Leading Edge Model D Repair @adriansdigitalbasement
Leading Edge Model D Repair  @adriansdigitalbasement
Uploaded July 2024 | Updated September 2026, 2 weeks ago
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:
youtube.com/watch?v=mqDQ7S5A0Xc

My CGA Hacking/Snow video:
youtube.com/watch?v=Ll3Zp3kr8l4

CGA card redux:
github.com/hkzlab/CGA_Redux

Great article on how CGA fonts work:
andavno.com/?p=499

Adrian's Digital Basement Merch store:
my-store-c82bd2-2.creator-spring.com

Adrian's Digital Basement ][ (Second Channel)
youtube.com/channel/UCbtwi4wK1YXd9AyV_4UcE6g

Support the channel on Patreon:
patreon.com/adriansdigitalbasement

My GitHub repository:
github.com/misterblack1?tab=repositories

-- Tools

Deoxit D5:
amzn.to/2VvOKy1
store.caig.com/s.nl/it.A/id.1602/.f

O-Ring Pick Set: (I use these to lift chips off boards)
amzn.to/3a9x54J

Elenco Electronics LP-560 Logic Probe:
amzn.to/2VrT5lW

Hakko FR301 Desoldering Iron:
amzn.to/2ye6xC0

Rigol DS1054Z Four Channel Oscilloscope:
rigolna.com/products/digital-oscilloscopes/1000z

Head Worn Magnifying Goggles / Dual Lens Flip-In Head Magnifier:
amzn.to/3adRbuy

TL866II Plus Chip Tester and EPROM programmer: (The MiniPro)
amzn.to/2wG4tlP
aliexpress.com/item/33000308958.html

TS100 Soldering Iron:
amzn.to/2K36dJ5
ebay.com/itm/TS100-65W-MINI-Digital-OLED-Programmable-Soldering-Iron-Anti-static-Structure/113382669853

EEVBlog 121GW Multimeter:
eevblog.com/product/121gw

DSLogic Basic Logic Analyzer:
amzn.to/2RDSDQw
ebay.com/itm/USB-Logic-DSLogic-Basic-Analyzer-16Ch-100MHz-4Ch-400MHz-Xilinx-Spartan-6-FPGA/202543965672

Magnetic Screw Holder:
amzn.to/3b8LOhG
harborfreight.com/4-inch-magnetic-parts-tray-90566.html

Universal ZIP sockets: (clones, used on my ZIF-64 test machine)
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)
retrotink.com

Plato (Clone) Side Cutters: (order five)
ebay.com/itm/1-2-5-10PCS-Micro-Scissor-125mm-PLATO-170-Electronics-Cutter-Side-Cutting-Pliers/163458746184

Heat Sinks:
aliexpress.com/item/32537183709.html

Little squeezy bottles: (available elsewhere too)
amzn.to/3b8LOOI

--- Instructional videos

My video on damage-free chip removal:
youtube.com/watch?v=XQVjwPsVFd8

--- Music

Intro music and other tracks by:
Nathan Divino
@itsnathandivino
Leading Edge Model D RepairIs an IBM PC usable at the same clock speed as an Apple II?Is the Casablanca a disguised Amiga? Its complicated.Lets test a 50 year old MOS 6502 CPUThe TRS-80 Model 4 cant do this! The Frankenstein CoCo is alive againPC Archeology: Not just another normal IBM PC XT clone (Handwell PC-401)How to image and create disks for retro computersLunchbox PCs were awesome! Why did they go away? (Dolch PAC-62)Plexus P/20: This is the end.Apple Archeology: Four barn found Apple IIc computersOverclocking this Mac to the limit using scrap parts and period correct modsCRT Archeology: Mystery Toshiba display (GBC MV-10A)
Adrians Digital Basement |

Leading Edge Model D Repair

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