Had a sort of Super Saturday of my own yesterday, I repaired 3 Speccys including one (see earlier posts) that'd been bothering me for ages. I had removed it's Z80 so I could replace it with socket in order to later fit a Simple 8Bit IDE Interface, everything went well until I powered it up and I was greeted with a red or magenta border with alternate black & white bars and flashing attributes on the screen. After hours of detective work armed only with a multimeter I found a short between D6 and A2 which could well have destroyed either TR3 because when I finally got round to replacing it with a real ZTX313, problem solved!.
Next up was an Issue 3 board I got off Fleabay that was listed with a keyboard fault, the seller reckoned it was a ULA and I had a matching but untested replacement so I thought 'Ok, I'm in...'. I replaced the ULA and tested it with known working keyboard, still nothing from the keyboard so I asked those who know on WOS Forums who suggested I replace TR6. One replacement ZTX313 later and bingo!, a working keyboard - thanks to WOSf members McLeod_Ideafix, Johan1973, RetroTechie, RoKo and Guesser for all your help.
But no... I was going for the hat-trick, an Issue 3 rubber keyboard model that I bid on before reading the description properly, untested, no membrane, knackered faceplate and no ULA!. I simply took the ULA I had just removed from the previous machine, pressed it into the socket and gritted my teeth as I powered it up. It works! - not had time to thoroughly test it yet but I have another broken rubber keyboard machine coming soon that should yield enough parts to get a working machine.
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