Asteroids rev 5 PCB bad X and Y output voltages

Probably just a dirty fuse holder. Clean it with a wire brush.

Now fix your ROM errors.

That actually looks like it could be a bus or decoder issue, because all ROMs are being indicated as bad.

Pull and test all ROMs in a burner. And as mentioned before, make sure none are installed backwards. You can also test them one at a time in the game board, to see if any one of them is killing the whole bus.

If that doesn't fix it, there's a bus or decoder problem, which requires a more in-depth repair. You may want to send it out in that case. I repair them, PM for details if needed.
 
View attachment 848179Oh baby. Life! So I found that the 3A slo-blo fuse at F6 that I previously replaced was giving about 10 ohms of resistance so I replaced it again. That explains why my voltage was off. Could that be an indicator of another problem or just a bad fuse? Got a handful of them from Tube Depot.
The pattern size seems small, but it's alive.

Some of the vectors seem to have a curve in them. It could just be the photograph. Try making the image bigger with the pots on the game board. It should just about fill the screen.

Like this, but not as wide. Keep the box on the screen.

1758302913262.png
 
It also looks like you are flagging ROM failures. ROMs 5, 4, 3, 2

From the 7th printing of the manual which covers your board rev:

1758303314737.png
 
I'd like to learn as much as I can about board repair so I'm going to give it a shot. I'll buy a ROM burner and see what I find. I'm sure there's a million threads on this forum about what the best burner is. Like I said before that one chip is hot to the touch and the rest are cool even after cleaning and using Deoxit.
 
I'd like to learn as much as I can about board repair so I'm going to give it a shot. I'll buy a ROM burner and see what I find. I'm sure there's a million threads on this forum about what the best burner is. Like I said before that one chip is hot to the touch and the rest are cool even after cleaning and using Deoxit.

Pull the one hot chip, then see if the number of reported ROM errors in self-test goes down. (In which case you might only see one error, for the missing chip.)

And yes, there are a million threads about the best burner. Good on you for knowing, and not making another one. :)
 
There are also threads about bus and decoder issues, if you need to find those.

You're doing great so far, btw. You'll get this figured out. Every question you could ever have about just about any arcade game problem, exists in the archives here.

If you aren't aware, the Advanced Thread Search page is the best way to drill through the 20-year archive of 500,000 threads here. Don't use the search widget in the upper right corner of every page. It gives different results, and not as good.

Also, see this post for additional tricks for using the search tool:


If you run into additional questions you can't find answers to, feel free to post them here. But you're on the home stretch.
 
There are also threads about bus and decoder issues, if you need to find those.

You're doing great so far, btw. You'll get this figured out. Every question you could ever have about just about any arcade game problem, exists in the archives here.

If you aren't aware, the Advanced Thread Search page is the best way to drill through the 20-year archive of 500,000 threads here. Don't use the search widget in the upper right corner of every page. It gives different results, and not as good.

Also, see this post for additional tricks for using the search tool:


If you run into additional questions you can't find answers to, feel free to post them here. But you're on the home stretch.
IMG_6674.jpeg
I appreciate that, thank you so much. No change to the error codes after removing the hot ROM and adjusting the X and Y pots gave me a bigger picture but the lines crosshatch are indeed wavy.
 
Ok.

FYI, the distortion you're seeing there can be fixed by adjusting the linearity pots on the deflection board. See this post and thread for linearity adjustment tips:

 
don't you just love when someone before you messed with it and then dumps it on you. you can't tell now but from the condition your board was in I would bet the rom was in backwards at one time
 
don't you just love when someone before you messed with it and then dumps it on you. you can't tell now but from the condition your board was in I would bet the rom was in backwards at one time
Doesn't bother me yet. The process has been fun so far haha
 
don't you just love when someone before you messed with it and then dumps it on you. you can't tell now but from the condition your board was in I would bet the rom was in backwards at one time


Totally. That's why I mentioned it.

I've made the backwards ROM mistake myself before. Brain fart when you aren't paying attention. I've done it with Pokeys, too. (Those actually can survive being reversed. ROMs and PROMs, not so much.)
 
The only ROM that can bring up test mode is J2. I'll order a burner and go from there. In the meantime, I'll clean all the control buttons and see what's up. All buttons beep in test mode except player 1 rotate right and hyperspace
 
Update: Progress!

I've burned a new set of ROMs and the game passes self test, test screen picture looks good, and the game works in attract mode. I haven't tested actual playability since I've got the control panels disassembled for cleaning, but everything sounds good... it just doesn't look good. I'm having some graphical issues that are easier to show than to explain so I'll link a video below. Could this still be a ROM issue or something else? I tried to probe around the vector circuit with my oscilloscope but it's too slow to pick up the actual glitches.

 
That looks most likely to be a Vector Generator issue.

It could be a lot of things in the VG, though. If the board isn't resetting, it could just be a bad position counter. However from the video, the glitching looks to be in both axes, not just one (whereas position counter issues tend to affect only one axis). Also, I can't tell for sure, but if the game board is resetting at any point, that would suggest possibly something further back, in the Vector Timer section of the VG.

Bottom line, you might want to send it out at this point, as troubleshooting the VG is more of an art than a science, and having additional tools like a Catbox can help. You could try piggybacking various chips in the VG and see if you can get lucky, which may or may not work. But digital/VG issues like that can be tricky to suss out.
 
Update: Progress!

I've burned a new set of ROMs and the game passes self test, test screen picture looks good, and the game works in attract mode. I haven't tested actual playability since I've got the control panels disassembled for cleaning, but everything sounds good... it just doesn't look good. I'm having some graphical issues that are easier to show than to explain so I'll link a video below. Could this still be a ROM issue or something else? I tried to probe around the vector circuit with my oscilloscope but it's too slow to pick up the actual glitches.

Looks like you are moving in the right direction.

Keep in mind, many of the ROMs you have to ERASE with a UV eraser before you can re-burn them. Did you pick up a UV Eraser?
 
I saw this problem and thought wtf. I should start a betting pool on what the answer would be. Don't have a clue where the problem could. but the voice in the back of my head would guess something around the adma data but that is just my wild a** guess with nothing to back it up. Probably a good thing to send it to @andrewb unless you want to risk shotgunning the board vg section
 
Looks like you are moving in the right direction.

Keep in mind, many of the ROMs you have to ERASE with a UV eraser before you can re-burn them. Did you pick up a UV Eraser?
Yes, I bought a GQ-4x4 and a UV eraser and verified that the chips were blank before burning asteroids rev 2 from here https://arcarc.xmission.com/archive/Web Archives/ionpool.net (Dec-31-2020)/arcade/atari/roms.html
First I tested the existing ROM chips against those files and found two of 3 to be bad. Vector PROM checked OK too. I experimented by burning a set of rev 1 asteroids and still have the same glitch.

When I probe the DACs with the o-scope I can still see the glitch happen so I assume it's upstream somewhere?
 
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