Atari Color Vector Games

Gravitar / Black Widow

Gravitar: game did nothing on boot-up (4/27/12)– Quick inspection showed it was missing a rom and custom math chip. Replace both those ICs and it worked fine.

Black Widow: Garbage video, sometimes it worked (4/27/12) – This board came from a working game, so I suspected something simple, sometimes it would boot, sometimes it would not.  Put it on test bench and noticed the 4016s had tarnished legs. When I pushed on one of them game would come up sometimes. Replaced both of them for good measure and board worked again.

Star Wars

Sound Boards

Tagged as Popping (11/30/23)

  1. It was popping, didn’t actually start up a game, probably should have (more later).  Checked all the socketed ICs, they were fine.
  2. Retested and it started a game, still popping but I have all sounds but speech. Speech chip known good. Quickly found that it was not receiving clock signal at pin 6. Found good clock signal at pin 1 on 2F, but stick high on output pin 2. 
  3. Replaced 4069 at 2F, clock and speech are back.  Next time coin-up a game as I probably would have skipped testing the socketed ICs.

Sound Board, not doing much (6/9/14) – Sound board didn’t do much of anything, didn’t enter self-test for sound board either.  Processor socket looked rusty so I decided to replace and many of the socket legs fell apart as I removed them.  Installed new socket and 6809 and board had most sounds, but also some popping sounds in attract mode.  Noticed that 74LS374 at 5K (next to processor) had some rusty/questionable legs.  Removed, installed new socket and new 74LS374 and sound board now works fine.

Main Boards

Another Star Wars CPU board for the shop - Passes ROM tests for the CPU board, but fails AVG board ROM and RAM. Since the failing portions are on the AVG board, issue should be something they share, in this case it's the data bus that's causing issues. The CAT shows issues with DB05, driven from the LS245 transceiver at 0D on the CPU board. Scope shows all signals look good with the exception of pin 16 (DB05), which shows mid-level activity. Replacing this LS245 allows RAM and ROM tests to fully pass diagnostics.

Boots to video flickering, but it does look good (11/28/23)

  1. Swapping out socketed ICs and found that prom at 7L was bad and causing the flickering.
  2. Board now boots but is kind of locked up on the high score table screen. The high score table fades out and then just come backs.  Board doesn’t cycle past this screen in attract mode as it should.
  3. Roms checked out okay, reseating the 6809EP processor seems to have corrected the issue.

Tagged as “Good” 11/18 (11/24/23), Boots to Video Issues

  1. Kind of puzzled on this one as it was clearly repaired about five years and tagged as good. Booted to video issues / flickering, see picture.
  2. Used Fluke to start testing things, bus seemed fine, game was running from what I could tell.  Eventually found it failed Vram tests: “BTS 3 and 4 TIED”
  3. The Vram are on the AVG board, but failure was on the main board. I suspected something with traces, maybe smashed, but I knew the board had been repaired.
  4. Cleaned up traces are interconnect board, I didn’t see anything obvious, but when I retested board works fine. I think there was a bit of solder or something near those traces causing two of them to touch each other.

Blank Screen (6/6/14) – Board booted to nothing. Reset signal, clock signal, voltages were all good.  Swapped out program Ram at 2F/H and board booted with a Math Ram Error at 5H. Replaced this ram as well and the board now worked.

AVG Boards

Boots to Nothing (12/1/23)

  1. Fairly clean board, repopulated socketed chips with known working ICs and it boots to blank screen.
  2. Actually spent some real time for a change with visual inspection. Found a cut trace from 2A pin 6 to 3A pin 9. Not very noticeable, but a small scratch. Repaired the trace and board now works.

Tagged as having Video Issues (11/29/23)

  1. Didn’t do much on boot, quick testing showed a bad AVG. Replaced that game comes up but video is limited to a only part of the screen and gibberish.
  2. Input signals to both AM6012s looked good on scope. Removed DAC08 at 6D and threw in a working one. Video looks good and is back to normal.
  3. Ran self test and found another Linear Scale Issue. This time the square turned into a triangle at the tail end of test. Test resistance at R26 and it is at 710 ohms, should be 820 ohms. Noticed that C4 was replaced at some point. 
  4. Installed a new cap at C4 and resistance is back to normal and board now passes linear scale test.

Small diagonal line appears when “Star Wars” Spash logo goes away in Attract mode, Linear Scale Issue (11/29/23)

  1. Kind of similar to the last issue I had, this one was repaired much quicker though. The issue wasn’t very noticeable, but a diagonal line would appear at the end of the Linear Scale test.
  2. Checked resistors near 6A/B, everything looked good. Replaced AM6012 at 6A/B, no change. 
  3. Replaced TL082 at 7A, No change.
  4. Replaced DAC08 at 6D and board now works properly.

Large High Score Lettering, Linear Scaling Issue (11/27/23)

  1. High score table was oversized.  Found a bad DAC08 that fixed the problem (it was already socketed).
  2. During linear scaling test, it fails towards the end. The right side of the square starts moving outward on an angle.  During attract mode once “Star Wars” and the related story line gets to the of the screen it goes off to the right and distorts. It should get straight back down the center.
  3. Took me forever and a reference to another repair from Starbase Alpha Arcade to find R26 (820 ohms) in the analog output section cracked in half (not noticeable by visual inspection). Replaced it and all is good again.

Tagged as 3P Ram Error / Video Issue (11/22/23)

  1. Visual inspection showed that board had some scratches and minor damage near 3P Ram. Board was missing its socketed ICs.  Repopulate boards with good ICs and nothing appears on screen.
  2. Test voltage and +15VDC is missing. Replaced 7815 at VR1 and I know get video, but it is resetting. Probing around rams and I when I probe pin 18 on all rams video stops. Visual inspection shows a number of ram socket tails bent. 
  3. Straighten them up and board now boots with a ram 3P error. 
  4. Replace the socket at 3P and board now works.

Space Duel

Video Issue, occurred during burn-in testing (2/14/23) 

  1. Fairly clean board, was working that video became collapse, largely towards top of screen.
  2. Used to Fluke 9010a to confirm roms and rams were fine (I suspected they were as game was still playing with sound).
  3. Checked 74194s  with scope and logic comparator.  All signals looked good, ICs checked okay.
  4. Probing around DACs, noticed output at F9 was off compared to A/B9.
  5. Replaced DAC312 / AM6012 at F9 to fix the issue.
  6. Board started acting up again with video issues.  Replaced a few ICs in vector section, no luck.
  7. Replaced the other DAC312 / AM6012 to fix the issue.

Dead Board (3/23/21)

  1. Board didn’t much on boot, it was clean.
  2. Replaced original AVG, signs of life, booted up and played, but some parts of the video were sagging, number of ships by score were staggered down, some letters moving up and down.
  3. Replaced 74LS194 at C8, didn’t think it was the problem but it looked like a leg was cut.
  4. Still sagging, checked power and 5VDC was at 4.5 VDC.  
  5. Cleaned edge connector and adjust 5VDC and picture looks good again. Always check voltage first!

Plays, video a little jagged, looks like interference (5/9/18) – Replaced TL082s and DAC312s, but no change.  Recapped the axial caps in the -15/+15 voltage regulator portion of the board and the problem went away.

Dead (12/12/14) – Board did beep once when in test mode, otherwise dead. Replaced both 2114 program rams and it beeped three times, so I replaced the first video ram per manual.  Beeped four times and replaced the next video ram. After that it keep beeping four times, just went ahead and replaced all the video rams as it was failing video ram and video rom test on 9010a and figured one of the other two video rams was causing the issue.  Sure enough, board booted fine after replacing all four 2114 video rams.  

Dead (12/10/14) – Another board I worked on a bit before replacing roms, ram chips.  Board was dead reset was low, no clock at CPU.  After replaced some of the reset and clock ICs, I finally realized that my 10.3 VDC was low (around 6-7 VDC) at R73.  Noticed some corrosion near the trace and spent some time scraping it off and repairing the trace.  Plugged board back in and it came right up, but with a minor video issue: lines were more zigzagging the perfectly straight, almost like some interference on the video lines.STOPPED HERE.

Plays blind (12/10/14) – this was one of the boards I had attempted to repair earlier.  All rams were replaced, both video and program roms and rams checked out okay on the 9010a.  Game did coin up and play blind.  I could hear some vector chatter on the monitor and checking the X-Out and Y-Out signals on the scope looked like something was going on.  

Moved on to the Z-Circuit and color outputs and noticed they were dead. Traced the dead color outputs to K10, inputs looked good except for the STATCLK signal at pin 9, which was dead. Traced this back to 74LS32 at J6, inputs were good, but output was dead. Replaced J6 and the STATCLK signal returned and board come up with good video.

Nothing on screen (4/27/12) – Checked clock signal at processor, it looked good. Checked reset line and it was stuck low.  I started working my way back through the reset circuit and initially couldn’t find anything wrong except for WDCLR was stuck low and not pulsing.  I started tracing this back and replacing some components that drove it no avail.

Went back and rechecked the Reset and Watchdog circuit and found that the output on the counter at F4, pin 6 was dead. Checked the input and the signal looked good. Replaced F4 and the board came back to life.

Nothing on screen (5/8/12) – Checked clock signals at E4 and most of them were missing. Initially thought E4 was the problem so I replaced that, but should have checked the POR as it was stuck low.  Traced this back to the TL082 and the output was off on that. Replaced TL082 and the POR was now high and the clock signals good. Board kept reporting various ram errors. Replaced all 2114 and the board now comes with a small vector square that resets.  STOPPED HERE.

Nothing on screen (5/9/12) – Checked clock signals at E4 and most of them were missing. Initially thought E4 was the problem so I replaced that, but should have checked the POR as it was stuck low.  Traced this back to the TL082 and the output was off on that (looks like the 10.3VDC was shorted as it was reading 0 Volts). Replaced TL082 and the POR was now high and the clock signals good. Board now beeps twice, probably a bad ram.  STOPPED HERE.


Tempest Aux Boards

Mathbox Error “M” (2/8/23) – Checked all 40 pin mathbox ICs, they all tested fine. Found a bad prom at 131 at location K1.

Mathbox Error (12/9/14) – Pulled all 40 pin custom ICs and checked them, replaced all 40-pin sockets for them as it seemed touchy, but no change.  Swapped out all proms and they were good but the board did start running fine after I moved all the proms.  Bad prom socket or prom not seated well was causing the math box error.

Tempest Main Boards

Nothing on Boot, board was watchdogging (12/5/14) – This was a board that turned out to have multiple issues.  Something I stored along ago, didn’t know the history, but immediately found four broken pots so those were replaced before doing anything.

At first I wasn’t getting anything, no beeps in self-test, clock signal looked good, reset line was watch dogging, voltages tested good.  Using Fluke 9010a board passed vector rom and ram test but none of the program rams or roms checked out.  Started replacing 2114 rams and found bard rams at R2, R4 and P2.  At this point I could get it to pass program ram test on the Fluke, but still no luck with testing roms.  Didn’t think all the roms were bad, at one point two tested okay.  Tried replacing H2 and E2, but no change, decided to replace the 6502 processor socket as I’ve seen them fail, especially the style that was on this board.

Replacing got 6502 socket got me to testing program roms successfully with the exception of 122.  Pulled it and the socket was crappy looking, replacing that got the boardset to come up and play.  Did notice that tapping the analog vector section would cause the Y-Sizing to jump back and fourth.Also noticed that the Y-Linearity control did nothing.  Narrowed this down to C98, removed the cap and it fell apart, replacing that fixed the screen jump and the Y-Linearity issue.

Finally moved onto the auxiliary board (was testing the main board with a known good auxiliary board) and it reported a Mathbox message. This turned out to be a bad IC at location F/H2.

Blows F4 and F5 fuses on power block (6/5/14) – Narrowed the short down to main board and found that VR1 was reading shorted (in circuit).  Traced this back to tantalum cap at C56, which I suspected was the cause as I have seen many tantalum caps short on other boards. Pulled C56 and it was shorted. Replaced C56 and boardset booted with distorted video that appeared to be on the X circuit. Piggybacked TL082 at A11 screen looked to clear up, so I replaced this IC.  Also replaced X Center pot as it appeared touchy and video remained rock solid.  Let’s see how long it survives burn-in testing…

Nothing on screen (6/11/14) – Put board in self test and it beeped five times and then one long beep which translates into a Ram error at M4. Replaced the 2114 ram to fix the problem.

Spinner not working (6/11/14) – Aux board was the problem, spinner wasn’t responding.  Turned out pokey at B2/C2 was bad, despite passing self test.