Introduction I recently received a nonworking Atari 800XL that would boot straight to the built-in RAM test instead of the Ready prompt. It failed the RAM test almost completely with a grade of âFâ. I discovered when I cracked it open that it was loaded with cheap Micron Technology (MT) DRAM 64Kx1 RAM chips
Read postCase Studies in Retro Computing Repair #15: Diagnosing and Fixing the Crystal Clock Oscillator Circuit in an Atari 800XL
Introduction I friend brought me his Atari 800XL that was not generating any video signal. I confirmed with a multimeter that the chips were all getting good voltages. None of the chips were overly hot, and I confirmed with a working machine that they were all good. Case Study Given
Read postCase Studies in Retro Computer Repair #14: Diagnosing and Fixing a Faulty Non-Maskable Interrupt (NMI) Signal on an Atari 800XL
Introduction I recently received an Atari 800XL from a friend that was booting to a black screen. This required breaking out the oscilloscope to track down the problem. Case Study I started troubleshooting this computer by probing the pins of the 6502 with an oscilloscope after making sure all the chips were
Read postCase Studies in Retro Computer Repair #13: Fixing an Atari 800XL with a Stuck Key
Introduction I purchased this Atari 800XL locally. It was in decent condition and spruced up nicely after some scrubbing with 99% isopropyl alcohol (IPA). I did not know when I bought it whether it worked and was happy to see it boot right up to the Ready prompt with a
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