Atari Color Raster Games

I've fixed quite a few Atari raster circuit boards over the years. This page includes Centipede, Crystal Castles, Dig Dug, Millipede, Missile Command and Atari System 1/2 boards. Some of these are straightforward, some more complicated.

 Centipede Repair Log

• Clean edge connectors.
• Always put the game in self test mode and check rams as this is a very common problem.
• Check clock, V and H signals
• Check reset line, replace the processor socket if it is watchdogging before doing much else, then check 6502A.
• Replace any suspect processor / rom sockets.  Especially that shitty style.
• Check V and H signals, I’ve seen quite a few bad 74LS163s in the Sync circuit of schematics. Board may pass rom and ram test with Fluke when these are bad.
• If green screen, see if the game coins up and plays blind.

Narrow garbage screen (10/20/23)

1. Clean board, boots to some garbage on a narrow screen.  Reset line was pulsing, but not watchdogging. 
2. Quick visual inspection showed 74LS163 at N2 had a small chip and no outputs.  Replaced N2 and board now boots with video issues. 
3. Test mode beeps five times, bad L7.  Replaced 2101 ram at L7 and the board now works.

Some Lines on Boot (10/19/23)

1. Another fairly clean board, but not doing much on boot.  Clock signal looked good. Reset line was pulsing, but not really what I’d call typical watchdogging behavior.  Disabling the watchdog line caused it to go high, but still not working.
2. Used Fluke 9010a to test the bus, it was fine. Tested the 2114 ram and four program roms. All tested okay.
3. Probing around 74LS163s to check V and H signals I found that 74LS163 at P3 had dead outputs.  Inputs looked good and there was something near pin 15/16, solder or speck of something.
4. Removed  P3, leg 16 pretty much fell off and installed new 74LS163. Board now works.

Garbage on Boot (10/19/23)

1. Reset line was watchdogging. Clean board, but quick inspection showed a bunch of random program roms installed. Two 309 roms, two proms, nothing that belonged together.
2. Installed a set of known working program roms and board now works.

Dead (10/19/23)

1. Fairly clean board, nothing on power-up. Check reset, it is low, check clock and there is none.
2. Replace crystal, no change. Looks like the signal is there at N1. Check 74LS163 at P2, clock input looks good. Outputs are dead (6hz, 1H, 2H and 4H) 
3. or missing.
4. Replaced P2 and the clock signal comes back, game now works.

Video Issue (10/17/23)

1. Tagged has having a video issue from way back when.  Board boots with a  video issue. 
2. Put the board in test mode and beeps 10 times, which means bad ram at N5. Before replacing the ram I check the traces around it and find a band of traces that are scratches.  Clean them up, check continuity (it was good), retest the board and it works.  Guessing traces were smashed and touching each other.

Dead (10/17/23)

1. Very clean board, but dead. Quick testing showed no clock signal. Replaced crystal I have clock and blue screen.
2. Reset is watchdogging, used Fluke 9010a to start testing. Bus is good, passes the 2114 ram test. Passes first rom test (307). All other rom tests report the same wrong signature.
3. Poking around and don’t see anything unusual. Replaced processor socket as it was the shitty style (should have done this first).  Some signs of life, garbage on screen.
4. Replace rom socket for rom 308, now passes that rom test at times.  But not all the time. I’m stumped, eventually retest ram and it now fails, Ram DCD Error at bit 7.  
5. Took me a few minutes and replaced a buffer chip to no avail. Finally realized AB7 was shorted high.  Quickly figured out this was due to a solder joint at that new rom socket I installed. It was shorting high. Removed the solder from that pin and put new solder in. No more short.
6. Now passes ram and first two rom tests.  Good. Replaced the next two rom sockets.  Board now boots with vertical lines on screen. Push on graphic roms and that clears up. 
7. Install new sockets for graphic roms and the board now works.  Went back and replaced Pokey and last rom socket that I never did as preventative maintenance.
8. Probably should have just started with new sockets once it started failing all the rom tests.
9. During testing I pushed on this board to double check it and it would act up if I pushed on the graphic roms.  Basically the game would still run, but I’d get a bunch of Ps on the screen.  Turns out at least one of the graphic roms was bad or sensitive.  Burned two new ones and it's all better.

Sync Issue (10/16/23)

1. Board appears to be working, tagged as a sync issue and it came like slanted / out of sync. Colors looked okay.
2. Usually I just replace the last IC in the sync chain with something like this, but actually took my time and poked around this time.
3. Sync signals looked good, nothing seemed off.  
4. Checked continuity from composite sync to the edge connector pin 12 (solder side).  There was no continuity.
5. Visual inspection didn’t show a cut or broken trace.  Peeled back some mask to narrow down the break and finally found a very tiny break in the trace, definitely not visible with the naked eye. 
6. Fixed the  break and the board now works.

Bad Video (10/16/23)

1. Tagged has having video issues, about six years ago. Clean board.
2. Put it in test mode, beeps five times, bad 2101 ram at L7. Replace ram and it now beeps nine times.
3. Nine times = bad 2101 ram at N7. Replaced that ram and board now works.

M7 Ram Error (10/15/23)

1. This was a board I tried to fix five years. Tagged as “gave up”.  Beeps 7 times, looks like I had already replaced the ram at M7 and a few other ram near that location as well as N6.
2. Rechecked 2101 ram, it was fine. Probing pins on ram I found that pin 10 signal didn’t sound right, suspected a short or something. Some weak activity.
3. Traced this back to N6, pin 12, continuity was good, nothing looked off.
4. Continued to probe around the traces for this pin and found it was shorted to M8, pin 13 for some reason.
5. Visual inspection on top of the board showed a small scratch on a band of four traces near M7. Cleaned them up and rechecked and the short was gone. Smashed traces were the cause, not very noticeable. Board now works fine.

Plays, video Issues (6/2/22)

1. Fairly clean board, put it in test mode and got eight beeps.
2. Replacing 9101 ram at M5 per manual and board now works.

Green Screen on boot, board plays blind, two vertical line (2/18/21)

1. Checked voltages, bad 7815, replaced it.
2. Clean board, before I realized it played blind I checked processor, rom and ram with Fluke 9010a, all checked out okay.
3. Coined game and it played blind.
4. Worked my way forward and found pin 9 at 74LS153 at E8 was stuck high, and should be pulsing.  The IC checked out okay with the logic probe, but I replaced it anyway, no change.
5. Replaced the IC pin 9 feeds, the 82S25 (7489) ram and board now appears to work.
6. After testing I noticed that there were two vertical lines, about 1/8” wide going on the left hand side, basically “dead spots”, no graphics went through them.
7. Took a bit of tracing around, but found that VBLANK line was off on scope. Traced this back to a bad prom at P4 which fixed the problem.

Blank Screen on boot (2/18/21)

1. Clean board, already replaced missing crystal, not doing much of anything, clock and H/V signals looked good.
2. Reset line was watchdogging, replaced 6502A, showed signs of life, looked like it almost made it to test mode.
3. Replaced 6502A socket, still showing some signs of life.
4. Reseated program roms and it came back to life, replaced bad ER-2055. Rechecked the original 6502A and it was fine.

Nothing on boot (1/18/18)

1. 12 mhz clock signal looked good, but no 6mhz clock on test point.
2. Replaced 74LS163 at P2 and the board booted right up.

Nothing on boot (5/30/17)

1. No clock signal, 2N3904 at Q1 was bad. Crystal was damaged as well.
2. Board boots but reports ram error, three beeps, K7 is bad?
3. Replaced 2101 at K7, board still beeping three times.
4. Removed and socketed three other rams that were replaced at one point but weren’t socketed, repair worked looked decent, but wasn’t taking any chances. I’ve seen traces damaged in the past from stuff like this.
5. Still beeping three times, further probing showed floating outputs at K7. Also discovered 2H signal at pin 117 on rams K7, L7 and M7 was missing.
6. Checked continuity from N7, not there, repaired broken trace (that I couldn’t see) to fix the problem.
7. Board now beeps ten times. Removed and replaced 2101 at N5 to fix the boardset.

Solid screen on boot (5/26/17)

1. Reset button wasn’t working, so I replaced it.
2. Reset signal was stuck low.
3. VBLANK was WATCHDOG was not pulsing
4. Outputs on P3 (1V, 2V, 4V and 8V) were dead, clock signal input was good. Replaced 74LS163 at P3 and got some random garbage on screen. Piggybacking this chip did the same thing.
5. Board is now watchdogging.
6. Board passes long ram test on 2114 program ram using Fluke 9010a.
7. Program Rom 310 at J1 tests bad using Fluke 9010a, install a new program rom and board is now running.
8. During testing board started acting up, blank screen on boot sometimes, random garbage. Pressing on program roms and 6502 helped. Replaced sockets on 6502 and program roms and board is all better again.

Blue Screen (4/19/17) – Clean boardset that booted to a blue screen and that was about it. Swapped 6502, no change, put game into test mode and it beeped twice, indicated bad 2114 ram at F2. Removed, socketed and installed working 2114 ram to fix the boardset.

Plays, minor Video Issues (4/19/17) – I didn’t even realize the game had an issue until I played a game. Some of the centipede graphics were jumpy and other minor issues. Test mode reported a bad 2101 ram at L5 (six beeps), replaced this ram to fix the problem.

Board comes out of sync (1/27/16)

1. Tried board on Jamma test bench (uses negative sync as opposed to positive sync on my harness) and it came up okay.
2. Checked outputs for positive sync and they were stuck high.
3. Traced back to 7407 at A/B10, inputs looked good.
4. Replaced 7407 at A/B10 to fix the problem.

Board boots to blue screen (3/25/15)

1. Noticed  Q5 had a broken leg, replaced it (2N3904)
2. Board now boots to garbage.
3. Board was watchdogging, clock signals looked okay.
4. Fluke reported bad 307 Rom at D1. Removed and reinstalled and then reported it as okay.
5. Replaced rom socket at D1, board still booted to garbage.
6. Replaced processor socket as I’ve seen these style of socket be problematic.
7. Boards now works, but cursor goes right on game play and stays there (will move using trackball during game play but then reverts to right edge of screen).
8. Also while testing went back to garbage on screen.
9. Found bad rom socket at Rom 310.
10. Right issue was due to….

Board boots to green screen (3/24/15)

1. Boardset was watchdogging, clock signals looked okay.
2. Fluke reported program ram errors, replaced both 2114 rams at H2 and F2.
3. Board comes up with video issue (characters on right side of screen).
4. Stopped here

Board sometimes reports bad rom at F/H1 (3/24/15)

1. Seemed to work sometimes or was close but was reporting a bad rom at F/H1 sometimes, suspected bad rom socket..
2. Replaced rom socket and then used Fluke 9010a and it still reported a bad rom.  
3. Replaced Rom 209 and it booted and played fine on Jamma test bench with Centipede adapter.
4. Moved to Centipede test rig (using original Atari harness and power supply setup) to test track-ball and lost sound.
5. Replaced LM324 at J10 and sound returned to Centipede test rig.

Board boots with video issue (3/24/15)

1. Put board in test mode and it beeped three times.
2. Replaced 2101 ram at K7 and board now works.

Plays, but Garbage Letters on Screen (2/28/12) –  Put game in test mode and it reported  Ram K7, replaced this and it then reported Ram M7 bad. It looked like M7 was already replaced (but not socketed).  Removed M7, installed socket, fixed broken trace from prior repair and put a new  2101 Ram and the board worked.

Plays, but Garbage Letters on Screen (2/29/12) –  Put game in test mode and it reported  Ram K7, replaced this and it then reported Ram L5 bad.  Replaced Ram L5 and the board came up fine. 

Video Issues, Zeros on Screen, No Sound (2/28/12) – Game would play, but there were zeros on the first screen. Reseating the character roms and the problem went away.  There was still no sound, checked around LM324 amp and found that the output was dead (input was dead too, but I assume the LM324 was causing that).  Replaced LM324 and sound came back.

No Sound (2/29/12) – Didn’t even bother troubleshooting, just replaced LM324 amp and the problem was fixed.

Garbage on Screen (2/29/12) – Board booted with some random characters on screen.  Tried test mode, but realized test switch was stuck on, replaced test switch, still garbage, nothing from test mode. 

 

Crystal Castles Repair Log

Sprites have vertical line (11/16/23)

1. Issue wasn’t very noticeable, but sprites had a vertical line through them. Reseating sprite roms solved the problem.

Ram 4F Error on Boot (11/16/23)

1. Same issue as the last board.  Ram 4F was replaced at some point by someone else. They had to jumper some traces when they replaced it, but the work looked okay.
2. Replaced prom at 11L based on previous repair and board now works.  Thank god.

Ram 4F Error on Boot (11/16/23)

1. This board drove me nuts, kept reporting a 4F ram error, two high beeps and five low beeps.  Ram 4F was already replaced as well as the other ram when I last worked on it.  
2. Rechecked everything in the circuit and after replacing way too many ICs (a few buffers, a few ICs in Dynamic Ram circuit and circuits that drive), I finally suspected prom at 11L.
3. I pulled that prom from a parts board, installed it in this board and it now works.

Sprites Flickering, Colors not right, some distortion (11/16/23)

1. At first I suspected a bad 2149 ram as piggybacking changed things. Replaced both 2149s, but no change. 
2. Probed around the graphic roms and motion object circuits. Didn’t see anything off. Piggybacking ICs in this area didn’t help.
3. Grabbed a prom 10K from another board and piggybacked it.  Issue cleared right up. Removed 10K and installed a working prom to fix the issue.

Boots, coins up but Start Buttons don’t respond (12/17/19)

1. Inputs at buffer chip at 11C seemed to be behaving normally. 
2. Swapped the Pokey chip at 3D to fix the problem.

White Screen, Swirl sound on boot (12/17/19)

1. Board sounded close to working, had a white screen like other boards on boot and the swirl sound at boot, but stopped there.
2. Quick inspection show rom at 1N was a revision 205 rom, other roms were 300 series revisions. Installed 305 Rom at 1N and the board booted properly.

Garbage on Screen (12/17/19)

1. Board was beeping on boot, beeps indicated bad ram at 4E.
2. Replaced 4416 at 4E to fix the board.

Dead, Reset Low (12/12/19) – 

1. Poked around the reset circuit, noticed Q2, 2N3904 transistor tested differently than a known working board.  
2. Replaced, Q2, reset line now high, board still not working.
3. Swapped 6502A, board booted up.  Reinstalled original 6502A, board also worked. Reseating 6502A fixed problem.

Watchdogging, Garbage on Screen (12/12/19)

1. Swapped 6502A with known good processor. Board works!

 

Dig Dug Board Repair Log

Board tagged at Ram 2L error (12/8/20) – Tagged from 2004, which means I’ve owned it for 16 years and it has been sitting on a box for a long time.  Luckily my repair skills have improved since then, powered board up and it did report the 2L error. Visual inspection near the associated 2114 ram found a small scratch that broke one of the traces. Fixed the broken trace, board now reports ram OK, but just cycles constantly, doesn’t report Rom Ok.  Started by checking Z-80s, first one I pulled out had a bent pin, which I fix: Z-80 tests bad in known working board.  Swap in a good Z-80 processor and board now works.  Fourth board in a row with a damaged trace, which I caught very quickly, I’m learning from my past experiences (see below).

Nothing on boot (12/8/20) – Board tagged as “gave up”, no clock.  There was no clock signal on Z-80s, but 18 Mhz signal was good and ICs were replaced already in clock circuit.  Checked inputs to LS107 (3A in this case) and found that pins 4, 13, 10 and 11 were dead (should be 5 VDC).  Followed this trace and found a smash trace shorting on another trace on the top of the board near the IC that it went to.  Cleaned up the trace and board now works, third board today with a short like this, always inspect boards closing prior to doing anything else!  

Board booted up and appeared to work, but coin inputs were off, adjust dipswitches, but still was getting weird coin inputs (two button pushes for one credit), and game enter freeze mode even with that dipswitch set corrected.  Swapped out 40 pin customs 51XX and 53XX and board was happy. Cleaned and put the originals back in and it was still happy, looks like their legs were dirty.

Board booted to grid pattern and stopped (12/8/20) – Visual inspection found a small solder blob near 4D that look like it might have had a jumper wire attached at one point along with a small cut in the associated trace.  Checked my other boards, found no sign of jumper wire being there, so I repaired the cut trace and board now booted to game mode with a double sprite image very similar to another board I literally just fixed 20 minutes ago. 

Started probing around Motion Object Address Generator Circuit, quickly found that no signal at pin 12 of 74LS20 at 3P.  Output from 4P looked fine, checked continuity and it was not there. Found a very break in the trace at the solder point of pin 12, which I fixed to get the board fully working.

Board Boot to Ram 0L Error (12/8/20) – Replaced 2016/6116 at 9M, board booted to ram 3L error, replaced 2114 at 9H/J, but still booted to 3L error and also reverted back to 0L error a couple of times.  Visual inspection found some IC legs in that area that were smashed a bit, board was clearly bumped around a little and under some weight at some point.  Pulled up the smashed legs and now boot with a video issue, mostly double / triple sprites.  

Spent a bit of time pulling up other legs that were bent and possibly shorting to another leg, but no change. I moved onto looking for a bad IC in Motion Object Generator and Motion Object Address Generator sections replaced an IC or two that I thought might be the issue.  My gut told me this was still an issue due to bent IC legs on the back of the board, so spent so more time inspecting it and found a shorted IC leg at 3P (74LS20).   Pulled up the bent leg and board finally works again.

Board would Boot to Ram OK, then reset (5/31/17) –Boardset looked fairly close, would boot to “Ram OK” message and then reset and do the same thing over and over.  Bad Z-80 at 5H/J was the problem.

Garbage on Screen (5/31/17) – Not much sign of anything other than some garbage on screen, no indication of booting or bad ram/roms.  This was after cleaning all custom ICs and testing Z-80s.

Board was watchdogging, used Fluke 9010a to test the bus and D4 and D7 were tied together.  Took a few minutes, but found a smashed trace on the bottom of the board and a speck of solder causing the issue. Removed speck of solder and board now works.

Scrolling Screen, Video and Sound Issues (10/20/16) – Board had multiple issues, would boot up, but screen was rolling left to right, also noticed a video issue on the graphics and no sound.  Started trying to solve the scrolling issue, replacing 07XX custom IC at 4C resolved the scrolling issue.  Game booted up, still had a video and no sound.  Found 2148 ram at 7A missing (it was cleanly removed at some point).  Installed a new socket and 2148 ram to fix the video issue. 

Board still had a sound issue, sound would just pop here and there.  Replaced LM324 at 11H as these have a fairly high failure rate.  I did get some sounds back, but still not right. Did some probing around and signals out of 74LS273 IC at 12D didn’t sound right.  Replaced 74LS273 IC and all of the sounds came back.  

UPDATE: Turns out I didn’t fix the sound problem, it would work and then die, very random.  Pressing on a sound ram chip at 12C seemed to matter. When I was removing that I noticed one leg was never soldered in the board.  Installed a new socket and used the original ram and the board is now works 100%!

Rom 1 Error (10/19/16) – Board wouldn’t boot, looked it was trying to, would report Rom 1 error sometimes.  Pulled all custom ICs and cleaned them and it booted to game mode but the sounds were missing and/or low.  Replaced LM324 at 3E to fix the sound issue.

Ram 4H Error (1/28/16) – Board reported Ram 4H error which translated to 2114 ram at location 7M. Removed the old 2114 ram (it was soldered), installed new socket and another 2114 and board booted right up.

Ram 2H Error (2/13/12) –  Reported 2H error on boot-up, but that ram was already replaced as well as associated LS245 IC.  Replaced the ram anyway but got the same error.  Noticed the ram next to it had one signal stuck high so I replaced the associated LS245 with that ram. I got a different ram error now, 4-L, so I replaced this ram but still got the error. Swapped the two LS245s just in case the one previously replaced was bad.  The board booted once and then went back to the ram error on the next boot-up.  Put pressure on the first LS245 that was replaced (not by me) and noticed board would sometimes boot. Checked the traces on the socket and few looked suspect, so I remove the socket and found two traces that were damaged. Repaired the traces and installed a new socket and the board booted.

Ram 0L Error (2/13/12) –  This was the alternate board, but I was able to locate the ram based on the original layout and it translated to a 2016 at location 4K (the manual says 9M for the original board layout).  Replaced the 2016 and the board reported a Ram 3H error.  This 2114 ram was already socketed, so  I replaced it and the board booted fine.

Board Tagged as Resetting (2/13/12)- Board was marked as having reset issues. Plugged it in and it booted, noticed the crystal was loose, tapped on it and it reset.  Replaced the crystal and the board worked fine.

Board Locks up after Boot-up (2/14/12) – Board would cycle through start-up tests and then lock up right at intro screen.  Checked the dipswitches and dip switch for Freeze Game Action was set to On.  Flipped to Normal Game Action and the board worked.

Random Garbage at Boot (1/29/14) – Started by cleaning all the custom ICs as the legs were dirty.  Board started showing more signs of life, would get some Rom errors or even Ram OK once and a while.  Started swapping out Z-80s and found 3rd Priority Z-80A to be bad.  Board booted and played but the “pump” action wasn’t responding. Swapped 51XX custom IC at 1/2E to fix this problem, board works fine now.

Ram 3L Error (1/29/14) - This was the alternate board, but I was able to locate the ram based on the original layout and it translated to a 2114 ram at location 7L. Replaced the ram and board booted with audio issue.   Stopped there.

Ram 2L Error (6/9/14) – Board booted with Ram 2L error, which translates to 2114 ram at 9E/F.  Removed and replaced this ram to fix the board.

Garbage on Screen (6/9/14) – Clean boardset that booted with garbage on the screen. Cleaned the custom ICs but no change. Started swapping Z-80As and found that Z-80A at 6J/K was bad when installed in a good board.  Replaced Z-80A and the board booted right up and played fine.

Ram 3L Error (6/9/14) – This was the alternate board, but I was able to locate the ram based on the original layout and it translated to a 2114 ram at location 7L. Replaced the ram and board booted but with vertical lines on sprites and on title screen graphics (not the background graphics).  Noticed that 2148 Ram at 7A was removed at some point in the past. Replaced this ram and the graphic issue was fixed, board works 100%.

Boots to Ram OK Cycling (6/9/14) – Boards keep going through boot-up until it Ram OK and then would do the same thing.  Started replacing Z-80s and found Z-80 at 1N/P to be bad. Replaced it to fix the problem.

 

Millipede Repair Log

Same as Centipede, put board in test mode and make sure rams are good (board beeps if they are bad).

Fire Sound Missing (2/18/21)

1. Another board that was missing roms, burned new roms, board powers up and plays, but fire sound was not there, almost cutting out.  
2. Put in self-test, Pokeys pass self-test, but tried Pokey at 4B in another board and get no fire sound. Replaced Pokey to fix the issue.

Nothing on Boot (2/18/21)

1. Board was missing roms when I found it, burned new roms, visual inspection, powered it up, didn’t do much, reset line was watchdogging.
2. Another visual inspection showed Pokeys installed backwards, switched them around and it started beeping four times (2101 ram errors).
3. Replaced 4M, more, six beeps, replaced 4N, eight beeps, replaced L4, ten beeps, replaced K4, no more beeps and board now works.  Guess something took out the whole line of rams?

Nothing on Boot

1. Reset signal was stuck low.
2. VBLANK and WATCHDOG was not pulsing.
3. 8F looked good, went back to Vertical Sync Chain and tried replacing 8E as it looked rusty, no change. Also replaced 7D, but no change.
4. Replaced prom at 7E and reset signal came back to high, game came up, but a big white band in the middle of screen only the top and bottom lines of text were visible.
5. Game did play with sounds, just nothing on 98% of the screen, ran 9010A tests on program rom, program ram and video ram, everything checked out okay.
6. Started probing around Line Buffer area of schematics, noticed a number of outputs were stuck high at 9B (GRY0, GRY1, MOCB1, MOCB2). Replaced 93422 Ram at 8B as inputs looked good here, but no change. Replaced 9B, still no change.
7. Starting moving further down schematics Color Memory Address Selectors and replaced 9C, still no luck.
8. Moved onto Motion Object Color Selectors portion of schematics and piggybacked 8J, screen cleared up a bit, replaced 8J (74LS153) to fix the problem.  
9. Probably should have piggybacked these ICs first, but live and learn.

Beeped 5 times on Boot

1. Per manual replaced 2101 at L2.
2. Board now beeps 10 times, replaced 2101 at K4.
3. Board now beeps 9 times, replaced 2101 at J2.
4. Boards now beeps 3 times, replaced 2101 at M2.
5. Board no longer beeps and is working!

 

Missile Command Repairs

 Green Screen on boot (2/25/21)

1. Board was repaired by my in past, tagged as not working now.  It was watchdogging, used Fluke to test Roms, first Rom was bad at H1, odd as it was new and socketed.
2. Swapped rom, still fails test, trace back to 7408 at J6, which was socketed already and replaced.
3. Visual inspection showed pin 5 or 6 of the socket reamed to large, making crappy contact. Replaced socket and now passes Fluke test.
4. Still not working, test ram and it fails ram test, but no beeping self test mode.
5. Replaced ram at N4 as activity at pin 14 under Fluke test was different than other rams, board now works with no sound (reason why I didn’t hear beeping, I guess).
6. Replaced LM 324 as I was being lazy, suspected bad Pokey socket (Pokey was checked).
7. No change, replace Pokey socket, still no sound, double check external amplifier and swap it out with another, still no sound.
8. Move board to another test rig and sound works, something wrong a speaker or wiring on the first test rig, go figure.

Board boots to white screen, nothingness (5/29/18)

1. This was a eBay board, rom sockets were clearly replaced, new roms.
2. Clock looked good, board was watchdogging.
3. Ran Rom test using 9010a, everything failed, but signatures were ones I’ve seen before.
4. Realized Rom order was reversed when installed in sockets.
5. Reorganized rom order, now passes all roms but N/P-1. 
6. Visual inspection on bottom of board shows a couple jumpers from one rom sockets were installed, one was loose, fixed it.
7. Board passes Rom test, but still not doing much.
8. Ran Fluke ram test at 0-3FFF. Got R/W ERR @ 0000 BTS 60. Replaced P4 and then N4. I think N4 was bad.
9. Ran ram test again and get R/W ERR @0000 BTS 20. Replaced 4116 ram at M4.
10. Board now passes ram test and works!

Green Screen on boot (5/16/18)

1. Swapped original roms with known working set.
2. Roms H-1 and J/K-1 fails Fluke rom test.
3. Replaced 74139 at M5, no change.
4. Replaced 7408 at J6, now passes rom test.
5. Failed ram test with 9010a, replaced L6 socket.
6. Boots to Missile Command title screen then crashes.
7. Replaced POKEY and board now works.

No Sound (5/15/18)

1. Board was working, sound died in testing.
2. Used logic problem to check pin 37 at POKEY. Could hear the sounds being played.
3. Replaced LM324 at N10, sound now works.

No Sound (5/15/18)

1. Board was okay, but sitting in a box for a while, swapped POKEY and sound came back.
2. Original POKEY was retested and was  good.
3. Replaced POKEY socket and sound now works with either POKEYs.

Green Screen on boot on some of the monitor (5/14/18) 

1. Clock and reset looked good, board was watchdogging, I think.
2. Used 9010a and found a bad rom (forget which one). 
3. Replace the rom and board now boots.

Garbage on boot (5/14/18)

1. Reset was low, bad 74LS14 at D3, replaced, reset now high.
2. Boots to garbage on bottom half of the screen.
3. R/W error at 2000 BTS FF.
4. Couldn’t figure out the rest, board had a ton of work done to it, put it back in the box.

Nothing on boot (5/14/18)

1. No clock signal, 10mhz crystal missing. 
2. Replaced crystal, clock is bad, but board is watchdogging.
3. Connected 9010a, board, Data bus 0 stuck.
4. Turned board over, cleaned up some chip leads that were bent, retested, Bus OK.
5. K/L-1 Rom fails 9010a test, replaced it, board now boots but with video issues, screen mostly yellow.
6. STOPPED HERE

Flashing white screen on boot (was working) (11/6/15)

1. Boardset was working, clean set from a game I was restoring.
2. Disabled watchdog and the board went to game mode and worked fine, figured a watchdog circuit issue.
3. WDOG output at pin 5, E8 (7442 IC) was low, inputs to E8 were pulsing, looked good.
4. Replaced E8 and the board now works.

Random while blocks on boot (6/12/15)

1. Started by testing roms using Fluke 9010a and one was bad and replaced.
2. Tested ram and immediately got errors.  Replaced a couple of 4116 rams but no change, suspected it was not ram.
3. Started checking DRAM Data Input selector circuit and found MD0 stuck low.  Traced this back to BD0 and eventually a bad 74LS244 buffer at E2.
4. Passed Rom and Ram tests on Fluke, but still yellow screen, reset line was stuck low.
5. Spent too much time checking ICs and replacing a couple that were in fact good until I realized 7493 counter at D4 was replaced at some point and a 7490 was installed.  Removed it, installed a socket and a new 7493 counter and board worked.

Random while blocks on boot (2/6/15)

1. Started by testing roms using Fluke 9010a and some checked out okay, two checked out bad.
2. Checked Bus with Fluke and was getting bus errors, finally discovered a cap was shorting to trace (at least that’s what I think the problem was).
3. After spending way too much time figuring out the bus issue I confirmed the roms and rams were okay (replaced a few rom sockets as well).
4. Board came up but with a lot of green graphic interface, which was due to a bad 82S25 (7489) ram at L7.
5. Board has no sound.

Nothing on Boot (2/5/15)

1. Replaced processor socket first a preventative maintenance.
2. No clock signal, crystal was missing, replaced that to fix clock signal, but still not doing much of anything.
3. Used Fluke to test roms and found a bad rom at L/M1. 
4. Replaced bad rom and board fired right up.

White screen on boot, sometimes zig-zaggy white lines (2/5/15)

1. Replaced processor socket first a preventative maintenance.
2. Used Fluke to test rams and roms, everything checked, board not watchdogging.
3. Suspected something in Sync circuit, noticed 128V and 64 Signals were stuck low.
4. Traced this back to bad outputs on pin 6 and 7 from 74LS161 counter at B4.
5. Replaced B4 and board powered up with trackball issue. Cursor would not come back down after going up.
6. Tried shotgunning this by replacing C9, C11 and D9, but no change. Finally found it to be 7474 IC at J8 that was causing the problem.

Board Marked as Non repairable with a short (2/5/15)

1. Board had some work done, number of sockets replaced, all buffers replaced, but was missing roms and rams. Was tagged as “Not Repairable” by a board repair guy I used years ago.
2. Burned new set of roms and installed 4116 rams.
3. Roms pass tests on Fluke 9010a, but fail the first ram test (4116 rams).
4. Test mode reports K4 bad, but swapping it out led to no change. Once and a while it would report another bad 4116 ram as well.
5. Took a while but traced this back to a bad output on H3, pin 9 was stuck low. Replacing 74LS153 at H3 fixed the ram errors in self-test, but board still didn’t work, booted to white bands on screen.
6. Retested ram with Fluke 9010a and board passed all ram tests.
7. Started at Sync section, everything looked good, moved further down schematics and found M7 pin COLNUM2 was stuck low at pin 14.
8. Traced this back to dead LD2COL input at pin 9 on N7 (and M6, pin 9), which was caused by bad 74LS175 at C7. Replaced C7 and board booted with input issues, second player started not working, trackball not going left or right.
9. Replaced 74LS191 at K9 to fix the Player 2 Start button issue, but still having issue going left.
10. After replacing almost every IC in input circuit (figured it was C9 or D9, but it wasn’t) finally using logic probe I found that K9 pin 3 was shorted to ground. This was due to a bad 74LS244 at L9.

 

Atari System 1 Cartridges

Indiana Jones Carts

Card boot with Rom at 28000L and 20000L Error (8/19/2020) – Both errors corresponded to bad rom at 12A. Pulled rom and cleaned legs, reinstalled and board now boots with dots on background of title screen.

Starting pulling and test roms and found rom at 4C (136) was bad. Installed new rom and board works fine.

Cart came up with ”Farting” Noises (12/22/11) – Video looked good, but game was making farting noises at boot, no real sounds.  Replaced TMS5220CNL from another board at location 16H and the problem was solved.

Road Blasters Carts

No Cartridge Error (8/21/20)- Quick visual inspection showed that rom A11 was missing. Grabbed one from another board and it board booted up fine.

Game would boot with blocky Graphics (2/2/12) – Bad Prom at 7A. Replaced with a good Prom and the problem went away.

Marble Madness Carts

Cart Booted with Rom 20000 Error U (3/16/16).  Manual indicated this error was 15E, but that didn’t correspond with the version of the cartridge that I had.  Checked the manual and determined it was a program rom at B12. Burned a new rom and the board then booted to 6502 not responding error.  Did some rom swapping and found a bad sound rom at D16, replaced this rom and the boardset worked.

Cart Booted with Bank Switch Error (12/21/11) – checked the two slapstic roms (107 and 108) and one was bad. Replaced rom and game booted with 6502 Not responding error.  Starting checking other roms -401 to be bad. Also found a bad sound rom. Replaced these two roms and the board works fine.

Cart Booted with No Cartridge Error (12/21/11) –Starting checking the roms and found bad roms at -404, -403, -401 and a bad sound rom.  Board now comes up with video issues.  Starting swapping other roms and they were all good. Moved onto Atari custom chips 137415-1 and starting testing those in a known good board.  Found one bad one, replaced this and the board still has issues.  Moved on to the two PROMs and found one bad.  Board finally works!

Road Runner Carts

Game would boot, background graphics corrupted, character graphics off (2/2/12) – Bad Slag at 5H, replaced with another and the problem went away.

Atari System 2 Repair Log

720 CPU (3/9/21) – Popping and won’t coin up.

1. Quick schematic checked showed TMS5220C at 7D near coin input and speech circuit. Swapped that into working board and it produced same bad effect.
2. Replaced TMS5220C and board now works.

Super Sprint CPU (12/8/17) – Board booted to garbage on the screen, clock signal looked good, reset signal was low (normal) and data lines were moving. Checked program roms and ram, but they tested good in another boardset, which I expected. Was puzzled on this one as it seemed to be behaving normally based on other boards I looked at it.  After some probing around found that 14.318 crystal had a broken leg, replaced the crystal and boardset booted fine.

Super Sprint CPU (12/7/17) – Board booted to garbage on the screen, clock signal looked good, but board was watchdogging.  Checked program roms and ram, but they tested good in another boardset.  Pressing on the TII processor during boot-up got the board to show signs of life.  Replaced processor socket and board played fine.

Paperboy CPU (12/6/17) – Nothing on screen, just some white raster.  Quick inspection showed some traces that were scratched.  None were cut, but two were smashed together and shorted. Cleaned up the area, retested the board but still nothing. Clock signal looked good, reset line was watchdogging.  Swapped program roms and rams into known working board to find bad 6116 at 6P.  Board now boots up and plays but has a sound issue.

Self tested reported bad rom at 2D, replaced it but sounds were still off, but no longer reporting that error. Started swapping sound ICs and found bad YM3012 on row 8. Replacing that fixed the problem.  Rom error 2D popped back during testing, replaced socket and it is started working again.

Paperboy Video (12/7/17) –  Board booted with video issues. Swapping roms into known working board and found rom at 6T to be bad. Burned new rom to fix the problem.

Paperboy Video (12/7/17) –  Lines in the “paperboy graphic” on the newspaper screen.  Pressing on roms showed that it went away when I pressed on one.  Removed rom, cleaned legs and reinstall to fix the problem (forget which rom it was).

Paperboy CPU (12/6/17) – Nothing on screen, just some white raster.  Quick inspection showed some traces that were scratched.  None were cut, but two were smashed together and shorted. Cleaned up the area, retested the board and it came back to life.

Paperboy CPU (12/6/17) – Board booted with random specks of garbage on screen.  Removed T11 processor and reseated it, board came back to life.

APU CPU (12/6/17) – Board booted to garbage.  While checking program roms, noticed that two were in the swapped in the wrong location, moved them back to the proper location and the board booted fine.