Commodore PET 2001 Repair

(This was originally a Twitter thread from November 6, 2017.)

November 6, 2017

A huge box has just arrived! And inside are lots and lots of packing peanuts. Wait, wait, there’s something else in here. It looks like it’s from the future.

Say 10 PRINT”HELLO WORLD” to the Commodore PET 2001 from 1977, one of the “trinity” personal computers. Big thanks to @FozzTexx!

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Radio Shack TRS-80 PC-2 Pocket Computer and Plotter Refurbishment

(This was originally a Twitter thread from November 15, 2019.)

November 15, 2019

Say 10 PRINT “Hello, World!” to my new Radio Shack TRS-80 PC-2 pocket computer with printer cassette docking interface. Has BASIC and “2640-character program and data memory”— so a little over 2.5K of RAM. Many thanks to @FloppyDays, it’s all in tip-top shape!

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Typewriter Plotters

Did you know there were typewriters that used ball point pens to draw not just text but also graphics? I’ve collected several of these over the years. Read on to discover a world that you didn’t know existed.

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Another Commodore 64 Black Screen Repair

(This was originally a Twitter thread on September 23, 2018)

September 23, 2018

On the bench today is a Commodore 64 picked up from @Recta_Pete at Atari Party East 2018. This revision is the cost reduced long board because of the sparse components around the VIC-II. I already spot several problems.

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Commodore 64 Black Screen Repair

(This was originally a Twitter thread from September 26, 2018)

September 26, 2018

Next on the bench is an early #c64, 1982 original motherboard with 5 pin video out and a lovely ceramic VIC-II. These tend to be tricky in my experience.

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Recapping an Epson HX-20 Slabtop

(This was originally a Twitter thread from March 24, 2020)

March 24, 2020

The Epson HX-20 is on the bench for some TLC like a new battery, new capacitors, cassette tape belt, and possibly more. Maybe I’ll eventually dial a BBS with it.

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Recapping the Apple PowerBook 160 LCD Display

(This was originally a Twitter thread from May 26, 2022)

May 26, 2022

Today I’m going to recap the LCD display on this PowerBook 160. It has a passive matrix LCD display capable of displaying 4-bit grayscale (16 shades of gray). The display was dim before with some severe artifacts (after adjusting the contrast slider) but now it will only show a black screen.

@mac84tv has an excellent page that lists the capacitors needed for this recap along with the links to Mouser to purchase.

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Getting Programs For The C64 CP/M Cartridge

Picture of Commodore 64 CP/M Cart and Boot Disc


The Commodore 64 CP/M cartridge was released sometime in the early 1980’s, shortly after the introduction of the C64 itself. The cartridge contained the necessary Z80 chip inside to run CP/M software natively. While a novel idea, it was a bit too late with the popularity of CP/M waning which itself had been released almost a decade earlier. To make matters worse, it seems to only work on very early revisions of the Commodore 64. I personally am only able to get it to work reliably on a Rev A motherboard (1982, with no s-video output).

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