Looking At A TRS-80 12 MB External Hard Drive From 1983

September 12, 2026 by Maya Posch 19 Comments

Although hard disks weren’t a common feature yet in many home computers in the 1980s, they were becoming increasingly more affordable. For relative meanings of the word ‘affordable’, naturally. This is illustrated by the 12 MB HDD for the Radio Shack TRS-80 that [Clint] over at LGR recently took a peek at.

Costing a cool $3,495 in 1983 – or $11,932 in 2026 USD – this 12 MB storage wonder used a Tandon TM-603 full-height 5.25″ HDD inside. Lacking a working TRS-80 to try it out with, the video is limited to just a basic powering up and opening up of the unit, but [Clint] will be donating it to a computer museum who can hopefully put it to use again.

The connection to the TRS-80 computer is handled by a ribbon cable, while the HDD has its own built-in power supply, rated at 60 Watt.

On the main board for the external HDD controller there is a Signetics 8X300 microprocessor that forms the brains of what makes it into an external drive for the TRS-80. Despite its age, it still looks brand new inside, so despite the Rifa capacitors in the PSU, [Clint] decided to power it on. This resulted in an auditory experience that’s probably best compared to a very rusty jet engine spinning up after languishing for a decade prior to spooling up for take-off.

Hopefully we’ll find out whether this particular unit and its HDD are still working in 2026.

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One Bit Sound With The ZX Spectrum

September 8, 2026 by Al Williams 10 Comments

[Michael] has a thing for playing audio over beepers using a single bit. He’s done it with the Apple ][ and the IBM PC. This time he turns to the ZX Spectrum. He didn’t get quite as good a result — at least not yet — but he did manage to get some things working. He documents everything, so even though this wasn’t a successful week, there’s sometimes more to learn from reasonable failures than from unreasonable successes.

Of course, the whole thing relies on pulse code or pulse width modulation. Of the two techniques, PWM should produce better results. However, he wasn’t able to get PWM working yet. Some other target computers drive the buzzer through a dedicated hardware timer. However, with the Spectrum, it is all software.

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A Vacuum Tube Computer For The Home

September 7, 2026 by Jenny List 10 Comments

The earliest all-electronic computers used vacuum tubes, and most of us will know about machines such as ENIAC or Colossus. Vast machines that required the budget of a country at war to build, andfill very large rooms. It’s very pleasing then to see that a useful vacuum tube computer can be made which has neither of these requirements, as with this example from [Mike] that uses former eastern bloc double-triodes.

It’s an 8-bit design following a von Neumann architecture with 16 instructions, whose operational block diagram would be instantly recognisable to anyone used to working with a 1970s-era 8-bit microcomputer. It follows a NOR-based design in the same manner as the famous NASA machines from the Apollo programme, and as we understand from the description it uses more modern parts for its I/O circuitry. Physically it’s a surprisingly compact wall-mounted unit, and it has an accompanying ex-British Rail flip-digit display as well as a control panel for a simple airship simulator game. There’s a website with full details, if you are interested.

We like this machine, a lot. It may not be the largest computer we’ve seen and it certainly isn’t the first one with vacuum tubes, but it’s a very impressive achievement to have created it. If tubes in computing interest you meanwhile, we took a trip to see the daddy of them all.

Should [Mike] enter this into the Retrocomputing Challenge? We think so.

NES Radar Tracks Flights At 9600 Baud

September 6, 2026 by Tyler August 4 Comments

Air traffic visualizers seem to be having a bit of a moment right now, and now that moment has come to the venerable NES thanks to [k6lcm]’s NES Radar project, which is open-source under the GPL on GitHub. In spite of the name, there’s no Radio Direction or Range-Finding involved in this project– no radio at all, in fact, which makes this a bit interesting. It’s just an NES cartridge and a carefully constructed cable.

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WordStar Lives Again (and Again)

September 6, 2026 by Al Williams 30 Comments

Word processors and editors are a funny thing. It doesn’t really matter what’s “best,” whatever that means. If you have finger memory built up for one program, it’s painful to change. That’s why most of us don’t learn how to type on a Dvorak keyboard and why [George R. R. Martin] writes with WordStar. Many people of a certain age have a deep memory of WordStar. Now you can run it on a modern machine or even in your browser without a lot of trouble, thanks to [nampara-ai].

The idea is simple. Take a vintage copy of WordStar for MSDOS, wrap it with DOSBox, and package it up with some basic scripts for Linux, Mac, or Windows. In addition, there’s a WebAssembly version for the browser if you’re into that sort of thing.

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Running Apple ][ Software On A Commodore 64 — Silently

September 5, 2026 by Al Williams 8 Comments

The computer business in 1984 was a bizarre mix of hobby-level companies, a few small companies that had made it big, and a lot of big companies starting to take notice of personal computers. Plenty of money followed, which led to strange products and even stranger ads. [Such Bad Tech Ads] reveals a very bad ad from that time for a product we have barely heard of: the Spartan. The Spartan’s job was to convert your Commodore 64 so it could run Apple ][ software. The ad campaign had, inexplicably, a mime. We think. Or maybe a clown. Hard to say.

On the face of it, the Spartan might not be a bad idea. In 1984, there was plenty of Apple software. Well, relatively, anyway. But a Commodore computer was far cheaper. Other conversion kits like the Intel Inboard/386 managed to find some success in the market later. The problem, outside of strange ads, was one of timing.

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COSMAC Elf Turns 50

September 4, 2026 by Al Williams 28 Comments

If you were interested in computers in the early 1970s, you struggled to get time on real computers since owning your own was all but impossible. In the middle of the decade, though, you could get a few computers: the Mark VIII, the Altair, the Apple I, and several others. Those were still pretty expensive, though. But in late 1976, an article in Popular Electronics said you could build a “powerful, expandable” computer for $80. The article in question was by [Joseph Weisbecker], who, unknown to most of us at the time, was actually the RCA employee behind the CPU — an RCA 1802. [Tech Time Traveler] takes a close look at the spunky little computer’s history in the video you can see below.

The 1802 was actually the second generation of the CPU, but the first that was all-in-one chip. [Weisbecker] started building the CPU as a personal project. He’d been a hacker even in high school, building relay-based tic-tac-toe games, among other things.

The first incarnation in his lab was “Fred,” with 100 TTL chips, and his idea was to have the computer be at least partially used as a video game — an interesting point, with Pong being very popular at the time.

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