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PIcked up this game on 6/6/2015 at the NWPAS in Tacoma, WA. Game didn't have a monitor so I threw a spare K4901 in it, plays somewhat blind. Garbage on the screen but the sounds are all there like the game is actually running and playing normally, just can't make out anything on the screen. See sub-pages for power supply info and resource links. This game board has version 4 roms. There is a version 5 romset which is used in MAME and there is a freeplay mod available for the version 5 roms. I may update the roms to version 5 at some point to take advantage of the free play mod. The cab needs some love, marquee light is not hooked up, t-molding needs replaced, and cab needs painting/repairs. The marquee, control panel, and bezel are in mostly decent shape.

Initial suspect parts to look at:

    • Condor 5V power supply - tried adjusting voltage via pot and board went dead when I touched the pot, lost 5V from the Condor PS. Decided to order a new one since it's cheaper than a rebuild (~$30). New unit ordered and arrived 6/11/15. - Fixed

    • 2114 character gen ram on logic PCB @11C, 12C, 13C, 14C. - Fixed

    • Tantalum capacitors on the logic PCB (some damaged/missing) - Parts arrived 6/25/15 -Fixed

Repair Log:

    • 6/6/15 Installed spare monitor K4901

    • 6/6/15 Ordered replacement Condor 5v power supply off ebay - received 6/11/15

    • 6/12/15 Acquired a spare pcb (non-working) for parts/backup/repair reference

    • 6/19/15 The spare PCB didn't work (as expected) but it helped me narrow down a problem back to the Condor 5v power supply. It would fail under load and lose power, tested fine on the bench without a load.

    • 6/19/15 Installed the new Condor 5v power supply and the game is back to playing blind. All sounds and game play seem to be running fine.

    • 6/19/15 Hooked up monitor and game has garbled video but sounds like the game is running fine. Basically playing next to blind.

    • 6/20/15 Replaced 2114 character gen ram @11C, 12C, 13C, 14C.

    • 6/20/15 I hooked up a newer Vision Pro monitor and game video sync'd up. Only red color is showing so something wrong with color board and sync outputs of pcb (would not sync 100% on the 4901).

    • 6/22/15 I took the audio/color pcb from the spare set I bought on ebay (logic pcb non-working) and swapped it into the cab. All colors and sync are now present and game is working 100%.

    • 6/22/15 Hooked the K4901 back up and got it to sync, installed in cab and was able to play a few games. Next up - joystick rebuild!

    • 6/24/15 Loud humming sound started after being left on for several hours. Game would still play. Rebooted and screen showed audio board error at 3A/7A. Pushed the eproms in and issue went away.

    • 6/29/15 New T-molding received 3/4" black smooth. Will install at a later date after some cab restoration work is completed.

    • 6/29/15 Replaced the 4x4700uf 50v axial caps on the power supply board (preventive maintenance).

    • 7/1/15 Wired in the marquee light, bulb and starter were good!

    • 7/6/15 Spare board set had a bad volume pot that was shorting out, replaced with 10k audio pot.

    • 7/6/15 Burned a new Eprom at 13A for freeplay (version 4 rom). Freeplay works!

    • Next steps - Replace tantalum and electrolytic caps on both boards for preventive maintenance mainly, but a couple of the tantalums are missing entirely.

6/21/15 Current suspect parts for the original audio/color board based on missing green/blue/Hsync (all on audio/color PCB):

    • 74LS374 @11C, 12C, 13C

    • 74LS74 @10A

    • 74LS86 @11A, 12A

    • 74LS139 @9A

    • 74LS148 @10B

    • 74LS151 @11B, 12B, 13B

    • 74LS174 @13A

    • These are all of the parts used in the color and sync circuits of the audio/color pcb. Will probe these and use the piggyback method to narrow it down.

Note: The non-working boardset I bought on Ebay had a working audio/color pcb that I swapped into the cab. Colors and sync are good now. May repair the original audio/color board at a later time.

Old Condor Power Supply:

New Condor Power Supply - same model but newer production date:

Hooked up to a newer Vision Pro monitor game shows stable video, but missing green and blue. It wouldn't fully sync on the K4901.

Swapped in the audio/color board from the non-working set I bought on ebay. Fixed the colors/sync issue and now game is working 100%:

A couple more pics of the monitor installed and game running in the cab. Wells Gardner K4901:

Wired in the marquee light, the starter and bulb worked:

Here's the bad audio pot from the spare boardset before replacement. Note the pot is sitting at a tilted angle due to damage:

And here's the replacement pot, works great and no shorting/distortion. The replacement is a 10k 50vdc RadioShack #271-0282:

Here's the original Eprom at location 13A. Need to replace with freeplay version:

Freeplay rom was available (Thanks DogP!) at location 13A, burned a new 2732 for it and it works great: