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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/

RIP Ken. Sad news.

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...

This is where he got the new board:

Customer ordered a new board ($400-500) and called me to put it in. Game now works fine.

Good to hear. I corrected the Photobucket link in case anyone else needs it.

...Everything was working fine until I put that Big Blue in. What's strange is that another pcb set I have that played blind but burns up monitors* is not playing blind either now, and it was never connected to that Big Blue. Maybe something came unplugged or a wire broke from pulling the brick...

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...

I have a logic probe. I just don't know how to read the schematics well enough to know if a signal I'm looking for is supposed to be pulsing, high, or low. I can look up chip data sheets to get the inputs and outputs and know my Boolean Algebra well enough to know if a signal is supposed to...

You really don't need a scope to fix most monitors unless you're just trying to verify a vector signal is coming in. I rarely need more than a multimeter, although a ring tester and ESR meter come in handy sometimes. You'll find plenty of examples in the monitor section of repairs I've done for...

XOUT and YOUT have been measured. XOUT: AC = .005 V DC = 6.0 mV YOUT: AC = .003 V DC = 4.7 mV When I check for AC (against the ground terminal I assume) the lug will initially read about .47vac but then quickly drops down to the values above and stay there. I did replace the sockets with...

You make excellent points but are missing one key aspect: I work for a local company and it's up to them to buy all this stuff and they won't do it because we rarely end up doing board repair. I fix tons of monitors, fix or replace bad power supplies, etc. My boss would rather talk someone into...

It's actually easier for me to change out 5 sockets than it is to go find some place that sells DeOxit locally and then use it. I don't want to wait for someone to ship me some. If the chip sockets are that crappy, then I should change them out anyway or my customer may end up with this same...