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Asteroids / Asteroids Deluxe Board Repair Log

On Coronavirus lockdown for the past few days, what better way to spend the time, fixing 40 year old arcade circuit boards.  Pulled out some Asteroids and Asteroids Deluxe boards, getting much better at fixing these, here are some repairs from the past week or so and a few other tips on fixing them.

Some things I do first on all Asteroids boards (haven't replaced all sockets on AD boards yet, so far they seem to hold up better).

  1. Replace rom and 6502 sockets (if original), just good preventative maintenance.
  2. Burn new roms (if original proms show any signs of brittleness), check rom and CPU sockets.
  3. Put game in self test, listen for Ram errors.
  4. Check clock and reset line on CPU.
  5. Test ALL Voltages, including regulators near the front of board, 8.2 VDC at 4016s in vector section.
  6. Start in-depth testing with Fluke 9010a if you're lucky enough to have one and confirm program code is running.

Asteroids Deluxe, Dead (3/16/20)

  1. Board doesn’t do much of anything, cleaned roms, processor, nothing on power-up, board was watchdogging. Actually a fun repair as I figured out most issues relatively quickly, but probably still spent 3 hours fixing this one due to multiple issues.
  2. Used 9010a to test roms, none of them passed rom test.  Probed around on address lines, A7, pin 1 of roms stuck low. Input at 74LS244 (C1), pin 2 was active, output, pin 18 was stuck low.
  3. Replaced C1 and board now boots with video issues, asteroids stretched, video off.

  1. No activity on DACx8 line, pin 5 at D11 is stuck low. Output at D/E10, 74LS157, pin 4 is stuck low, inputs look okay.
  2. Replaced D/E10 and pin 4 is now pulsing, video still distorted, but maybe slightly better?

  1. No activity on DACx6 line, pin 7 at D11 is stuck low. Pin 6, D10 stuck low, replaced D/E10 again and picture much better, first “new” 74LS157 that I just installed was apparently bad.

  1. Probing around vector circuits, found pin 7 at F8, 7497 was stuck low. Replaced F8 to fix issue. Board now works...
  2. While typing up repair look over to see some large lines on screen, looks like player ship is now screw up. 
  3. Quickly found output at 74LS175 at M6, pin 6 was stuck low. Replaced M6 to fix board, again.
  4. Board lasted a few more hours before developing video issues during bench testing.
  5. Found dead outputs at A10, 74LS157, Logic Comparator confirmed IC was bad, replaced it and picture improved, but still not right.
  6. Output at D10, pin 9 was high (74LS374), input was pulsing. Replaced D10 and image is back to normal (again).
  7. Guess what? Board developed issues again during testing. 
  8. This time looked like something on the Y-axis before the DAC, took a little while to figure this out as all inputs to the DAC were pulsing, I was sure the everything the  Y Position counters circuit was okay. Finally noticed to DACY7* input to the DAC was pulsing but not right (used scope to notice it). Replaced 74LS374 at B10 to fix the problem.

Asteroids Deluxe Beeps (3/16/20)

  1. Board beeps on power up, two high beeps, one low beep. Manual indicates bad 2114 ram at M3.
  2. Removed suspected ram, installed new socket and new ram and board works.

Asteroids, Dead Board (3/13/20)

  1. Installed new processor and rom sockets as preventative maintenance, board plays beeps constantly in test mode, it is watchdogging.
  2. Use 9010a to test rams and roms, everything checks out okay.
  3. Replaced L6 to lift pin 1 to isolate program code from vector generator, board plays blind.
  4. Replaced 74KS42 at E7 and 74LS175 at M7, thought they might be the issue, no change.
  5. Swapped out Prom at C8, board now plays blind (no more watchdogging).
  6. Replaced TL082 at A12 as piggybacking led to some vectors.  Board now has some bad video.
  7. Replaced TL081 at B/C12 as piggybacking helped, slightly better picture, but everything now collapsed on Y axis, asteroids looked squished.

  1. Found bad output, pin 6 on 7497 at H8, replacing that brought picture back perfectly.

Asteroids Dead Board (3/3/20)

  1. Installed new processor and rom sockets as preventative maintenance, board plays blind, no Z output activity.
  2. Found bad leg (it wasn’t reaching board) 74LS109 IC at A9.  (D8 pin 14, HALT line was not pulsing).
  3. Board now works but 00 in score are off on boot (kind of misaligned) for about 10-20 seconds. Voltage at 4016s was -8.4 VDC at boot.  Replaced most caps in circuit and it seems to better, still a little high on boot, but calms down quickly.

Crystal Castles Board Repair Log

Found some free to time to dig through a box of Crystal Castles boards we accumulated over the years. Most of these were straightforward repairs, but I'm not complaining, here you go:

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 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 board booted properly.

Garbage on Screen (12/17/19)

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

Dead, Reset Low (12/12/19) –

  1. Poked around 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!

Xevious Board Repair Log

Fixed a few Xevious boards a couple of months ago, still struggle with the sound on these. I have a few that I just can't get the sound going right (static at times, music issues), finally threw them back in the box for another day.  As with any board using those Namco custom ICs (Dig Dug, Galaga, Pole Position), I recommend carefully removing them and cleaning the oxidation of the legs, seems to solve some problems.  Most of these fixes were fairly simple, involving socketed rams and processors.

Here's some of the recent repairs and some from a few years ago. Enjoy!

Xevious Video Board Repairs

Garbage on Boot – Bad 6116 at 2S.

Garbage on Boot – Bad 6116 at 2R. Plays by vertical lines in explosion of player’s ship. Bad 2149 at 6M, piggybacking fixed problem.  Died on bench, garbage on screen (flashing), bad 6116 at 2E.

Vertical Lines in some Video (10/18/11) – Video board issue, boardset booted up just fine, passed self test, but there were vertical lines in certain video portions (such as the “Xevious” in the title screen).  Piggyback 2148 rams at locations 5N, 5M, 6N and 6M.  Once I did 6N the video issue went away. Removed the ram (it is soldered) and installed a new 2148 ram and the video was good.

Vertical Lines in most Video (10/18/11) – Video board issue, boardset booted up just fine, passed self test, but there were vertical lines in certain video portions (such as the “Xevious” in the title screen).  Piggyback 2148 rams at locations 5N, 5M, 6N and 6M.  Once I did 5M the video issue went away. Removed the ram (it is soldered) and installed a new 2148 ram and the video was good.

Video Board has Garbage (10/19/11)  - Video board was not booting, came up with some garbage and would kind of reset/repeat the garbage.  Start swapping 2016/6116 Rams at locations 2E-2J.  Turned out Ram 2J was bad.  Replaced it and the board fired right up.

CPU Board Repairs

Continually resets – Bad Z-80 at 4A fixed problem.

Garbage and static sound – Bad Z-80 at 1N. Boots to Rom 6 error = 4C. Replaced 4C, but no change, replaced Z-80 at 4A.  Never fixed the static sound issue.

Boots and resets continually – Swapped out socketed ICs, bad custom 50XX at 6C.  Music was off, bad IC at 6L had no 32H signal.  Board died in testing, started reporting Ram 7 error. Replaced 6116 at 1H to fix problem.

Rom 6 Error on CPU Board (10/18/11) – Tried replacing Rom 4C which translates to Rom Error 6.  Didn’t have any affect. Swapped at the Z-80 next to that Rom at location 4A and the board booted up.

Atari System 2 Repair Log

Spent some time going from a pile of Atari System 2 boards I accumulated over the years as I had 720 in the shop that I was working on.  I didn't have any experience with these boards, but figured some had to be easy fixes and actually most of them were things like damaged traces or a bad socket, was surpised how many I got running. Here's some of the repairs, look out for broken crystals as well, I've seen them a few times on the video boards as they stand upright and get knocked off easily.

System 2 boards include 720, Paperboy, APB, Championship Sprint and Super Sprint, from what I've read they can be converted back and forth to some degree by swapping roms as well as the Atari Slapstic (security chip). Haven't tried it yet, but they CPU boards all look identical. I believe there were two versions of the video boards.  Repair logs follow, enjoy.

Atari System 2 Repair Log

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.

Atari Centipede Board Repair Log

I've mentioned it before that my board repair skills are decent, but not to the point where I can fix every board I come across. Centipede seems to be one of those boards that I either figure out and feel really good about my skills or spend a half day trying to fix one and ask myself why I even bother trying to fix them.  Here's are few repairs I made recently as well as some from way back. Enjoy!

One troubleshooting note on these, always put the game in test mode if it isn't working, ram failures are common and the self-test does a half-decent job of telling you what ram is bad.

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, replaced the crystal.
  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, 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 )showed garbage on the screen).
  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.

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 bad 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.  Watchdog was barking, tried disabling and test mode, but nothing. Swapped out four program roms (307-310) and the game came up with no background graphics.  Tried test mode and it reported a bad Pokey at C3 and bad ER-2055 IC. Replaced both of these and the board worked fine.