU swapped U10 and U11. Plug MPU on machine J4 only connected and got 3 flash.

Now outhole coil is not trigerred when power is on.
Also think i saw a blink* on Q12 transistor wich is new and tested. What should I do next?
Thanks a million again for all your help!

#10 9 months ago
Quoted from Razal:

Took MPU swapped U10 and U11. Plug MPU on machine J4 only connected and got 3 flash.

So is the game booting? Last reported you are only getting 3 flashes?
So if that's the case stop there. You have a bad PIA chip.

A huge red flag is you still have the battery on the MPU board. Get rid of it immediately! It may have leaked and has destroyed traces causing all this.

Since a bunch of transistors are locking up look upstream for a problem. Bad U2 or other chip on the SD board?
Also the fuse under the playfield should pop. Make sure it's a 1A SB fuse and not overfused.

#11 9 months ago

in theory only one decoded solenoid should be able to lock on at once. even if the cpu is running wild. The continous solenoids could still get held on tho from a locked CPU but if more than one locked on decoded solenoid indicates there is for sure something wrong on the SDB.

Since the flash pattern did not change with changing the PIA chips and assuming you counted the flashes right it probably means the MPU socket is bad. No 4th flash = U10. No 3rd flash = U8. Make sure you are not counting the "flicker" right at when the power toggle flips.

You can isolate the MPU from everything but power input to make sure nothing external is making the PIA test fail. On MPU only J4 plugged in and on SDB remove J4 and all the larger size 0.156" connectors if solenoids are still locking on.

#12 9 months ago
Quoted from BigAl56:

So is the game booting? Last reported you are only getting 3 flashes?
So if that's the case stop there. You have a bad PIA chip.
A huge red flag is you still have the battery on the MPU board. Get rid of it immediately! It may have leaked and has destroyed traces causing all this.
Since a bunch of transistors are locking up look upstream for a problem. Bad U2 or other chip on the SD board?
Also the fuse under the playfield should pop. Make sure it's a 1A SB fuse and not overfused.

Probably bad PIA
FYI the battery on MPU is brand new 3.6v and the MPU is clean of all corosion.
Also all Fuse are fine (including SB 1A playfield)
No coil are triggered now and SDB seems fine. (tested a bunch TIP-102 and IN4004)
MPU can't finish boot sequence.

Quoted from barakandl:

in theory only one decoded solenoid should be able to lock on at once. even if the cpu is running wild. The continous solenoids could still get held on tho from a locked CPU but if more than one locked on decoded solenoid indicates there is for sure something wrong on the SDB.
Since the flash pattern did not change with changing the PIA chips and assuming you counted the flashes right it probably means the MPU socket is bad. No 4th flash = U10. No 3rd flash = U8. Make sure you are not counting the "flicker" right at when the power toggle flips.
You can isolate the MPU from everything but power input to make sure nothing external is making the PIA test fail. On MPU only J4 plugged in and on SDB remove J4 and all the larger size 0.156" connectors if solenoids are still locking on.

So here's the situation:
Power ON, 3 Flash on MPU meaning :

Flick, Flash, Pause, Flash, Flash NOTHING.
(That's 3 flashes right?)

I'm going to try replacing U10 with a known good PIA.
Thank's again for all your help and support with this!
Can't sleep well with this in mind...

#13 9 months ago

Yep the missing 4th flash is U10.

I would not put another NC battery on that board when there are so many better alternatives. NVram is the way to go.

#14 9 months ago

OK got some update:
switched U10 with a good pia and still 3 flashes.
I'm starting to think to replace the socket for U10...
Is this a good idea?

#15 9 months ago

I can make out signs of battery damage on the photo but it doesn't get close enough to the affected area. Before you replace the socket try gently prying off the plastic cap leaving the pins behind. You need to work like a dentist. Take the crown off and look for signs of decay. Take a closeup photo of the U10 socket front and back and post it for our eyes.

#16 9 months ago

Ok so now the MPU is working.
Switched socket on 5106, U11 and U10. (COROSION ZONE)
All plastic desintegrate when removing the U11 socket.

NOW:
Got 7 flash on MPU (YEAH thank you guys) and now bunch of coil not working poping when testing.
Blowed up the 1 amp sb fuse on playfield.
Going to test the TIP102 again on SD.
+ my connectors look old...
Photo soon to come.
Thank you all for your help

#17 9 months ago
Quoted from Razal:

Ok so now the MPU is working.
Switched socket on 5106, U11 and U10. (COROSION ZONE)
All plastic desintegrate when removing the U11 socket.
NOW:
Got 7 flash on MPU (YEAH thank you guys) and now bunch of coil not working poping when testing.
Blowed up the 1 amp sb fuse on playfield.
Going to test the TIP102 again on SD.
+ my connectors look old...
Photo soon to come.
Thank you all for your help

sounds like you are in the home stretch.

All the solenoid signals come from mpu u11, leave J4, go to driver j4, to driver 74154 / Ca3081, to tip120. Usually j4 on both the MPU and driver need female repinned and male headers resoldered / replaced. Specially since your MPU corroded.

#18 9 months ago
Quoted from barakandl:

sounds like you are in the home stretch.
All the solenoid signals come from mpu u11, leave J4, go to driver j4, to driver 74154 / Ca3081, to tip120. Usually j4 on both the MPU and driver need female repinned and male headers resoldered / replaced. Specially since your MPU corroded.

not sure to understand what you mean by:
go to driver j4, to driver 74154 / Ca3081, to tip120
can you explain (i'm quite new to this)
Thanks!

#19 9 months ago
Quoted from Razal:

not sure to understand what you mean by:
go to driver j4, to driver 74154 / Ca3081, to tip120
can you explain (i'm quite new to this)
Thanks!

I was just mentioning the order or flow of how the CPU fires a solenoid.

A (resized).pngUntitled (resized).png

#20 9 months ago

Nice thank you for precision.
But now thank's to you guys my MPU boot up 7 flash.

I still keep blowing playfield fuse (1A sb) for some reason. Outhole selenoid is jammed when I power up the pin.
I know my Q4 (TIP102) is good and my wiring too.
PLEASE HELP!

#21 9 months ago

Unplugged the outhole coil and now everything works.
Whats should I do since i know Q4 is good and diode too.

#22 9 months ago
Quoted from Razal:

Unplugged the outhole coil and now everything works.
Whats should I do since i know Q4 is good and diode too.

Do you hear that solenoid lock on when you power up or does the fuse just blow?

If the fuse just blows measure resistance across the coil lugs. If you get a reading of 0 resistance cut the diode off of the coil and check again. If it is still shorted the coil is bad.

If the coil kicks and locks on right at power up something is still damaged in that driver circuit. If you put a new TIP102 in and it still locks on right at power up then the CA3081 (a chip with seven transistors inside of it) at U1 is likely bad.

If you want to do more testing to be sure... With a logic probe, or even the DMM checking voltage, you can confirm the CA3081 is the problem. With the fuse out or blown, put the game in solenoid test. For Q4 solenoid driver circuit, probe at U2 (the 74154 chip) pin 7. During solenoid test that pin should remain high (5v) and pulse down to low (0v) when the computer wants to fire Q4. If the signal is working there, then you pretty much identified it has to be U1 since you already replaced the main TIP102.

#23 9 months ago

OMG
IT'S WORKING!!!!!!
CHANGED THE Q4 AGAIN...
Now it's running smooth. Just need some fine tuning.
Thanks everyone this nightmare is over!
What a fun game!

Promoted items from the Pinside Marketplace
From: $ 155.00
$ 279.95
$ 279.95
$ 7.65
Cabinet Parts
Third Coast Pinball
From: $ 45.00
Displays
PinballSolutions.eu
€ 3.95
Flipper Parts
Multigame
$ 21.00
From: $ 169.95
$ 7.00
Electronics
Third Coast Pinball
900
Machine - For Sale
Rochester, NY
$ 11.95
Playfield - Toys/Add-ons
ULEKstore
From: $ 21.95
Apparel - Unisex
Pinball Wheezer
$ 5,800.00
Pinball Machine
Great American Pinball
$ 8,999.00
Pinball Machine
Little Shop Of Games

Hey there! Got a moment?

Great to see you're enjoying Pinside! Did you know Pinside is able to run thanks to donations from our visitors? Please donate to Pinside, support the site and get anext to your username to show for it! Donate to Pinside