Retro Computing Archives

Apple IIc power supply pinout

Dave Farquhar Retro Computing June 22, 2021March 24, 2023

I recently needed a new power supply for an Apple IIc to replace a missing one. It’s easy to adapt a modern laptop power brick to work with an Apple IIc. All you need is a pinout. Here’s an Apple IIc power supply pinout.

Dave Farquhar

David Farquhar is a computer security professional, entrepreneur, and author. He has written professionally about computers since 1991, so he was writing about retro computers when they were still new. He has been working in IT professionally since 1994 and has specialized in vulnerability management since 2013. He holds Security+ and CISSP certifications. Today he blogs five times a week, mostly about retro computers and retro gaming covering the time period from 1975 to 2000.

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MOS 74LS logic chips

Dave Farquhar Retro Computing May 12, 2021September 25, 2024

Commodore (in)famously owned its own chip manufacturer, MOS Technology, later known as Commodore Semiconductor Group. MOS was pivotal to helping Commodore keep prices low in the early 1980s, as it lowered Commodore’s overhead, and ensured a steady supply of chips. In 1983 and 1984, MOS produced 74LS logic chips. These chips are very failure prone. Here’s how to find MOS 74LS logic chips, and more importantly, what to replace them with.

Dave Farquhar

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Game box repair

Dave Farquhar Retro Computing, Toy trains May 10, 2021March 26, 2024

Vintage computer games and vintage toys display better in their original boxes. But frequently those boxes are in less than ideal condition, especially if you got it at a good price. A pristine box can be worth more than the contents. I recently lucked into a couple of vintage Commodore game cartridge boxes. Their best days were behind them, but I was able to make them presentable again. Here’s my approach to game box repair.

I fixed up quite a few battered books in my day to make them more suitable for resale. The tricks I learned fixing books helped me with fixing game boxes and toy boxes as well.

Dave Farquhar

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Is collecting retro games worth it?

Dave Farquhar Retro Computing May 4, 2021March 26, 2024

I saw an interesting perspective this week on the hobby of collecting retro games, from another retro enthusiast. Prices on retro games, he observes, are increasing. That’s making him ask a tough question: Is collecting retro games worth it?

Any hobby seems like a waste of time to the right (or wrong) person. If a hobby, such as collecting retro games, helps you to unwind and get focused, and you can get some of your money back out of it as you lose interest or approach end of life, then I have to argue that hobby is worth it.

Dave Farquhar

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Compaq Presario 425 and 433

Dave Farquhar Retro Computing April 29, 2021March 3, 2025

The Compaq Presario 425 and 433 are popular machines with retro enthusiasts. They are Compaq 486s from 1993, and they look like exactly what they are. They’re well built, have recognizable branding, and don’t take up a lot of space. In some ways they’re the ideal 486 today. Let’s look at why they weren’t necessarily the ideal 486 for 1993, but they, along with the rest of the Presario line, helped transform Compaq anyway.

Dave Farquhar

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What size nut driver for computers?

Dave Farquhar Hardware, Retro Computing April 28, 2021June 13, 2022

Many modern computers don’t require any tools to work on. But that’s not always the case, especially with vintage computers, or less-expensive DIY cases. A nut driver, also known as a hex driver or hex nut driver, makes things easier. So what is the right size nut driver for computers? Or do you need more than one?

Dave Farquhar

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Cyrix processor chips: In memoriam

Dave Farquhar Retro Computing April 28, 2021April 15, 2026

Cyrix was a scrappy, up and coming CPU manufacturer in the 1990s. They never had Intel’s name recognition, but for a few years they made life more difficult for its larger rivals, Intel and AMD. For a while, Cyrix processor chips were a popular choice for value-conscious PC buyers.

Cyrix contributed a lot of confusing alphabet soup to the 1990s CPU market, and their chips usually weren’t the highest-performing chips available. But they usually did provide good value for the money, even though Cyrix never was a premium brand.

Dave Farquhar

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Commodore 1571 disk drive

Dave Farquhar Retro Computing April 7, 2021January 6, 2026

The Commodore 1571 was Commodore’s successor to the notorious 1541 disk drive. It addressed many of the shortcomings of the 1541, partly because Commodore had more time to get it right this time. It was the same color and style as the Commodore 128. And they worked as well together as they looked together. It was a high-end drive, but I hesitate to call it Commodore’s top-end 5.25-inch drive. I’d give that distinction to the SFD-1001.

Commodore introduced the 1571 in 1985 at a price of $299 US. It was a double-sided, double density 5.25-inch disk drive that was faster than the 1541 when you used it with the 128, and maintained good backward compatibility with the 1541 when needed.

Dave Farquhar

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Retrobright with sunlight and no chemicals

Dave Farquhar Retro Computing April 5, 2021October 4, 2021

I heard earlier this year that you can retrobright without chemicals, using only sunlight. I haven’t heard of a lot of people trying it. But I had a yellowed disk drive, and it’s summertime, so I decided to give it a shot.

A few people experimented with retrobright without chemicals in 2019, then the idea kind of faded away. I decided to try it, and found it works surprisingly well.

Dave Farquhar

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Amstrad PCs: The PC1512 and PC1640

Dave Farquhar Retro Computing February 25, 2021July 27, 2022

The Amstrad PC1512 and PC1640 were inexpensive Korean-made PCs that took Europe by storm in the mid 1980s. Amstrad was the UK’s largest computer maker, and it hoped to replicate that success in the United States as well. Here’s an overview of those machines, and why that effort was less than an overwhelming success.

Dave Farquhar

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