TRS-80 Model 4P 80-column crash repair (Part 2) @adriansdigitalbasement
TRS-80 Model 4P 80-column crash repair (Part 2)  @adriansdigitalbasement
Uploaded October 2022 | Updated September 2026, 3 weeks ago
#diagnostics #septandy #trs-80 #model4p

Bonus: CRT brightening mod

We're back with the final repair video on the TRS-80 Model 4P! The machine is now fully operational and I was surprised which part that was actually bad on it. Watch to find out which bad part was the culprit and see how I found it.

Part 1: youtu.be/-EhhU-mCyp0
Part 2: youtu.be/JgqqT4Ewgzs
Part 3: This part!

--- Video Links

Model 1/3/4/4P Diagnostic ROMs:
github.com/misterblack1/trs80-diagnosticrom

ShadowTron Blog running the Model 4 diagnostic disk:
youtu.be/DYJtutZu7tQ?t=208

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
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Adrians Digital Basement |

TRS-80 Model 4P 80-column crash repair (Part 2)

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