repair

 I still have my old copies of Texas Instruments' TLL Databook.  
Found these while surfing the web... very nice to have a copy of these on your laptop while debugging PCB's.

File attchments: 

LS_TTL-DataBook.pdf

Pocket TTL Book.pdf

 Well actually, it's a Punchout -> Donkey Kong -> Jamma adapter, but I'm too cheap to build a dedicated adapter just for Punchout.

 A friend and fellow arcade game collector asked me to look at a couple of his Tron PCBs.  This one kept resetting with random graphics and an occasional ROM error.

 No sooner did I take care of the graphic issues when an audio problem showed up.  Turns out he was getting speech and some audible effects but no background sounds or music.

John,  a friend of mine, asked me to take a look at his Punchout that was having graphics issues.