After years of pondering, suddenly I understand how a simple CPU can control dozens of lamps, LEDs, and other I/O well beyond the number of pins available. Thank you!
This is awesome. Nice to see as my middle earth just lost all lamps... only backbox is lit and the game coin ups and works, scores, and displays work. but no bulbs at all on the playfield.
It ended up being q5 on thr aux board! Fuse tested good and i was just hoping it wasnt any of the ttl chips on the mpu. Only clue was q5 was dead cold to the touch!!
Hello, I would really appreciate it if you could please answer a couple of my questions about Atari CPU board repair. The questions are at the very bottom, the supporting info is below. Thanks. I have two boards. The first one doesn't work after 17 years in storage and the other one died recently when the ball drained after about 30 or so games. These are both airborne avenger boards. They were both stored in an un insulated building. After it died they now both have an always low reset (it's not the button causing it) The problem I am having is that RESET, pin 40 of the CPU, is always LOW even if I remove the CPU from the socket. I have gone through the Atari troubleshooting guide a couple times, and have gotten to the part where it says "replace ROMS",so I burned some new ones and did the simple rewiring, but that didn't fix the problem(I know now that RESET should be flashing high and low with no ROMS installed.) I took a look at the schematics for the reset and realized that the third chip in the set of 6 is "switched on" by chip A1 and maybe B6, so I grounded pins 2 and 3 of the third reset circuit chip to test and the RESET signal flashed high and low like it's supposed to. Here is the very important question: Both of the boards have the same low reset problem (it's not the reset switch, as when I press that it goes high for a split second and then returns low) The next suggested thing to do in the Atari troubleshooting guide is to replace the CPU, and I have noticed that the board that died when the ball drained already had the CPU replaced with an AMI one. Could this mean that the CPU is bad on both of the boards? Is the reset signal "switched on" by the CPU?(which is why it doesn't flash high and low until I ground pins 2 or 3 of the third reset chip) Does a CPU need to be in the socket for the reset signal to start pulsing? I've never gotten anything but garbage data when testing and experimenting so far which maybe can happen even without a CPU. Sometimes I could get the reset to stay for a few seconds but only garbage data was on the display line.
Hi Arty, fantastic video! There's nothing like tracing a problem down and the satisfaction of learning how....would you take an Atari Space Riders board in for repair if I sent it to you? Gotta love George Oppermans artwork! Thanks kindly...Skip
Sorry, but I just don't have the time for outside repair work. But hold on to your game. These are becoming increasingly rare because most operators are just dumping them into the trash since they don't think they are worth repairing. Unfortunately these boards are not the easiest to fix.
I'm pretty good at replacing components on pcb's, mostly work on Williams Bally boards but I'm just learning what to look for and how to troubleshoot as these are different. I've watched all your videos and have learned a bunch! Thank you for these...if I gave you the symptoms of what is happening with the game could you point me to some focal points or where I might look for the culprit(s)? I have clear schematics and the entire service manual... Thank you sir! :)
Well, would you be willing to help troubleshoot another board? Basically, I've got score displays and play field lights, and the flippers work when the game is turned on but no other solenoids function at all. You're not able to start a game. Any clues as to what I need to check?
i'm trying to follow this troubleshoot, and, am wondering if the problem was a bad chip, or, just solder splashes from a previous repair attempt? or, even that initially spotted solder splash that was found visible n the board.
My guess is that the 74367 was bad, and on top of that there were solder splashes underneath that chip from where they had tried to reconnect cut pins.
I haven't found anything pin compatible. The solution would be an adapter board utilizing small capacity SRAM chips and additional decoding/buffering circuits.
can you make a video on how you managed to own so many atari pinball machines? I have one as well, check out my channel! they are pretty rare up in toronto, canada!!
