You might check my 7400/7500/2000/5000 repair log thread to see if I fixed a similar issue. It sounds familiar.
https://forums.arcade-museum.com/threads/some-k7400-k7500-u2000-u5000-repair-logs.193468/
Had someone give me a BBH Safari with a dead monitor. Fixed the blown caps and looked it over. Only other thing I've found is a crispy NTC (thermistor). Need a reference for a replacement. If nothing else I could try one off a D9200.
If you have a parts chassis and want to send me one, I'd...
Sorry yall. The web host crashed my page and lost all of the docs I had posted, and the computer with all the files lost the hard drive. I have paper copies somewhere, plus I saw multiple sites that just copied my pages (including the 'compiled by modessitt' tag at the bottom) so I figured they...
Well, my burner kept having an issue trying to burn them when set for the TMS2516, but an old Memory Book I found showed it crossed with the National MM2716 and that let me burn them just fine and they now verify as BZ chips.
Gave the board back to him and it still doesn't work. In Game Mode...
Can BZ be adapted to run on four 2532's instead of eight 2516's? And if so, how do you go about it? Don't see any jumpers on the board.
I have two v1 ROMs failing when verified against v1 files, and when read/saved and submitted to the online ROMident. One of the chips is a Synertek chip that...
Yeah, I know I fucked up, but it was late and I was tired. +5 was good so I didn't expect a problem.
Game is not playing blind. I haven't looked at it to even try test mode or anything. I did check voltages and the +5, +15, -15, and +5 DAC were all good. The 10.3 is close to 12 at the AR2 test...
I started with a completely working Tempest. I was working on another Atari (Millipede) and suspected I might have a Big Blue issue, so I swapped it into my Tempest brick to see if the game booted. Turned it on and got a speaker buzz and solid start buttons. Turned it off, threw away that Big...
Haven't gotten to probing yet, but the monitor did NOT work with the AD. The AD monitor was also dead so either the monitor still needs work or the AD has a problem with the vector output since it's playing blind.
I am getting a dot in the center of the screen, so the HV is up. Interestingly...
It IS possible to fix color issues with a cap kit because the color signals go through some 10uf25v caps on the neckboard and if they are going bad you'll get color problems. It's also possible the contrast and brightness circuits can be affected. And if the 12v circuit gets affected it can...
1) I was sure about the first and World, but wasnt sure about Exotica.
2) if you knew that, you should have caught the error. (J/K)
There are some differences between the 2000 and 5000 as far as troubleshooting. I have a big repair log on these somewhere here that might have something relevant.
I know. I have some spare DACs left over from any Asteroids repair long ago, so I'll check those inputs - tomorrow. I've had fun with that circular logic before, tracing back looking for a signal and ending up back at the chip I started at. Fun.
As far as the bench rig goes, I'm out and about...