Adrians Digital Basement | Using our new diagnostic ROM to fix a TRS-80 Model III! @adriansdigitalbasement | Uploaded August 2022 | Updated October 2024, 1 hour ago.
#trs-80 #repair

The TRS-80 Model III is fixed! As you saw in part 1, I was really stumped by the problems this board had -- so I reached out to friends Frank and David about making a diagnostic ROM for this machine. I posted a companion video on the second channel taking a deeper dive to the ROM, I recommend you watch that after watching this video. The repair showed off how even someone as "seasoned" as me can make fundamental mistakes in the troubleshooting process.... So watch to find out what mistakes I made, and what it took to get this machine running again!

Thanks for Frank IZ8DWF and David KI3V for making the diagnostic ROM a reality.

Part 1: youtu.be/EGFKjjlvKf4
Part 2: This part!

Diagnostic ROM deep dive companion video:
youtu.be/4fuuyLiSgsE

--- Video Links

TRS-80 Model 3 (and Model 1) diagnostic ROM:
github.com/misterblack1/trs80-diagnosticrom

2364 adapter PCB:
pcbway.com/project/shareproject/Adapter_2364___27128__by_Bobbel_.html

Frank IZ8DWF's channel: (for really amazing repairs)
youtube.com/c/iz8dwf

When good caps go bad: (t-shirt donated by Jesse)
teepublic.com/t-shirt/24171882-when-caps-go-bad

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

-- 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

--- Links

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

Commodore Computer Club / Vancouver, WA – Portland, OR – PDX Commodore Users Group
commodorecomputerclub.com

--- Instructional videos

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

--- Music

Intro music and other tracks by:
Nathan Divino
@itsnathandivino