Wizard of Wor Issues

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I bought a non-working Wizard of Wor a couple of weeks ago that was DOA. I rebuilt the 90411 power supply with a Bob Roberts kit and now the game will boot, however I've got some graphics glitches on the game. The game is fully playable, but I'm wondering if this is an indication of bad RAM, game ROMS, or power. After rebuilding the power supply I'm able to adjust the +12 & -5 voltages, but the +5 is stuck at 4.85V no matter how I adjust the pot. I attempted to use the test switch to get into the diagnostics menu to check the RAM / ROMS, but all it will do is display the rug pattern below. Any ideas?
 

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Please post your progress. I just got a Wizard of Wor and have not had a chance to mess with it. I suspect a bad power supply to start with but anticipate more serious problems.
 
Your first picture looks like a RAM issue......but you also need to address the power issue. Was the 4.85 measurment at the power supply board or at the motherboard cage? If you had 4.85 at the power supply board....it's probably even less by the time it gets to the motherboard. That can cause issues.

Edward
 
The 4.85V is at the edge connector of the power supply so I'm sure it's even less at the PCB. Unfortunately there's not an easy way to test the voltages at the cage. Before I rebuilt the power supply it appeared that the previous owner had attempted the Bob Roberts 90411 rebuilt kit and failed miserably. The 4700uf, 2200uf, and 470uf caps were installed backwards and it blew two 1N4007 diodes at D12 & D13. The guy also lifted a few traces while doing his hack job, so my rebuild was a bit of a challenge. At this point I'm not sure why I can't adjust the +5V now that it's rebuilt. None of the existing resistors or diodes that weren't included in Bob's kit appear to be damaged on the board. Any help would be appreciated or if someone's got a working 90411 that their willing to sell I'd be interested.

On a side note I just got done pulling all the PCBs, and cleaning and resocketing the ICs. No change in the game symptoms. I'm torn between this being a power problem and a bad RAM chip somewhere.
 
Power supply issue resolved. All voltages are now good, but I still have the graphics glitches. Does anyone on the forum repair WoW/Gorf boards?
 
Can anyone that owns a WoW tell me what sockets should be populated on the Memory Board. Mine has several empty sockets. Just wondering if I'm missing some chips. See the pic of mine below.
 

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I bought a non-working Wizard of Wor a couple of weeks ago that was DOA. I rebuilt the 90411 power supply with a Bob Roberts kit and now the game will boot, however I've got some graphics glitches on the game. After rebuilding the power supply I'm able to adjust the +12 & -5 voltages, but the +5 is stuck at 4.85V no matter how I adjust the pot. Any ideas?

If you might be interested, I have a tested working PCB set and a tested working power supply board available for sale. Check my FS posts if interested for prices and details.
 
You really really have to test the power on the actual game board. it's easier than you think. Most boards have filter capacitors on the edge of the card, just measure the voltage at the two legs of one of the electrolytic caps on the gameboard in the front of the cage. You also need to make sure that your edge connectors are all really clean for the same reason (power drops). If the game board isn't even booting and just has a rug pattern I would look at the cpu board first, and also look at the rom board. I think yours is complete, the extra sockets weren't used I don't believe.

Do you have a Gorf by any chance to swap boards with?
 
The game boots fine it just has some graphics glitches. The rug patter is displayed when I go into the test menu unfortunately some reason that's the only function I can access in the test menu. I don't have a Gorf to swap with and I'm also not seeing any capacitors on the first card in that cage to measure voltage across. I've also tried adjusting the 5V up, but it doesn't fix the lines on the screen or the white spots.
 
Can anyone that owns a WoW tell me what sockets should be populated on the Memory Board. Mine has several empty sockets. Just wondering if I'm missing some chips. See the pic of mine below.

You're missing RAM....2114 type....empty/smaller IC sockets should be populated.

Edward
 
That's correct. The same sockets are empty on all of mine.
 
Your problem (the yellow lines in the screen) is a failure of a chip on one of the RAM cards. They're the two smaller boards at the end of the stack, and are interchangeable with each other. Also, GORF uses the same RAM cards.

There's a test ROM on ionpool that Spaeth wrote, you can burn a copy of that and install it on your ROM board and it will help you determine which RAM chip has failed. They're a funny type, but I think Bob Roberts has them.

-Ian
 
Thanks, I've purchased another board set so I'll swap out the RAM cards one at a time and see what happens.


Your problem (the yellow lines in the screen) is a failure of a chip on one of the RAM cards. They're the two smaller boards at the end of the stack, and are interchangeable with each other. Also, GORF uses the same RAM cards.

There's a test ROM on ionpool that Spaeth wrote, you can burn a copy of that and install it on your ROM board and it will help you determine which RAM chip has failed. They're a funny type, but I think Bob Roberts has them.

-Ian
 
Problem solved I've gotten rid of the yellow bars. It was indeed an issue with one of the RAM cards. Is there an easy way to determine which RAM chip is bad or does that require some type of logic probe?
 

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Is there an easy way to determine which RAM chip is bad or does that require some type of logic probe?

Yes, there is an easy way. There is a wonderful test ROM that Spaeth wrote a long time ago, it's up on ionpool. Burn that, and install it in your ROM board, and you can determine which chip is bad.

Edit: Correction. Commander Dave wrote the Wizard of Wor ROM and the original GORF test ROM, Spaeth wrote the updated GORF ROM. I don't know if Spaeth's GORF ROM will work in Wizard of Wor - the games are similar, but not identical.

-Ian
 
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Problem solved I've gotten rid of the yellow bars. It was indeed an issue with one of the RAM cards. Is there an easy way to determine which RAM chip is bad or does that require some type of logic probe?


Could you point me in the direction of where you purchased your RAM cards? I recently acquired a WoW game that worked initially with some staticy lines at the top and the bottom of the screen. Now the screen flipped vertically, and I have to shut it off to start a new game.
 
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