bally freedom schematic

cadillacman

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DOes anybody happen to have the schematic for the power supply on a ss bally freedom? I think juat about any early bally ss power transformer rectifier schasmatic will work. Trying to make absoultely certial that i have a rare transformer failure.. ( got no 12vac on the output lugs of the transformer even with wires disconne3cted!
 

the second one was pretty close.. verified good ac inoput to the transformer and all good ac outputs EXCEPT the 12vac input that feeds the rectifier which also is not getting ac..

so basically, im hosed and it needs a transformer for sure.

ken, THANK YOU for finding the schems for me, im confident now that ive " for sure" found my damn issue. Now lets hope thats all thats wrong with this damn machine!


..... i wonder if i could find a robust 12vac transformer somewhere and hook it in......
 
I don't see why you couldn't wire in a seperate 12 volt @ 3 amp transformer to run your 5 volt supply. Radio Shack # 273-1511 ought to work.
 
foubnd one here lol.. ( its from the alarm sustem that weve never used never hooked up)

it puts out 15 vac but close enough to test my theory i supposed..

put it in, now i got 15vdc and drumroll.... locked on led on my mpu!

grrreat.. there three big chips( processors?) on the mpu that i used to have to pull and reseat to fix this, now that aint working.. so im gonna need to track those down now i guess..

when this first puked i messed with those before i realized i had a power issue so im sure i either killed em or ruined the connectors..


man this ss pin has just been a nightmare.. always something man!
 
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Have you checked all the voltages on all the boards? If those check good you could have battery damage on the MPU board. Very possibly the IC sockets on the MPU are bad, especially if they are the orange colored ones. These early Bally machines are easy to fix.
 
grrreat.. there three big chips( processors?) on the mpu that i used to have to pull and reseat to fix this, now that aint working.. so im gonna need to track those down now i guess..

That tells you the sockets are bad. Like Ken said, check your voltages.

Then check the reset circuit and replace the sockets if they're original regardless of who made them. If it's the original MPU it's a -17 and all of the sockets need to go for reliable operation.

You could also have used a switching power supply to solve your 12VAC problem. I would still consider doing that.
 
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yeah i thought of that too but at the moment i dont have any good ones lol..

doing it this way i did verify that my rectifier board is ok and the issue is definately in the transformer..


yeah this mpu was damaged by acid bad... one of the processors has also had a leg fixed...

i guess i need to get new processors and just solder them permanantly to the mpu bypassing those sockets ;D
 
i guess i need to get new processors and just solder them permanantly to the mpu bypassing those sockets ;D

You definitely don't want to do that. Install new sockets. If you end up with a bad PIA you'll be glad you did. There is only one processor on the board (6800 at U9). The other 2 40 pin chips are PIAs (6820 0r 6821 at U10 and U11).
 
The problems I saw with the early Bally electronic pinballs (and we had a bunch of 'em on the route) was those crappy sockets. I replaced ALL the sockets on the MPU board for more reliable operation.

I am assuming you have read the Bally/Stern pinball repair guides?
 
You definitely don't want to do that. Install new sockets. If you end up with a bad PIA you'll be glad you did. There is only one processor on the board (6800 at U9). The other 2 40 pin chips are PIAs (6820 0r 6821 at U10 and U11).

linsdey, i love ya man!


turns out i do have a bad socket at u11( one pin not contacting verified by making a jumper trmporarily)

but my main issue when i swapped them way back when is that i assumed all three were the same. Had one pia on u9 and one at u11 with the processor at u10

LOL DEE DEE DEE

swapped ti back to the correct spot, powered on, led blinking, blinking, BAM SHES ALIVE!! running on adt alarm power lol

so, i got some new pias coming anyways so i will do the sockets and new pias at least while im at it. I think im going to use my burgular alarm transformer hack untill i find a good transformer through here..

wheres the best place to get the correct pia sockets lindsey?
 
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Those three chips (the 6800 cpu and the two 6821) use common 40 pin IC sockets like Jameco # 41111 or Radio Shack # 276-1996.

Jameco # 662629 is the better quality machine pin sockets.
 
gotta find a transformer for sure now.. whatever went open on the 12vac shorted to another winding because now when i power it up im getting goo bubling out of the original transformer at the 12vac output wire area and smoke too.. DOH! oh well at least i verified whats bad on my machine.
 
We had to buy a new (actually used) transformer for a Bally Black Pyramid pinball a couple of years ago. Someone at one time had trouble with the score displays and stuck in a 20 amp fuse! Naturally it ruined the high voltage winding of the transformer. I found the cause of the original problem was a shorted diode on the rectifier board for the HV to the displays. Even running the transformer without the display winding connected to the rectifier board, the transformer was still smoking and blowing the line fuse after 5 minutes.

We bought the replacement transformer from El Dorado Games. It worked fine and the machine was put out back on the route for two years before we sold the machine about a month ago.

So it looks like you will also need to buy a transformer from El Dorado Games to get your machine going.
 
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