Main channel: No schematics? No problem! Fixing a Leading Edge Model D (Patreon)

Published:

2024-07-19 00:33:58

Imported:

2024-07

Content

Hello my patrons! I'm trying to get back into the swing of things after being so sick. I'm still not fully up to speed yet, but let me try to get my feet wet with some bread-and-butter by doing a fun repair on this old Leading Edge Model D. This computer has some kind of video output problem, and since the video is on the motherboard it's not as simple as just swapping out the video card. Luckily, this machine is constructed with nearly all discreet logic, so while it looks daunting to think about a repair based on the number of ICs on the board, some logical thinking and the process of elimination helps narrow down exactly where the issue is. Join me in troubleshooting and figuring out exactly what is wrong with this system so I can bring it back to 100% operation. (If only I could be back to 100%!)

Thanks for all the support!

Direct link: https://www.youtube.com/watch?v=djNStzQhTx8

Files

No schematics? No problem! Fixing a Leading Edge Model D

This Leading Edge Model D has an issue on the video output which is built onto the motherboard. Let's use some logical reasoning and deduction to figure out exactly which chip is bad to get this machine up and running again. -- Links PC Archeology Leading Edge Model D: https://www.youtube.com/watch?v=mqDQ7S5A0Xc My CGA Hacking/Snow video: https://www.youtube.com/watch?v=Ll3Zp3kr8l4 CGA card redux: https://github.com/hkzlab/CGA_Redux Great article on how CGA fonts work: https://www.andavno.com/?p=499 Adrian's Digital Basement Merch store: https://my-store-c82bd2-2.creator-spring.com/ Adrian's Digital Basement ][ (Second Channel) https://www.youtube.com/channel/UCbtwi4wK1YXd9AyV_4UcE6g Support the channel on Patreon: https://www.patreon.com/adriansdigitalbasement My GitHub repository: https://github.com/misterblack1?tab=repositories -- Tools Deoxit D5: https://amzn.to/2VvOKy1 http://store.caig.com/s.nl/it.A/id.1602/.f O-Ring Pick Set: (I use these to lift chips off boards) https://amzn.to/3a9x54J Elenco Electronics LP-560 Logic Probe: https://amzn.to/2VrT5lW Hakko FR301 Desoldering Iron: https://amzn.to/2ye6xC0 Rigol DS1054Z Four Channel Oscilloscope: https://www.rigolna.com/products/digital-oscilloscopes/1000z/ Head Worn Magnifying Goggles / Dual Lens Flip-In Head Magnifier: https://amzn.to/3adRbuy TL866II Plus Chip Tester and EPROM programmer: (The MiniPro) https://amzn.to/2wG4tlP https://www.aliexpress.com/item/33000308958.html TS100 Soldering Iron: https://amzn.to/2K36dJ5 https://www.ebay.com/itm/TS100-65W-MINI-Digital-OLED-Programmable-Soldering-Iron-Anti-static-Structure/113382669853 EEVBlog 121GW Multimeter: https://www.eevblog.com/product/121gw/ DSLogic Basic Logic Analyzer: https://amzn.to/2RDSDQw https://www.ebay.com/itm/USB-Logic-DSLogic-Basic-Analyzer-16Ch-100MHz-4Ch-400MHz-Xilinx-Spartan-6-FPGA/202543965672 Magnetic Screw Holder: https://amzn.to/3b8LOhG https://www.harborfreight.com/4-inch-magnetic-parts-tray-90566.html Universal ZIP sockets: (clones, used on my ZIF-64 test machine) https://www.ebay.com/itm/14-16-18-20-24-28-32-40-pin-IC-Test-Universal-ZIF-Socket-Fs/303206721971 RetroTink 2X Upconverter: (to hook up something like a C64 to HDMI) http://www.retrotink.com/ Plato (Clone) Side Cutters: (order five) https://www.ebay.com/itm/1-2-5-10PCS-Micro-Scissor-125mm-PLATO-170-Electronics-Cutter-Side-Cutting-Pliers/163458746184 Heat Sinks: https://www.aliexpress.com/item/32537183709.html Little squeezy bottles: (available elsewhere too) https://amzn.to/3b8LOOI --- Instructional videos My video on damage-free chip removal: https://www.youtube.com/watch?v=XQVjwPsVFd8 --- Music Intro music and other tracks by: Nathan Divino @itsnathandivino