Upgraded Atari 800XL comes back butchered

A detailed deep-dive into an Atari 800XL I upgraded in March 2022 which has been sent back for repairs having been worked on by Piotr D. Kaczorowski, who installed extra parts in an attempt to 'stabilise' the system. The machine turns out to be a Pandora's Box of problems and surprises.

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00:00:00 Introduction and overview of problems
00:03:47 Motherboard inspection
00:08:45 Testing the audio cable
00:09:53 Cause of warping on the motherboard
00:12:00 New stereo jack and wiring
00:14:36 Testing the new stereo wiring
00:15:45 Further PokeyMAX troubleshooting
00:19:38 PokeyMAX problems revealed
00:25:30 An intriguing discovery
00:31:28 Sophia DVI connector and keyboard fix
00:39:12 Yet another problem
00:46:33 Original stability issues
00:49:36 Case lid fit solution
00:50:17 Reproducing COVOX problems
00:55:20 Another PokeyMAX wiring error
01:01:22 The correct U1MB plugins
01:04:57 SIDE 3 Loader COVOX player bug
01:14:48 SIDE 3 stability issues
01:15:31 Health problem roundup
01:17:49 Reproducing SIDE 3 stability issues
01:20:39 O2 fix and SIDE stability issue explained
01:27:21 Going one step further
01:31:56 Tentative conclusions on the O2 Fixer
01:34:27 More fault-finding
01:38:11 Summary and thanks

Soldering and test equipment:

● Hakko FX-951 T12 soldering station: https://uk.farnell.com/hakko/fx951-64...
● Best BST-863 hot air rework station: https://www.banggood.com/BEST-BST-863...
● Anesty (Duratool) ZD-915 thru-hole desoldering station: https://cpc.farnell.com/duratool/d006...
● Hanmatek DOS1102 dual-channel oscilloscope: https://www.amazon.co.uk/DOS1102-osci...
● Amtech NC-559 Tacky Flux: https://store.rossmanngroup.com/index...
● Goot Wick Desoldering Braid: https://store.rossmanngroup.com/index...
● Cynel Sn60Pb38Cu2 Tin/Lead Solder Wire: https://www.tme.eu/gb/details/lc60m2-...
● SysCheck v.2.2 by tf_hh: http://www.abbuc.de/component/jshoppi...

Equipment and software used for video production:

● Open Broadcaster Studio: https://obsproject.com/
● 2x Logitech Brio webcams: https://www.amazon.co.uk/Logitech-Gam...
● USB AV/s-video capture dongle: https://www.amazon.co.uk/Ex-Pro-Grabb...
● 135W Photography Studio Softbox Light: https://www.ebay.co.uk/itm/135W-Photo...
● Final Cut Pro
● Apple Motion
● 15" mid-2015 Apple Retina MacBook Pro

#atari
#retrocomputing