Couple of Konami Repair Logs - one easy, the other not

DarrenF

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Couple of Konami Repair Logs - one easy, the other not

Konami Rush'n'Attack
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Symptom: sound very & scratchy, doesn't really respond to volume pot
Thoughts: bad electrolytic caps in audio section
Action: replaced about 4 caps
Result: now responds to volume pot, but still very low & a bit scratchy
Thoughts: bad amp
Action: replaced LA4460
Result: audio now good

Konami Super Basketball
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Symptom: dead, no activity on CPU R/W line after several seconds
Diagnosis: logic probing shows some RAM not being activated, found bad address decoding
Action: replaced LS32 @ J22
Results: now sometimes boots to badly botched (extremely blocky) gfx, but recognizable action (sometimes boots to solid screen)
Thoughts: bad EPROMs?
Action: pull and verify EPROMs
Results: all OK; no help
Thoughts: must be something bad in the (huge) gfx section
Diagnosis: found a bad logic chip in tile gfx section w/logic probe
Action: replaced LS86 @ E17
Results: gfx slightly improved (more horiz resolution present); still sometimes boots to solid screen
Diagnosis: found two bad more TTL ICs in tile gfx section with logic probe
Action: replaced LS86 @ F20 & LS273 @ E19
Results: tile gfx now fixed; sprites totally missing; still sometimes boots to solid screen
Diagnosis: problem in sprite section, duh... found no activity on RAS line of sprite RAMs
Action: replaced LS153 @ A17
Results: sprites now present, but messed up; only in 2nd and 4th horizontal quadrants of screen (the indeterminant state of the RAS line on the RAMs must have been causing the "blank screen" sometimes when it booted... which was the sprite hardware covering all the other gfx)
Diagnosis: sonofabitch, are you kidding me? much logic probing ensured...
Action: found and replaced questionable LS161 @ C15 (one output just didn't "look right" compared to the others)
Results: sprites fixed! Appears 100% now.

7 bad ICs?!? I'm just glad the customs were all good...
 
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BTW, I found an error in the Super Basketball schematics:

In the lower-right corner of the CPU board (just left of the title block); the input to the LS17 @ B17 is labeled as RES/ (as in the reset line). It IS NOT the reset line, it is actually the RAS/ line (as in row address strobe). It originates in the clock circuit on the left side of the schems.

Darren
 
Nice job on the repairs Darren! Let me know if you need more damaged boards, I've got a stack of them I can send you! :-D
 
Let me know if you need more damaged boards, I've got a stack of them I can send you! :-D

I'm presently working thru a box that came from a local friend...

Depending on what sort of thing is in your box, we may be able to work out some sort of arrangment :)
 
Turns out I wasn't done with these. They worked fine on my test setup... but it lacks a full set of controls (all I can currently do is jumper the edge connector to 'press' buttons). So when I got around to building a Konami/JAMMA adapter and trying these in a cabinet, I discovered some more issues with both of them...

Konami Rush'n'Attack
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Symptom: coins up, starts 2PL game, but not 1PL game; some dip settings also don't work
Thoughts: bad input multiplexer
Action: studied schems then replaced LS253s @ 1E & 2D
Result: all buttons and dips now working properly

Konami Super Basketball
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Symptom: "pass" button doesn't work
Diagnosis: bad input multiplexer
Action: replaced LS253 @ 4E
Results: pass button now works

Symptom: sound frequently hangs or stops
Diagnosis: something with the CPU side of the sound board :)
Action: reseated sound EPROMs
Results: sound now works fine for extended soak test

Hopefully I'm done with these damn things now...

EDIT: BTW, all of the bad LS253s were Fujitsu...
 
Eight + bad chips on a Konami Super Basketball....Ugg!
I'd of probably stopped after bad chip #1:D

Nice work/logs!

Edward
 
Turns out I wasn't done with these. They worked fine on my test setup... but it lacks a full set of controls (all I can currently do is jumper the edge connector to 'press' buttons). So when I got around to building a Konami/JAMMA adapter and trying these in a cabinet, I discovered some more issues with both of them...

I did almost the same thing recently. I was repairing a Pac-Man board that I thought I had working 100%. Until I remembered to test it in cocktail mode. I thought, "What are the chances cocktail mode doesn't work if upright mode works perfectly?" but tested it anyway. Sure enough, the game would consistently reset as soon as the screen flipped for Player 2's turn. I fixed it, but that was a good reminder to always test all the game's options. Never give a game PCB the benefit of the doubt. ;)
 
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