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Sunday, April 11, 2021

Quite a Few Konami Classic Board Repairs

Updated: Added Frogger Repair (3/7/21) and Tutankham Repairs (4/12/21)

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.

Frogger, No Sound (3/7/21)

  1. Clean board, played fine, no sound with volume pot connected.
  2. Swapped Z-80 and AY-8910, no change.
  3. Clock and reset line were fine on Z-80, there was activity on data and address lines on Z-80. Also activity on AY-8910 when sounds should have been playing, so I suspecting it was further down the line.
  4. Replaced LM741 for the heck of it as I’ve seen many op amps fail in the past. Sound now works.

The End, Video Board, Color issue in high score text (12/19/19)

  1. Color in the high score text was yellow and red mixed, not all red as it should be. Noticed that it booted solid red and then changed about a ½ second after boot.
  2. Suspected bad 2125 Ram as I’ve seen them cause similar issues in Galaxian boards.
  3. Swapped them all out, no change, swapped other socketed ICs just in case, but didn’t expect a change.
  4. After a bit of probing found the outputs at IC 15, 74LS32 to be low. Replaced this chip to fix the problem.

The End, CPU Board, Boots to garbage (12/19/19)

  1. Fairly clean board, swapped out Z-80 and started with 2114 Ram, found a bad 2114 Ram at IC25.
  2. Pressed on rom sockets and it showed signs of life.
  3. Pulled roms, cleaned legs and reseated, board boots and plays with sound but has video issues, lots of extra garbage on screen, but you can see and hear game playing behind video stuff.

  1. Suspected a bad trace from the video board, but couldn’t find one.
  2. Poked around the CPU board for a while, no luck.
  3. Noticed a scratch near the ribbon cable connector, very small, found one bad trace that was very close to connector and hard to find.
  4. Fix broken trace and video came back.

The End, CPU Board, Boots to garbage (12/19/19)

  1. Swapped boards, narrowed issue down to top CPU boardset.
  2. Pulled roms, Z-80 and 2114 working ram, all tested good in known working boardset.
  3. Replaced them and board would boot up and play, but was touchy.
  4. Spent too much time on this one, replaced a few factory jumpers that looked iffy (but not all of them).
  5. Was touchy near ribbon cable, replaced it and the 50-pin connector, but no change.
  6. Finally replaced one more factory jumper to fix the problem.

The End, CPU Board, Working, Sound Issue, then booted to garbage randomly. (12/19/19)

  1. This board was working with a sound issue, started booting to garbage randomly.
  2. Replaced factory jumper wire near edge connector to fix booting issue.
  3. Swapped sound roms, Z-80 and 2114 ram chip and found a bad 2114 ram chip at IC57.
  4. With good 2114 ram, still didn’t get proper sounds (would get some random noise sometimes).
  5. Probing around roms found address line AV8 stuck low also noticed data lines DV6 and DV7 were low.
  6.  Found bad 74LS08 at IC41 causing AV8 line to get low, replacing it brought it back to pulsing state.
  7. Two data lines were stuck low, quickly noticed that pin 21 of Z-80 was not in socket (my fault, rushing when swapping chips).
  8. Installed Z-80 properly and board had full sounds and music.

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.

Hyper Sports, was working, boots to "Qualify as DIP SW" - Clean boardset that came from a Track and Field game and was working one at one point. After bench testing it started acting up though.  Suspected a bad socket, found that when I pressed on the processor on the top board at E18 the board would boot. Replaced this socket and the board booted and played, but started acted up again with a similar error within a few minutes.  Started pressing on the roms on the same board and found another dicey socket at G9. Replaced that and the board booted right up and played with no issues. Not the first time I've seen suspect sockets on Hyper Sports boards.

Lost Tomb, No Sound (12/12/19) - Clean boardset, tagged as no sound.  Roms, processor and 2114 Rams tagged as okay. Turned pot and did hear some amp buzz, so didn't suspect amplifier. Started probing Z-80, rams and roms for activity, there was none, noticed pin 8 of 2114 was dead (not high or low, no signal). Traced back to 7404 at 4J, pin 11 was high, output at pin 10 was dead. Replaced 4J and sound came back to life.

Pooyan, Sprites had vertical lines in them

  1. Sold this board to a customer, arrived with a sprite issue, had vertical lines running through them.
  2. Socketed ICs on bottom board checked out okay (roms, custom ICs).
  3. Replaced 2149 at B11 as well as B8 and D12 but no change.
  4. Did some more probing and noticed outputs on 74LS163 at C10 were stuck high.  Replaced C10 to fix the problem.

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, Dead (1/8/19) - Very clean boardset, was surprised it wasn't working. Couldn't find me spare test board to swap out parts, but eventually came across an incomplete boardset months later.  Swapping out custom ICs, I found IC3 to be bad, installed another one and board works fine. It is always useful to have a spare working boardset set to swap from when fixing boards.

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. 

Sound Board, Spitting out Wrong Sounds, no Music (4/9/21)

  1. Suspected AY8910, replaced the one at F8, no change.  Thought maybe a bad 2114 ram as most sounds were there, just not synced up, but that turned out to be wrong logic.
  2. After replacing 2114 ram, no change. Replaced the other AY8910 at F7 and that fixed the problem.  Should have stuck with my first hunch.

Sound Board, no Music (4/8/21)

  1. Didn’t really feel like diagnosing this one, started by replacing AY8910 at F8 (which are soldered on this boards) on a whim as I suspected one of those to be the issue (roms were tested good).  Installed new socket and tested AY8910 and music now works.

CPU Board, Tagged as Lots of Horizontal Lines (4/8/21)

  1. Board I checked years ago, but didn’t spend too much time. Lots of horizontal lines, shorting 4116 output pin 14 and found that ram at 14A was causing sprite based lines. Replaced to fix it, but still had more lines going across screen.
  2. Replaced 4116 at 12A, line colors changed, but still present, shorting 11A and it got even better.
  3. Replaced 4116 at 11A to fix the issue.

CPU Board, Tagged as for Parts (4/8/21)

  1. Visual inspection showed 74LS240 at 2A was desoldered but still on board.  Removed it, installed new socket and new 74LS240.
  2. Board now boots up find with some graphic issues.
  3. Rom 71 had “bad chip” written on it, replaced, graphic issues improved, but still some artifacts
  4. Shorting pin 14 at 4116 and found artifacts disappeared when shorting 12A. Replaced 4116 ram at 12A to fix the problem.

CPU Board, Locks up, Graphic Issues (4/7/21)

  1. Seemed to be close to working. Reseating program roms got it running with graphics issues, lines and lots of garbage on playfield screen.
  2. Shorted outputs of 4116 at pin 14 to find the bad 4116, still plays with a lot of extra graphics on playfield.
  3. Stopped here…

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.

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