The Lancaster ASCII Keyboard Recreated

November 25, 2024 by Al Williams 20 Comments

It is hard to imagine that there was a time when having a keyboard and screen readily available was a real problem for people who wanted to experiment with computers. In the 1970s, if you wanted a terminal, you might well have built a [Don Lancaster] “TV Typewriter” and the companion “low cost keyboard.” [Artem Kalinchuk] wanted to recreate this historic keyboard and, you know what? He did! Take a look at the video below.

The first task was to create a PCB from the old artwork from Radio Electronics magazine. [Artem] did the hard work but discovered that the original board expected a very specific kind of key. So, he created a variant that takes modern MX keyboard switches, which is nice. He does sell the PCBs, but you can also find the design files on GitHub.

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TV Typewriter Remembered

July 20, 2023 by Al Williams 22 Comments

With the recent passing of Don Lancaster, I took a minute to reflect on how far things have come in a pretty short period of time. If you somehow acquired a computer in the early 1970s, it was probably some discarded DEC, HP, or Data General machine. A few people built their own, but that was a stout project with no microprocessor chips readily available. When machines like the Mark-8 and, more famously, the Altair appeared, the number of people with a “home computer” swelled — relatively speaking — and it left a major problem: What kind of input/output device could you use?

An ad from Kilobaud offered you a ready-to-go, surely refurbished, ASR33 for $840

At work, you might have TeleType. Most of those were leased, and the price tag of a new one was somewhere around $1,000. Remember, too, that $1,000 in 1975 was a small fortune. Really lucky people had video terminals, but those were often well over $1,500, although Lear Siegler introduced one at the $1,000 price, and it became wildly successful. Snagging a used terminal was not very likely, and surplus TeleType equipment was likely of the 5-bit Baudot variety — not unusable, but not the terminal you really wanted.

A lot of the cost of a video terminal was the screen. Yet nearly everyone had a TV, and used TVs have always been fairly cheap, too. That’s where Don Lancaster came in. His TV Typewriter Cookbook was the bible for homebrew video displays. The design influenced the Apple 1 computer and spawned a successful kit for a company known as Southwest Technical Products. For around $300 or so, you could have a terminal that uses your TV for output. Continue reading “TV Typewriter Remembered” →

Computer Thing Might Be Garbage

May 15, 2022 by Al Williams 9 Comments

[Tech Time Traveller] has a lot of voices in his head this week, and most of them are worried about his wife’s reaction to him buying other people’s garbage. We don’t blame him, though. He bought it from an estate sale and it was billed as a TV typewriter. The device looked completely homebrewed from somewhere around the late 1970s to the early 1980s. It contains a mess of components obviously hand-built in a combination of neat construction and messy wiring.

[Tech] videos most of his tests and exploration to get the thing working and tested. Given its age and construction, it worked surprisingly well, although it did take a little work to get it back to complete function. In fact, he bought the device three years ago and is finally getting around to finishing the project and putting together the video.

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The Computer Of Yesterday, Today

June 27, 2017 by Brian Benchoff 16 Comments

There are a handful of computers that have become true museum pieces. The Altair, of course, is tucked away in the Smithsonian’s warehouse waiting for some time in the future when Apple’s legacy fades or until there’s a remake of War Games. Likewise, the French Micral and American SCELBI are important historical artifacts, and even a modern component-accurate reproduction of an Apple I could fetch a decent amount of cash at the right auction.

There’s something special about these old kit computers – even though the instructions for these machines provided volumes of documentation, no one is building these machines anymore. You just can’t buy the PCBs, and sourcing period-correct components is hard. [Brad] is an exception. He found original, untouched PCBs for the cover story of the July, 1974 edition of Radio-Electronics. It’s an unbuilt Mark-8 minicomputer. Now [Brad] is in a position no one else has been in since the 1970s: he can build a vintage minicomputer, with a TV Typewriter, from scratch. He’s documenting the whole thing.

Since this is the first opportunity this century anyone has had to build a truly retro minicomputer, [Brad] is going all-in with this project. For an interface, he’s building [Don Lancaster]’s TV Typewriter, a device introduced in the September 1973 issue Radio-Electronics. When combined with an old CRT TV, the TV Typewriter becomes a serial terminal. While today something like this could be built around a single microcontroller, constructing the TV Typewriter is no small feat: it’s spread across four boards, uses character generator ROMs, and is currently housed in a beautiful red oak case.

Just because [Brad] is building an ancient computer using ancient parts doesn’t mean he can’t get a little help from modern technology. He’s applying white silk screen to his custom TV Typewriter boards using the toner transfer process. Yes, apparently you can get toner cartridges filled with white (and neon!) toner, and this works well enough to replicate the look of professionally silk screened boards.

This is one of the greatest retrocomputing projects we’ve seen in a very long time. This is a true retrocomputer, complete with custom transformers and gigantic linear power supplies. When this project is complete, [Brad] will have a museum piece, all thanks to a lucky find of an eBay auction and a lot of hard work.