Centipede Audio Board Issues - 5v Low Randomly Too Low

TokensArcade

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My AR II board for my centipede has developed a bug on it's 5 volt line. I've had this Centipede for over a year and it originally would get garbled graphics and crash. I cleaned the connectors out and had no problems for over a year. It started acting up again recently sporadically so I decided to give it the full cap kit treatment. I used arcadeshops cap kit for the AR II (Which included resistors R29/R30/R5, Transistors TIP32 on Q2 and 2N3055 on Q3, the Voltage regulators 7812 at Q9 and 7905 at Q9, and all the 1N4004 and 1N5404 Diodes) and the main board capacitors, as well as installed a new big blue. Initially everything seemed fine and all was well. Until today where I had it on for a few hours only to come downstairs and see nothing on screen, no activity from the start button lights, but the boards power LED still on. I worked out that the voltage for 5v line was too low sitting around 2.5-3.5 volts and fluctuating. I went and took the AR II out to inspect it and then just on a whim decided to reflow all the solder again and throw it back in. BEHOLD! It was 5.2v again! Put the game board back in and everything was fine!

....Until about 10 minutes later when the voltage crashed to 1.11v and everything on the board shut off.

What could be going on here? I checked also that I'm getting the proper 36 volts AC input too. The only other thing that seemed off was that the 10.3 volt line was running at around 13v (In fact it may have been doing that before.)

All the other threads I'm seeing relate to the 2N3055 but I already replaced those.

Why would an issue like this be so sporadic? What am I missing here?

Any words of advice appreciated. Thank you.
 
Came back to it a few hours later, checked it again and it was pushing 5 volts again. Plugged everything back in the game. Ran for like 2 and 1/2 minutes before abruptly, dropping to 1 volt.... What in the world is this?
 
UPDATE:

Cause of issue found. So I'd recently bought a new pot of Solder flux. I had accidentally bought the yellow goopy kind for pipes rather than the white paste. This stuff was much stickier and thicker than the white paste.

After noticing how the power supply would start up fine then later lose voltage on the 5 Volt line I started to wonder if perhaps some flux was heating up, melting, and shorting the board. I also

I went and scrubbed the AR II thoroughly with distilled water and a toothbrush. I ran the AR II with no load for over and hour with no issue. I then ran it with the game board for over 6 hours and I had no issue!

Another day of stress testing later and it seems that was the issue! Not making THAT mistake again!
 
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