HELP - Bally AS-32 sound board

jbk

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Donor 4 years: 2011, 2013-2015
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This SB made some squeaks and pops when I got it. Let's start with the speaker and MPU are good. All of the test point voltages test good 5v, 12v, and 43v, 67v on + of C17. I socketed/ replaced the amp at U9 and get 2v at pin 2. I replaced U1, U4, and U11 with their respective replacements. Reflowed all the pins at J1 and J2. replaced the caps at C17, C8, C11 & C6. Replaced the diode at CR3. Replaced both pots. The only problem I can find is the voltage between the shared points of R3 & R5 is 0.9vdc and should be 2.5vdc. I have added another ground point to assure it's getting properly grounded. I do not know why and cannot figure this out. If there is something I have overlooked, please point it out to me so I can get on with it. I'm tired of looking at this SB and need some sound on my paragon. It now makes NO sound at all.
 
The only problem I can find is the voltage between the shared points of R3 & R5 is 0.9vdc and should be 2.5vdc.

The voltage between R3 & R5 is supposed to be 0.8VDC, so the 0.9 that you're reading is correct.
Below is a voltage flow chart that I made for the (32) Bally Sound Board. I hope this chart helps you, because I still haven't solved my SuperSonic sound issue.

BD84B1B4-6FAE-47E1-91F8-15F155307E82-658-0000014448C71977.jpg
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I'm still working on it. It seems like everytime I make some progress I need to order parts and that takes another week.
 
Do you have access to a logic probe and oscilloscope? The probe can be used to test the digital section of the board while the scope can be used on both the digital and analog sections. It is difficult to repair these just using the voltage levels. If you get stuck I can repair these.
 
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