New to this forum but seems there is a lot of knowledgeable people on here that can help me out. I bought my first arcade about 4 months ago. I picked up a supposedly not working centipede for $75 to convert into a multigame custom arcade for my kids. Got it home and plugged it in and got some mushrooms on the screen so I decided to tinker a little to see what I could get. One of the edge connectors was burnt so I cleaned that up and the game fired right up. From that point I dropped the idea of the custom arcade (for awhile) and was extremely excited to have a working centipede. It was probably only run for about 5 hours a week at the most for a month with no problems. Then I tried to turn it on one night and I got nothing. I found that three of the fuses were blown and replaced those. After plugging back in I heard a pop and smelled what seemed like something burnt. I looked at the pcb and the +15 volt regulator had burnt up. I replaced that and got it fired up again with no problem. Since then I have had a variety of issues. After being on for about two hours it would randomly glitch and reset and erase my high scores. This happened for about two months (but only about around 20 hours powered on). A couple of weekends ago after turning it on I heard another pop. Took the pcb out and inspected and the cap at c80 had blown. Replaced that Monday and plugged it in and got nothing. That's when I started reading on the forum. From reading, it seemed to me I was looking at a power issue which I had never thought of before. I tested all my voltages on my a/r II and pcb and everything was in good range except my +15 and my 30. +15 was reading nothing and 30 was reading around 14VDC, around half of what it's suppose to. Found out my +15 regulator had blown again even though couldn't tell visually. Replaced that last night, voltages were all in range again both with the board plugged in and unplugged, and powered it back up and got a bunch of garbage which was then washed out by a solid red picture. This happens in test mode also. I don't get any beeps or anything. Tried cleaning connectors, checked all my voltages, everything was in good range. I took some VAC readings on the a/r II board and the +22VDC was reading 55VAC. There was another one (maybe the +12VDC, but definitely not the 5VDC) reading some VAC (less than 10 I think) but not as high as the +22VDC. I read something about ac ripple on the 5VDC being very bad but my 5VDC does not read any VAC. Seems to me that the 55VAC on the +22VDC is probably bad also though. One addition piece of info, when I leave power on the board the RAM at c8 gets extremely hot, to the point where I burnt my finger by just touching it for a second. I'm guessing this is probably shorted? I think this may be a power issue which I let go too long and fried my board. I was going to go the easy route and just buy a working pcb to replace mine but if this is a power issue, I do not want to put the working board in and fry it also. Anybody have these same issues? Suggestions on what's wrong and where to go from here? Any help would be much appreciated. I'm guessing from reading this forum that a new Big Blue and a/r II board rebuild would be a smart idea even if they aren't bad because they are 30+ years old but I am brand new to this and want suggestions from all that have experience first. I apologize for the long post but I wanted to be thorough and tried not to leave anything out. Thanks guys.
