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05 February, 2017

Donkey Kong and DK Jr. Repair Log

Spent a bit of time going through some Donkey Kong and DK Jr. boards I've had sitting for a while.  Not included in these repairs are a few boards that had bad roms and/or bad rom sockets.   Boards with bad roms and/or a bad socket are fairly common in my experience and the first thing you should look at.  Also check the pots on the video boards as they tend to crack if the board has been banged around, the board will look out of sync if the pots are bad.

Donkey Kong Jr. CPU Boards

Jump Sound off Pitch, No Walk Sound (2/8/17) – This was a board I just fixed with the constantly thumping sound. Didn’t notice it had another sound issue until further play testing.  Replaced caps in jump section as well as some other caps in sound section, but no change.  Replacing 4020 IC at 6L fixed the problem, thanks to Scott Brasington for documenting this repair online.

Jump Sound Off Pitch (2/7/17) – Jump sound was out of pitch, just not right.  Replaced C24, C23 and C22 but no change.  Closer inspection showed pin 9 of 8L was never soldered properly through the board. The leg was bent and didn’t make it through the solder hole.  Looked like this was from the factory, the jump sound probably never worked properly. Was able to remove solder from hole, run a small metal lead through the hole and solder it to the leg to fix the problem.

Thump Sound Constantly On, No Music (2/7/17) – The “thump” sound from Donkey Kong jumping at the beginning of stage was constantly playing, no music was present. Initially thought this was a bad transistor as that seems to be common issue when sounds are stuck “on”.  All sound transistors tested good, swapped out the 8035 and sound rom, no change.  Recapped the sound section just in case, but no change.  Grabbed the logic probe and starting probing around before the 8035 and found pin 10 at 74LS04 at 6J was stuck low (it should have been high).  Replaced 74LS04 at 6J to fix the problem.

All Low Sounds (2/7/17) – Sounds were present, but very low.  Noticed R1 was burnt, replaced it, no change. Pulled Q1 and it tested bad, replacing C1815 at Q1 fixed the problem.

Donkey Kong CPU Boards

Garbage on Screen (1/31/17) – CPU boardset booted to garbage, went to pull Z-80 and test roms with Fluke 9010a.  Original Z-80 socket was replaced and the replacement socket didn’t look very high quality and poorly installed. Removed the socket, cleaned up the area as best I could and installed a new socket, board now works.

Garbage on Screen (1/31/17) – Fairly clean CPU boardset, complete, but boots to garbage.  Used Fluke 9010a to test roms and found program roms at 5C and 5F where bad.

One background sound during intro sequence out of pitch (after DK thumps) – recapped entire sound section, but no change.  Replaced LM724 at 8K and that fixed the problem.

Video Boards

Board had Mario Heads and Bottom on Screen (2/6/17) - Kind of an odd problem, it would boot up fine, after a couple minutes Mario's head and bottom would appear on the screen in the four corners (see picture).  Used some freeze spray to hit the chips and after spraying 2148 ram at 6R the picture would clear up again.  Replaced ram at 6R to fix the problem.

Sprites had horizontal lines (2/3/17) – Board looked close, but the sprites had horizontal lines running through them. Also a small horizontal line was on the title screen near the middle left hand-side.  Board had a fresh set of roms, swapping them into a working board, found rom at 7D to be bad.  Rom tested fine in burner, but didn’t work in the board.

No Sprites (5/18/12) – Board came up, but no sprites. Checked outputs at 3E and found a signal missing.  Replaced 74LS163 at 3E to fix the problem.  Thanks to Mike at Mike’s Arcade for this one, he had already documented the problem so it was easy to find.

Taito Stratovox Board Repair Log

A few years ago I had a few Stratovox sets, managed to get half of them running fairly quickly by swapping boards or they were already working.  Dug out the other ones this week and picked up one online as well.  Fun game, I'm guessing way back when the speech feature was really impressive.  Anyway, most of these were fairly straightforward repairs, roms falling apart, or other simple things, but figured I'd share anyway.

Stratovox does require a reset signal to boot up, so you're using this on a Jamma test bench or other test bench, make sure you provide it or the board will boot to some vertical lines.

CPU Board Locked in Test Mode - Boardset came up with some numbers and characters on the screen. After checking the manual I realized it was booting in test mode.  Figured the test switch in put was stuck, found an IC on the CPU board (10F) that I thought was the cause. While replacing it I noticed a scratch in the traces near it.  Replacing the IC didn't change anything, checked continuity on the damage and three traces were bad. Jumpered them and board came back to life. Should have inspected the board closer initially.

CPU Board Booting to Garbage - Clock signal on Z-80 looked good, while checking the Z-80, I noticed the first program rom (LS01) was installed backwards.  Pulled it, tested it in a working board and rom was bad. Burned new LS01 rom and board worked.

CPU Board Not Working - Didn't even bother testing this one, started by pulled program roms after looking at some of the legs on these roms.  Three roms had very brittle legs, a couple broke off when pulling them. Burned new LS01, LS02, LS03 2716 roms, installed them and board worked.

Game Board, Speech Issues - This one was lacking speech or most of it. Noticed that I listened very closely I could hear a blurb or something that sounded like speech.  Pinched sound pot on the very corner of the board together while game board was on and speech got a little louder.  Replaced 100K speech pot and the speech came back loud and clear.

Midway Rally-X Board Repairs

Picked up a Rally-X boardset last week, spent some time getting it going and a few others from the dead pile. I've always liked this game, something about the Namco designed games that I really like and this is one of them.  I've fixed a few of these sets over the years, some tips, ramblings and previous repair logs, enjoy!

Repair procedure (Stuff that I do before really going much further):

  • Inspect board for any damaged traces, etc.
  • Replace all masked roms with 2532 roms, just good preventative maintenance as the originals fall apart.
  • Make sure ribbon cables are good.
  • Use Fluke 9010a to test roms and 2114 ram on the CPU board (bottom board)
  • Clean legs on socketed ICs on video board.

Performing these steps first seems to solve a lot of problems with the boards I've worked on, similar to other games that use the masked proms where they tend to rust and become very brittle.

Top Board Repairs:

Random garbage on Screen/Video Issues (9/24/15) – Discovered that 9P, pin 3 was stuck low, replaced that, but no change.  Swapped at socket on 9R after confirming 9R was okay, but change.  Then realized that 8M and 8P were swapped and in the wrong place. Swapped them back and video issue cleared up quite a bit, but now a vertical line of cars instead of one car each.

Vertical Lines, no Playfield (9/24/15) – Initially suspected a bad ram, this board had 2147 ram installed, thought 9E might be the problem, but no changed. Noticed output on 9F at pin 15 was stuck low.  Replaced 74163 at 9F to fix the problem.

Playfield Missing (9/24/15) – Right side of screen was okay, but the complete maze/playfield was not visible.  Found 10E (93415 Ram) was stuck high at pin 7. Replaced ram and board worked.

Bottom Board Repairs:

Sound Issues (1/25/17) – Board booted and played, but only the crash sound was running, nothing else.  Outputs at 74LS273 at 1P didn’t look right, replaced it, but no change.  I should have spent more time looking at inputs, after further digging found that outputs at 74LS158 which eventually feeds 1P were dead. Replacing 74LS158 at 1P fixed the problem.

Garbage on Boot (1/23/17) – Not much sign of life, a few sockets were replaced at some point.  Burned new set of roms, installed them and board worked.

Rom 2 Error (9/24/15) – Reported Rom 2 error on boot, used Fluke to confirm rom was bad (it was) and replaced the rom. Board then reported ram “0H” error and failed ram test at 8000-83FF with Fluke which pointed me to 2114 at 6A based on my notes. Replaced 6A and board now works.

Garbage on Boot (9/24/15) – Immediately noticed Ram 6A socket was missing plastic piece, so I replaced and installed a 2114 ram, but no change.  Connected board to Fluke 9010a to test roms and ram and the board came right up. Installed another Z-80 and the board worked fine, so the original Z-80 was bad.

Rom OK Messsage (9/24/15) – Board wouldn’t pass self test. Top board known to be good, used Fluke to test Roms, all of them checked out okay (figured they’d would).  Put game in test mode and it reported bad OH ram, which led me to replace 6A.  Board now passed self test but played with color issues and some graphic issues.  Started pushing on ribbon cables and it would clear up a little, but not completely.  Replaced original cables with SCSI cables and board works fine.

Rom 1 – Rom OK Flashing (2/18/14) – figured this was a dodgy socket or bad mask rom.  First, I replaced all the mask roms as well as a few sockets that looked suspect.  Board booted with Rom OK message, put game in test mode and it reported bad “Rom 5H”.  According to the manual this is a 2114 at location 6E, which I replaced but continued to get the same message. Starting swapping out other 2114 rams and found that 6E was in fact the culprit.  Board booted right up now and works fine.

Graphics Color Issues (3/3/14)  - Game booted and played, but colors were off, car was red, just everything was off on colors and some graphics.  Bad prom at 11N was bad.

Quite a Few Konami Classic Board Repairs

Updated: Added Tutankham Sound Board Repair (3/7/17)

Had a free day today and spent some time digging out some Konami boards from the dead pile.  Make some good progress, nothing extremely complex, but always good to get some boards running again. I will update this page as I fix other Konami boards. Here's some of the highlights:

Circus Charlie, Bad ram on boot – Very clean boardset that reported “Ram Bad” when powered on.  Checked manual, but no reference to what ram it is referring to.  

I started by replacing 2128 ram at 3E just for the heck of it, but no change.  There are two more 2128 rams and 2114 rams, moved on to 2114 rams at 2F and 3F, checked the outputs with logic probe and they were dead.  Replaced 3F first, no change, replaced 2F and board booted and played perfectly.  Rechecked both of the 2114 rams that I removed and they were both bad.

Hyper Sports, video issues - Board had noticeable video issues, background was mostly gray, some game play could be seen, but it looked pretty far off.  Starting by reseating roms, found sockets at A12 and A14 to be bad.  Replacing those got board much closer, some sprites had vertical lines, starting by replacing rom sockets at G17, G18, and J17.  Video improved, finally left with one character on the vault stage that had vertical lines, which was due to a bad socket at J19.

Hyper Sports, marked as "touchy" - Board was tagged as OK, but touchy.  Tested it and pressing on the ribbon cable would get it to boot sometimes.  Replaced the ribbon cable, but no change. replaced the bottom connector for the ribbon cable, but no change.  Started pressing on ICs as it was booting and noticed one of the custom ICs was the cause. Removed it, cleaned pins and reseated it to solve the problem.

Hyper Sports, graphic issues - Board had vertical lines on some screens (but not all). Starting pulling socketed chips, they were very clean, just reseated them all and the problem went away.

UPDATE: board didn’t survive burn-in, problem reappeared, found socket at 12C to be bad by pressing on roms when game was on.

Pooyan, Board marked as has graphic issues, had no sound as well.

  1. Pulled custom ICs on the CPU boardset, cleaned legs, reseated them and the video issue was gone.
  2. No Sound, but some amp “buzz”.
  3. Reset line on sound board was stuck low, replaced 74LS02 at D7 and it was high again (more on this later).
  4. Still no sound, removed Z-80 (it was soldered on), installed socket, known working Z-80, no change.
  5. Tried another set of sound roms, no change.
  6. At this point I should have pulled the Fluke 9010a out to test stuff, but removed 2114 rams, installed sockets and tested them, all OK.
  7. Again, should have pulled 9010a out, but replaced a couple more ICs near Z80 thinking it would solve the problem, didn’t really feel like “thinking” today.
  8. Finally pulled Fluke 9010a out, ran Bus test on it reported a CTL Error. 
  9. After poking around for way too long, finally realized I installed a 74LS20 instead of a 74LS02 at D7.
  10. Installed correct 74LS02 at D7 and the sound came back.
  11. Lesson learned: Don’t fix arcade boards after playing two late night hockey games the night before and not getting enough sleep.

Scramble, no sound - Clean boardset, played, but no sound, sometimes a very low pulse or something like it was trying.  Started by swapped out processor and roms and then AY-3-8910s into a working boardset.  Found a bad AY-3-8910 at 3D.  Replaced this and the sound came up but was low. Replaced a couple electrolytic caps in the sound section just in case, but no change.  Noticed that pressing on op-amp at 3A would cause some buzzing and a bump in sound. Found a parts sound board and grabbed another op-amp which fixed the problem.

Scramble, no sound – Very clean boardset tagged as having no sound and “amp broke”.  Sure enough the amplifer was physically broken, grabbed another one from parts board and the sound came back.

Tazz-Mania, CPU Board boots to garbage (2/8/17) – Boardset was tagged as having Rom 2E Error.  Pushing firmly on Z-80 would sometimes get it to show a Rom error, 2E or 2H.  Replaced Z-80 socket and the board would boot now, sometimes come and play with graphic issues, other times Rom Error.  Replaced sockets for Roms at 2C, 2E and 2H and board booted with graphic issues. Pressing on rom at 5F would make things change, replaced socket at 5F and board worked perfectly.  Let it run for two days just in case any other sockets were bad, but seems to be very happy now.

Time Pilot, distorted graphics – Board was working, but in testing developed some distorted graphics, but still played. Starting pressing on custom chips and found IC4 at F12 to have dirty legs.  Cleaned the legs, the problem persisted so I replaced the socket and the problem was fixed.

Track and Field, No Sound (3/3/17) – No sound at all, no amp buzz, suspected a bad amplifier. Recapped sound section and replaced amp, still no sound.   Started checked sound CPU, signals looked good, used scope to see if the board was making sounds before the amp and it appeared to be behaving normally.  I replaced the LM324, LM358 and 4066 ICs in sound section as I wasn’t sure what else to do, but no change. 

Still no change, pulled the amp I installed and noticed it was a LA4460 as indicated in the manual, BUT the board had a LA4461 amp installed, which uses the same pinout, but in reverse. Removed LA4460 and installed it “backwards” and the sound came back. Wish I would have looked closer at the amp I removed, I assumed it was LA4460 as that is what is in the manual. 

Tutankham Sound Board, no Sound (3/7/17) – Removed, checked and socketed Z-80 processor to further troubleshoot with Fluke 9010a. Z-80 and 2114 rams checked out. Rom 7A did not verify with 9010a, grabbed another, but still did not verify. Pressing firmly on it and the sound came back. Replaced rom socket at 7A to fix the problem.

Tutankham, horizontal lines - Video board had lines on boot-up.  Suspected a bad 4116 ram, just wasn't sure which one.  Started replacing a couple and finally spent some time with a logic probe looking at outputs and found two that seemed to be different than the other rams. Replaced these two and board booted.

Yie Ar Kung Fu, graphic issues - Booted with blocks around some graphics.  Started swapping the graphic roms (don't remember location off the top of my head) with a known working board.  All checked out okay. Reinstalled and powered non-working board back up and it worked.  Apparently one rom wasn't seated well or making good contact.

Taito's Qix Hardware and Games (Zoo Keeper, Kram, Electric Yo-Yo, Space Dungeon, Complex X)

Last Updated: 2/3/17 - Added a Video Processor and Sound Board repair.

I’ve always been intrigued by Taito’s games running on Qix hardware. Zoo Keeper is one of the best classic games out there and over the years I’ve spent way too much time researching these games messing with these boards, getting to learn a bit about them. 

While Qix and Zoo Keeper were two of Taito’s most popular classic games, Taito also released other games on the hardware, including Electric Yo-Yo, Kram, Space Dungeon and Complex X.  In my years of collecting I’ve owned all but Kram and Complex X. 

I don’t know production numbers but can say from experience (I’ve been collecting games since the late 90s) that Qix and Zoo Keeper are by the far the most common games, Taito probably made more Qixs than any other game as those are the boards I’ve come across the most.  Based on what I’ve seen Zoo Keeper’s production run was fairly high as well, but nowhere near as high as many of the classic arcade games you'll find, I’d probably consider it uncommon.

I have personally owned three Space Dungeons and seen a couple for sale over the last 20 years or so, I would consider it the third most common, but something I’d still classify as rare.  I’ve owned on Electric Yo-Yo and have seen maybe one or two other on the market in the same time.  I have only seen one (maybe two) Kram pop up for sale in the past and would say they are even harder to find that Space Dungeon. At one point I found a NOS Kram control panel overlay as well (I sold it while back). I do own a Kram bezel but it has seen much better days. I have never seen any Complex X games, only heard of a header and manual being found.

Space Dungeon running on a Taito test rig.

Space Dungeon Running on my Qix Test Rig

I’ve written this document to help other collectors preserve and learn more about these games and the boards that are needed to keep them going. 

Quick disclaimer: I have had pretty good success fixing these boards and converting them to the uncommon games over the years.  However if you don't know what you're doing in regards to soldering and working on arcade games find someone who does as you can make things worse.

Finally, this document is a work in progress, I plan to add quite a bit to it as I find the time, but I wanted to get some of this information out there.

Hardware Background

All of these games pretty much use the same boardsets, there are some minor differences but those are all related to Zoo Keeper (I can’t speak for Complex X as I haven’t had that running yet, but do plan to do one day).  I use Qix as a starting point as that was the first game released. Qix includes a Video Processor Board, Data / Sound Board and Rom I/O boardset. 

All later games include these boards as well as a Coin Processor Board.  Zoo Keeper includes one extra board, a Rom Expansion Board.  You can pretty much take a Qix boardset and convert it to any of these games.  You do need the Rom Expansion Board to make a Zoo Keeper boardset, there were reproductions of this board out there last I checked.

The Taito manuals are very good at explaining how these boards function and other details (good schematics, how to run test mode, etc.) so I won’t go into too much detail on each boardset, but here is a quick rundown and some other useful tips:

Video Processor – The largest board in the boardset, it mounts on the top of the metal frame and is probably the most common one to fail or not work when you find it in a game.  According to the manual this board, “performs all screen based functions, such as playfield image motion, line drawing, etc”.

Taito Video Processor Board used in all of these games

This boardset includes one of the 6809 processors (the game uses two to run) as well as two 2114 program rams, 32 4116 video rams and two 2148 rams, among other components.

The most common problem with these boards is that the battery originally mounted leaks corrosive acid which eats up traces and ICs on the boardset.  If you find a “clean” video processor boardset, you’ll have a much easier time getting it run as most other problems are related to the tantalum caps and 4116 rams which are all socketed.

Interesting side note, Slither uses the same video processor boardset as these Taito games, although it is labeled by Century II Corporation. I have personally tested one of these on my test rig and it works fine.  Slither uses a DSR (Data/Sound/Roms) which is different that Taito’s setup.

Century II Video Processor Board from Slither (will work in Taito games though).

Rom I/O – This is the middle board in the set and contains the game’s Program Roms for both the Data, Video and Sound Processors.  This board also includes three 6821 PIAs used to control the coin door and player inputs.  These boards are fairly reliable, assuming no corrosion got to them from the battery on the Video Processor boardset.  I have seen sockets go bad on these and occasionally a 74LS138 used to select the roms. 

Qix Rom / IO Board

The 6821 PIAs do fail from time to time, in which case your inputs will not work properly.  On the earlier versions of these boards they are soldered directly to the board, later versions they were socketed.

Data / Sound Processor – The bottom board used in the boardset and performs two functions, the Data Processor, “which supervises the operation of the entire system” and the Sound Procesor, “which generates sounds under the direct control of the Data Processor”.

Qix Data / Sound Processor Board

Again I find these boards to be pretty reliable, a good chunk of the ones I’ve found work right away, some have had bad 2114 ram or sockets as well as bad processors 6809 for the data side or a 6802 for the sound side.  I have come across a bad amplifier or cap as well related to sound issues in the past.

There are two versions of the Data / Sound Processor, Qix’s board is fully populated (except for U19) while Zoo Keeper used a boardset what didn’t include certain components on the bottom left hand corner of the boardset, include the J9 connector, U21, U25, U22 , SW1 and U26, among other components. 

Zoo Keeper Data / Sound Processor Board (note the empty area on the bottom left hand side).

They are pretty easy to tell apart when side by side.  Note that you can convert Qix Data / Sound boards to Zoo Keeper, the procedure is as follows:

1. Cut trace between TP-5 and U17 pin 6 on the component side

2. Cut trace between U23 pin 13 and feed through hole on solder side.

3. Wire Tp-5 to U23 Pin 13.

4. Wire U17 pin 6 to U23 pin 12

I believe all of the other Taito games (Space Dungeon, Electric Yo-Yo and Kram) use the Qix Data/ Sound board.

Coin Processor – Since all of these games share the same hardware, Taito added a Coin Processor board to all games (except for Qix as it was the first released) to prevent operators from converting one game to another.  Luckily, there is a coin processor bypass rom available for games, which allows you to eliminate the Coin Processor and basically convert Qix boards to any other game out there. 

My Game is Broken. How Do I Fix It?

Probably why you found this article in the first place was to figure out how to fix your Qix or Zoo Keeper. My first word of advice is to be patient, these boards and games can be overwhelming, especially if you don’t have much experience with classic arcade games.  They are probably not a good first choice for a novice, but I’ll do my best to provide some repair tips.

Assuming your monitor is known working, the first thing to suspect is your power supply, the Taito Linear power suppliers are notorious for failing. I highly recommend installing a switching power supply kit sold by Arcadeshop. It replaces the old power supply with a modern power supply and includes a reset circuit board which is needed to have these boards boot-up. 

First check that you have the proper voltages on the boardset (be sure to measure for +5VDC, +12VDC and -5VDC as all of them are used on these boards). Next step is to see what the game does on boot-up, assuming it doesn’t fully boot take a look at the LEDs on the Video Processor board as they may tell you what is wrong.  The manual will walk you through the self test procedure and hopefully point you to a failing IC. I won’t go into too much detail, but will say this isn’t always 100%, it cannot detect every error or problem.

If you don’t get anywhere with the self-test procedure I would do the following, these are things I pretty much to do every boardset I work on and it addresses quite a bit of problems with them:

  1. Check your ribbon cables, reseat them, cross your fingers, ideally just replace them with a new set if possible as they can cause so many problems. I can't emphasize this enough, I've had boards run fine and then not boot 10 minutes later due to touchy ribbon cables.
  2. Check factory jumper wires on the board to be sure they are in place.
  3. Carefully reflow solder joints on header pins on all of the boards.
  4. Check reset circuit, try powering board up a few times. Some seem more touchy with regards to booting and the reset circuit setup.
  5. Replace all 10uf 25V tantalum caps near 4116 rams with electrolytic caps on Video Processor board.
  6. Replace all 4116 ram chips on Video Processor board
  7. Replace 2114 sockets at U3 and U4 on Video Processor board

Rom I/O Board Info

I’ve mentioned all of the Rom boards are the same for all games, Qix Rom boards were shipped with jumper packs for 2716 roms (which Qix uses), most other games use 2732 roms and need 2732 jumper packs, I’ll get to this eventually.  There are multiple rom versions for Qix, I have not seen multiple rom versions for the other Taito games.  I’ve seen Qix boards with at least three different rom set versions:

QQ Rom Set 1 – Consists of 16, 2716 roms at U3 through U19 and one sound rom at U27, all roms are labeled QQ3, QQ4, etc.  For some reason these boards almost never seem to work for me. I’ve seen a bit of these boards in my time.

Qix Rom / IO Board with QQ Rom Set 1 Roms Installed

QQ Rom Set 2 - Consists of 16, 2716 roms at U3 through U19 and one sound rom at U27, all roms are labeled “QQ3 -02”, “QQ4 -02”, etc.  This rom set is common.

Qix Rom / IO Board with QQ Rom Set 2 Roms Installed

QU Rom Set 1 - Consists of 14, 2716 roms at U3 through U19 (except for U6 and U15, they are empty) and one sound rom at U27, all roms are labeled “QU3”, “QU4”, etc. with handwritten labels. This rom set seems to be uncommon. 

Qix Rom / IO Board with QU Rom Set Roms Installed

Qix II: Tournament Rom Set - Don't have one handy, but I've seen this running on some Qix Rom boards as well.  

For some reason almost every board I have with QQ Rom Set 1 does not run on my test rig, I have no idea why, if anybody has some insight let me know.

The biggest issue I've had with rom boards are bad roms and bad rom sockets.  If you're rom board is bad I'd start by pulling and checking the roms, and then move onto the rom sockets and the 74LS138 ICs on the boards. If you're looking enough to have a Fluke 9010a and 6809 pod you can use it test the rom signatures: roms U3 to U10 using 6809 on the Video Board and roms U12 to U19 using the 6809 on the Data / Sound Board.  

There really isn't much else to look at.  Before doing anything check the board for signs of corrosion, I've seen many of these boards with bad traces and sockets from the battery on Video Processor leaking acid on them.  Sometimes they aren't worth the effort to fix if they are badly corroded.  

I would also recommend reflowing the solder joints on the header pins, especially at J11 as that is the power input to the board.  The joints are usually okay on these boards, but it is good preventative maintenance.

If you're having an input issue (start buttons, joystick, buttons or test mode buttons not working), check the 6821 PIA chips on the rom board, there are three of them, the schematics show you which inputs they control.  The 6821 PIA chips are soldered on some boards and socketed on others.

If your having a sound issue and you're certain it is NOT the Data/Sound board, U27 (and U26 on some games) are the sound roms, check those roms as well as the sockets.  

Repair Logs

I've fixed quite a few of these over the years, will add to this list as I have the time and fix some more.  Here goes:

Video Processor Boards

Dead, Nothing on Screen (2/3/17) – This was a board I had repaired for someone, came back to me as not working.  It was dead on boot, all LEDs on, replaced processor socket just for the heck of it.  Used Fluke 9010a to try to test roms, but none were testing properly.  The buffer ICs looked good, noticed some corrosion on the legs of 74LS08 at U101, it wasn’t horrible, but enough to make me want to replace the IC.  Replaced U101 and board booted again and now works.

Dead, Nothing on Screen (1/8/17) – Board didn’t show much signs of life, but hit the test switch and LEDs responded and indicated a bard CMOS ram at U85 or U86.  Tested them in a good board and U86 was bad.  Board now booted with a video issue. Ran self test it reported bad 4116 ram at U26. Pulled it, one leg was out of socket, reseated it and board worked. Replaced tantalum caps near 4116 rams as preventative maintenance and ran board overnight without any issues.

Dead, Nothing on Screen, All LEDs Lit (12/15/16) – This board had no corrosion, but was bounced around a bit as both of the 50 pin connectors had broken and bent pins and it was missing its 2114 rams.  Since the traces were very clean I decided to spend a bit of time rebuilding it, replaced both of the 50 pin connectors (J3 and J6) as well the 2114 ram sockets (u3 and U4) and 6148 ram sockets (U56 and U57).  I also replaced the 6809 socket (U82) and 6845 socket (U18).  Both of those sockets were falling apart as I removed them, the legs were breaking off once I removed some solder, so it was a good call replacing them.  I also gave the board a quick bath and scrub down.

After replacing all of the above, I was optimistic it would be close to working, but it booted with all LEDs on and nothing on screen.  Poking around I noticed the clock signals were missing on the 6809 (pins 34 and 35).  Worked my way backwards and thought the problem was 74LS74 at U36, replaced this but no change.  More poking and I noticed U36, pin 12 was stuck low and shorted to ground on the board.  Traced this back to the large connector that I replaced at J6, pin 27.  When I replaced this connector I shorted this pin to the ground pin right next to it.  Visually it looked fine, but there must have been some solder shorting it out. Removed the solder on those connectors, resoldered and the short went away.

Board now booted with a minor video issue which I found to be a bad 4116 at U30 by using the game’s self test procedure. Replaced the bad ram and board is now working. Will probably hang on to this one for my test board due to the amount of time I have in to it. Always nice knowing having a reliable, rebuilt test board to work from.

Rom Boards

Zoo Keeper Rom, Sound Issue (1/18/17) – Board would spit out some garbled sounds, but definitely not right.  Pulled sound roms, all tested okay in working boardset.  Replaced 74LS138 at U28 since there is much else in the circuit driving sound and sounds came back.  Guess it could have been rom sockets, but all of the other roms had original sockets and the board was otherwise working.

Qix Rom, No Sound (1/11/17) - Board booted up and played fine but no sounds. Pulled the sound rom at U27, tested fine in my rom burner. Swapped the rom in a known working board and I had no sound.  I've seen roms do this a couple times before test fine in my burner but not work in a board, can't really explain this one, but it happens.  Burned new U27 rom to fix the board.

Zoo Keeper Rom, Sound Issue (12/20/16) – Originally thought this was a bad Data/Sound board, as it would just spit out a beep or two, some static and then sound would cut out.  Turned out jumper pack at U29 for sound roms was loose.  Would hold it down and sound would come back.  Replaced socket with machine pin sockets as I was using a custom made jumper pack that wasn’t making the best contact with the original socket.

Qix Rom, Boots to Initial Screen with Languages, but that’s it (12/9/16) – This board seemed closed, would boot to first test setup screen but not go to attract mode.  Ran self test and it gave an error at the U8 rom.  Pulled the rom, it had some corrosion and the socket was corroded. Remove the socket, cleaned up the corrosion, installed new socket and new U8 rom and the board booted fine.

Zoo Keeper, No sound (9/29/14) – Board played fine, but no sound. Pushed hard on rom U27 and the sound came back on. Rom socket solder joints looked iffy, but I just replaced entire socket to fix the problem.

Zoo Keeper, Nothing on Boot (9/29/14) – Board was marked as okay and roms tested okay. Noticed that when I messed with U22 I’d get signs of booting so I replaced that socket, but no change. Replaced 74LS138 at U21 and that fixed most of the problems.  Game came up and played, but would not completely cycle through test mode.  Swapped 6821 PIA at U11 and that solved the problem.

Zoo Keeper, Nothing on Boot (1/30/12) – Board would do nothing on boot-up.  After a quick glance, the jumper packs were installed backwards.  Fixed the jumper pack orientation and the board would boot but in game mode I would only get some stair graphics.  Put board in test mode and it reported a bad rom Z13.  Replaced the rom and the board worked.

Zoo Keeper, Nothing on Boot (12/12/11) – Board would not boot, other boards known good in set.  Tested all of the roms, they were okay, but still no boot. Also tested the jumper chips and they were all fine.  Was real puzzled here, tried the roms in another board just to be sure, and they were fine.  Finally started pushing real hard on the roms and trying to reset board and it came up.  Started replacing rom sockets, about 4 of them were touchy, one was very corroded.  Kind of odd since there was no corrosion signs on the board itself or traces.  Board now booted up but wound up locking up after 10 minutes…

Tried to power it back on and it didn’t come back up. Checked continuity on rom legs and everything was fine.  Checked 74LS138 chip at U2 and noticed the outputs were not correct compared to working a board.  Checked the inputs and they seemed okay. Replaced U2 and the board came up just fine.

Sound / Data Boards

Nothing on Power-Up (2/3/17) – Quick inspection showed that 74LS244 at U1was removed at some point (probably for parts).  Installed new socket and 74LS244 and board booted, but no sound.  Further inspection showed that someone started remove 74LS244 at U12 (guess they gave up and removed U1 instead).  Finished removing it, installed s new socket and another 74LS244 and sounds came back with a minor issue.  

Sound issue was tough to describe, certain sound patterns had a “click”, just something was off, if you didn’t know the game you probably wouldn’t have noticed it.  Replaced a few ICs (U20, U24) but no change, initially my gut told me this was something else (not a bad IC), but tried replacing those chips anyway.  Compared board to another board and noticed C44 was missing, but clearly the board was shipped without it from the factory.  Dug out some other boards and they had C44 installed.  Installed 1uf 50v cap at C44 and the problem was fixed.  Not sure if this was an early board that didn’t have installed or it was just never installed by mistake.

Powered on, locked up almost immediately, initial setup screen issue (1/18/17) – Clean sound board that came up, but at the “This Location” screen the first character was constantly changing, almost like a test switch is toggling.  After going into game mode, board would lock up almost immediately.  Replaced the sockets at 2114 for preventative maintenance, tested 2114 rams, they were okay.  Tested 6809E and it caused the same problem in a working boardset. Replaced 6809E and board is now working.

Sounds would also drop out after a while, sometimes 5 minutes, sometimes 15 minutes.  Initially suspected a bad socket in sound circuit, replaced 6802 socket at U5, but no change. Also replaced socket for 6821 at U7, still not change. Noticed when I pulled U7 with board running, sounds would come back.  Replaced 6821 to fix the problem.

Working, but Sound Would Cut or Not Work sometimes (12/12/16) – Board worked just fine sometimes, other times no sound, sometimes it would cut out after 5 minutes or so.  Replaced the 6802 socket at U5.

Nothing on power on (9/29/14) – Quick visual showed a bent pin on 6809, which I straightened out to fix the problem.

How to Convert your Qix Boards to Another Game

You can fairly easily convert any Qix boardset to EYY, Kram or Space Dungeon by burning a new set of roms and replacing the jumper packs at U1 and U22 on the Rom / IO board.  You’ll need a 12 blank 2732 roms, a blank 2716 and a rom burner in addition to 14 pin sockets to make the jumper packs. Here's a quick summary of the games and what roms they use:

When converting boards from Qix to other games that use 2732 roms, make sure you change the jumper pack at U1 and U22 (and U29 if that game uses 2732 roms  for the sound (U26 and/or U27, Zoo Keeper only).  You can make these jumper packs by hand using 14 pin machine tooled sockets and some light weight wire or thin metal (cuttings from caps work very well for this).  

Just run your jumper leads from pin 2 to pin 14, pin 3 to pin 13, pin 4 to pin 12, pin 5 to pin 11 and pin 6 to pin 10. I use a dab of solder on each pin to hold the jumper in place.  Here’s a visual of what it should look like:

Also make sure you use the coin bypass rom (U14 for all games, I believe).  Space Dungeon will boot without the coin bypass rom and is playable but reverts to the test mode after a game (don’t ask me how I know that). Once you have your new roms burned and jumper packs installed the board should work.

Hopefully this will get closer or up and running.  Eventually I will add some more repair tips, just out of time right now.  Some upcoming topics I’ll be also be adding:

How to Save your Scores

How to Build a Qix/ZK Test Rig

How to Play Zookeeper Like a Pro