The Sinclair ZX Spectrum Turns 40

April 26, 2022 by Jenny List 68 Comments

It’s an auspicious moment for retrocomputing fans, as it’s now four decades since the launch of the Sinclair ZX Spectrum. This budget British microcomputer was never the best of the bunch, but its runaway success and consequent huge software library made it the home computer to own in the UK. Here in 2022 it may live on only in 1980s nostalgia, but its legacy extends far beyond that as it provided an entire generation of tech-inclined youngsters with an affordable tool that would get them started on a lifetime of computing.

What Was 1982 Really Like?

Cover of Sincalir User, Sir Clive Sinclair as a magician — Sinclair User issue 3 captures the excitement surrounding the Spectrum launch.

There’s a popular meme among retro enthusiasts that the 1980s was a riot of colour, pixel artwork, synth music, and kitschy design. The reality was of growing up amid the shabby remnants of the 1970s with occasional glimpses of an exciting ’80s future. This was especially true for a tech-inclined early teen, as at the start of 1982 the home computer market had not yet reached its full mass-market potential. There were plenty of machines on offer but the exciting ones were the sole preserve of adults or kids with rich parents. Budget machines such as Sinclair’s ZX81 could give a taste of what was possible, but their technical limitations would soon become obvious to the experimenter.

1982 was going to change all that, with great excitement surrounding three machines. Here in the UK, the Acorn BBC Micro had been launched in December ’81, the Commodore 64 at the start of ’82, and here was Sinclair coming along with their answer in the form of first the rumour of a ZX82, and then the reality in the form of the Spectrum.

This new breed of machines all had a respectable quantity of memory, high-res (for the time!) colour graphics, and most importantly, sound. The BBC Micro was destined to be the school computer of choice and the 64 was the one everybody wanted, but the Spectrum was the machine you could reasonably expect to get if you managed to persuade your parents how educational it was going to be, because it was the cheapest at £125 (£470 in today’s money, or about $615). Continue reading “The Sinclair ZX Spectrum Turns 40” →

IBM PCjr Types Again, Thanks To KeybJr

April 24, 2022 by Donald Papp 6 Comments

Most of us think of keyboards — even vintage ones — as being fairly standardized and interchangeable, but that isn’t the case for the IBM PCjr. Its keyboard was quite unlike most others of its time, which means that a PCjr without an original keyboard is pretty much a dust collector. That’s what led [Jozef Bogin] to create the KeybJr, a piece of hardware that allows one to use any AT, XT, or PS/2 keyboard with the IBM PCjr.

The PCjr’s oddball keyboard can be a bit of a hassle for vintage computing enthusiasts.

What was strange about the PCjr’s keyboard? From the outside it looked pretty normal, but it definitely had its own thing going on. For one, the PCjr keyboard operated over a completely different protocol than the other keyboards of the time. In addition, its connection to the host was either by IR, or via its own wired cable adapter.

The KeybJr solves this by using an Arduino-based board to turn inputs from other keyboards of the time into something the PCjr expects. These signals are sent out and received either over infrared, or by the PCjr’s “K” port for a wired keyboard link.

Why bother with the IR functionality? Well, the connector and pins on the PCjr are not very rugged, and sometimes they are damaged. In those cases, it is nice to have the option of using a normal (for the time) keyboard over the IR link. Vintage hardware is not always in perfect shape, after all. That’s why things like ATX power supply adapters for the PCjr exist.

Want to give it a shot? There is a GitHub repository for the KeybJr, and you can see it in action in a brief video, embedded below.

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Commodore C64: The Most Popular Home Computer Ever Turns 40

April 20, 2022 by Bil Herd 107 Comments

This year marks the anniversary of the most popular selling home computer ever, the Commodore 64, which made its debut in 1982. Note that I am saying “home computer” and not personal computer (PC) because back then the term PC was not yet in use for home computer users.

Some of you have probably not heard of Commodore, which is kind of sad, though there is a simple reason why — Commodore is no longer around to maintain its legacy. If one were to watch a documentary about the 1980s they may see a picture of an Apple computer or its founders but most likely would not see a picture of a Commodore computer in spite of selling tens of millions of units.

To understand the success of the C64 I would first back up and talk about the fabled era of home computers which starts with understanding the microprocessor of the day, the venerable 6502. Check out the video and follow along below.

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The Epic Journey Of Repairing An HP 9830A Desktop Computer From The 1970s

April 18, 2022 by Robin Kearey 10 Comments

We love our retrocomputers here at Hackaday, and we’re always delighted to see someone rescue an historic artefact from the landfill. Sometimes, all it takes is replacing a broken power switch or leaky capacitor; other times you need to bring out the oscilloscope and dig deeper into internal circuitry. But the huge amount of work [Jerry Walker] put into bringing an HP 9830A back on its feet is something you don’t see very often.

If you’re not familiar with the HP 9830A, it’s a desktop computer from the early 1970s, fully built from discrete logic gates. The machine on [Jerry]’s desk turned out to be completely dead, with not even the fan spinning up. This was caused by a dodgy power switch, but replacing that switch was just the beginning: there were several bad components inside the power supply as well as a huge amount of moist dirt on the back of the motherboard. After a thorough cleaning and the replacement of several failed components, all four power rails were running within spec again.

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Javascript Is Everywhere. Even MSDOS

April 15, 2022 by Al Williams 35 Comments

Although pundits have joked that Java’s “write once, run everywhere” slogan might be better expressed as “write once, debug everywhere,” a relative of Java — JavaScript — has delivered on both promises better than its namesake. Thanks to its proliferation in browsers, JavaScript is a veritable lingua franca of computer languages which has led to entire applications being written in it using tools like Node.js and Electron, and not just browsers. But what if you are still using MSDOS or Windows 98? We know some of you do, at least on retro machines. Don’t feel left out, the DOjS project has jSH, a JavaScript engine for DOS and related operating systems.

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We’ve Heard Of Bricking A Hard Drive, But…

April 14, 2022 by Al Williams 38 Comments

Mass storage has come a long way since the introduction of the personal computer. [Tech Time Traveller] has an interesting video about the dawn of PC hard drives focusing on a company called MiniScribe. After a promising start, they lost an IBM contract and fell on hard times.

Apparently, the company was faking inventory to the tune of $15 million because executives feared for their jobs if profits weren’t forthcoming. Once they discovered the incorrect inventory, they not only set out to alter the company’s records to match it, but they also broke into an outside auditing firm’s records to change things there, too.

Senior management hatched a plan to charge off the fake inventory in small amounts to escape the notice of investors and government regulators. But to do that, they need to be able to explain where the balance of the nonexistent inventory was. So they leased a warehouse to hold the fraud inventory and filled it with bricks. Real bricks like you use to build a house. Around 26,000 bricks were packaged in boxes, assigned serial numbers, and placed on pallets. Auditors would see the product ready to ship and there were even plans to pretend to ship them to CompuAdd and CalAbco, two customers, who had agreed to accept and return the bricks on paper allowing them to absorb the $15 million write off a little at a time.

Unfortunately, the fictitious excellent financial performance led to an expectation of even better performance in the future which necessitated even further fraud. The company had turned around, but only on paper. A downturn in the computer business and maxed-out credit signaled the beginning of the end. Suppliers and employees weren’t getting paid. A senior manager violated insider trader rules and dumped a lot of stock.

The turnaround CEO finally resigned and a new CEO found the fraud and released the findings that they were in the hole for $100 million. Bankruptcy pushed the company’s assets to Maxtor and criminal charges against 16 people ensued ending in fines and jail time. It isn’t clear if any of the boxed bricks were shipped to anyone by accident or by a disgruntled employee with a rubber paycheck. [Tech Time Traveller] speculates that if someone has one, it would be quite the collector’s item.

We hear about companies doing questionable things, of course, but this really is impressive in scope. At least they weren’t scamming end users as some tech companies have done.

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A Close Look At A Little Known 8-bit Computer

April 8, 2022 by Al Williams 47 Comments

If you read about the history of personal computing, you hear a few familiar names like Microsoft, Apple, and even Commodore. But there were a host of companies that were well known and well regarded back then that are all but forgotten today. Godbout computing, Ohio Scientific, and Southwest Technical Products (SWTP). SWTP is probably best remembered for having a relatively cheap printer and “TV typewriter”, but they also made a 6800-based computer and [Adrian] takes us inside of one.

The 6800 was Motorola’s entry into the microprocessor fray, competing with the Intel 8080. The computer came out scant months after the introduction of the famous Altair 8800. Although the Altair is often credited as being the first hobbyist-grade computer, there were a few earlier ones based on the 8008, but the Altair was the first to be successful.

The SWTP was notable for its day for its blank appearance. Most computers in those days had lots of switches and lights. The SWTP has a blank front with only a power switch and a reset button. A ROM monitor let you use the machine with a terminal. For about the same price as a bare-bones Altair that had no interfaces or memory, you could pick one of these up with most of the extras you would need. The memory was only 2K, but that was 2K more than you got with an Altair at that price point.

The $450 sounds fairly cheap, but in the early 70s, that was a lot of lawns to mow. Of course, while you’d need to add memory to the Altair, you’d have to add some kind of terminal to the SWTP. However, you’d wind up with something more usable but the total bill was probably going to approach $1,000 to get a working system.

Inside the box were some old-fashioned-looking PC boards and connectors that will look familiar to anyone who has been inside 1970s gear. Will it work? We don’t know yet, but we hope it does. [Adrian] promises that will be in the next video.

It is amazing how far we’ve come in less than 50 years. A postage-stamp sized $10 computer now has enough speed and memory to emulate a bunch of these old machines all at once. The SWTP has been on our pages before. A lot of these old machines and companies are all but forgotten, but not by us!

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