Subchannel Stations: The Radio Broadcasts You Didn’t Know Were There

December 20, 2024 by Lewin Day 30 Comments

Analog radio broadcasts are pretty simple, right? Tune into a given frequency on the AM or FM bands, and what you hear is what you get. Or at least, that used to be the way, before smart engineers started figuring out all kinds of sneaky ways for extra signals to hop on to mainstream broadcasts.

Subcarrier radio once felt like the secret backchannel of the airwaves. Long before Wi-Fi, streaming, and digital multiplexing, these hidden signals beamed anything from elevator music and stock tickers to specialized content for medical professionals. Tuning into your favorite FM stations, you’d never notice them—unless you had the right hardware and a bit of know-how.

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Why Did Early CD-ROM Drives Rely On Awkward Plastic Caddies?

December 18, 2024 by Lewin Day 44 Comments

These days, very few of us use optical media on the regular. If we do, it’s generally with a slot-loading console or car stereo, or an old-school tray-loader in a desktop or laptop. This has been the dominant way of using consumer optical media for some time.

Step back to the early CD-ROM era, though, and things were a little kookier. Back in the late 1980s and early 1990s, drives hit the market that required the use of a bulky plastic caddy to load discs. The question is—why did we apparently need caddies then, and why don’t we use them any longer?

Caddyshack

*Early CD players, like this top-loading Sony D-50, didn’t use caddies. Credit: Binarysequence, CC BY-SA 4.0*

The Compact Disc, as developed by Phillips and Sony, was first released in 1982. It quickly became a popular format for music, offering far higher fidelity than existing analog formats like vinyl and cassettes. The CD-ROM followed in 1985, offering hundreds of megabytes of storage in an era when most hard drives barely broke 30 MB. The discs used lasers to read patterns of pits and lands from a reflective aluminum surface, encased in tough polycarbonate plastic. Crucially, the discs featured robust error correction techniques so that small scratches, dust, or blemishes wouldn’t stop a disc from working.

Notably, the first audio CD player—the Sony CDP-101—was a simple tray-loading machine. Phillips’ first effort, the CD100, was a top-loader. Neither used a caddy. Nor did the first CD-ROM drives—the Phillips CM100 was not dissimilar from the CD100, and tray loaders were readily available too, like the Amdek Laserdrive-1. Continue reading “Why Did Early CD-ROM Drives Rely On Awkward Plastic Caddies?” →

Sony Vaio Revived: How Does One Start?

December 16, 2024 by Arya Voronova 22 Comments

A long-term project of mine is the the Sony Vaio new mainboard project. A year ago, I used it as an example to show you the cool new feature in KiCad 8, known as “background bitmaps”.

There are a heap of cool aspects to this specific Sony Vaio. It’s outrageously cute and purse-sized, the keyboard is nice enough for typing, motherboard schematics are available (very important!), and it’s not too terribly expensive. Of course, the most motivating aspect is that I happen to own one, its mainboard is not in the best state, and I’ve been itching to make it work.

It turned out to be a pretty complicated project, and, there was plenty to learn – way more than I expected in the beginning, too. I’m happy to announce that my v1 PCB design has been working wonders so far, and there are only a few small parts of it left untested.

I know that some of you might be looking to rebuild a lovely little computer of your choice. Hell, this particular laptop has had someone else rebuild it into a Pi-powered handheld years ago, as evidenced by this majestic “mess of wires” imgur build log! In honor of every hacker who has gotten their own almost-finished piece of hardware waiting for them half-assembled on the shelf, inside a KiCad file, or just inside your mind for now, let’s go through the tricks and decisions that helped make my board real.

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The Hovercraft Revolution And Finding The Right Niche For A Technology

December 11, 2024 by Maya Posch 41 Comments

In the world of transportation, some technologies may seem to make everything else appear obsolete, whether it concerns airplanes, magnetic levitation or propelling vehicles and craft over a cushion of air. This too seemed to be the case with hovercraft when they exploded onto the scene in the 1950s and 1960s, seemingly providing the ideal solution for both commercial and military applications. Freed from the hindrances of needing a solid surface to travel upon, or a deep enough body of water to rest in, hovercraft gave all the impressions of combining the advantages of aircraft, ships and wheeled vehicles.

Yet even though for decades massive passenger and car-carrying hovercraft roared across busy waterways like the Channel between England & mainland Europe, they would quietly vanish again, along with their main competition in the form of super fast passenger catamarans. Along the English Channel the construction of the Channel Tunnel was a major factor here, along with economical considerations that meant a return to conventional ferries. Yet even though one might think that the age of hovercraft has ended before it ever truly began, the truth may be that hovercraft merely had to find its right niches after a boisterous youth.

An example of this can be found in a recent BBC article, which covers the British Griffon Hoverwork company, which notes more interest in new hovercraft than ever, as well as the continued military interest, and from rescue workers.

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Disc Film,When Kodak Pushed Convenience Too Far

December 10, 2024 by Jenny List 47 Comments

Having a penchant for cheap second-hand cameras can lead to all manner of interesting equipment. You never know what the next second-hand store will provide, and thus everything from good quality rangefinders an SLRs to handheld snapshot cameras can be yours for what is often a very acceptable price. Most old cameras can use modern film in some way, wither directly or through some manner of adapter, but there is one format that has no modern equivalent and for which refilling a cartridge might be difficult. I’m talking about Kodak’s Disc, the super-compact and convenient snapshot cameras which were their Next Big Thing in the early 1980s. In finding out its history and ultimate fate, I’m surprised to find that it introduced some photographic technologies we all still use today.

Easy Photography For The 1980s

Since their inception, Kodak specialised in easy-to-use consumer cameras and films. While almost all the film formats you can think of were created by the company, their quest was always for a super-convenient product which didn’t require any fiddling about to take photographs. By the 1960s this had given us all-in-one cartridge films and cameras such as the Instamatic series, but their enclosed rolls of conventional film made them bulkier than required. The new camera and film system for the 1980s would replace roll film entirely, replacing it with a disc of film that would be rotated between shots to line up the lens on an new unexposed part of its surface. Thus the film cartridge would be compact and thinner than any other, and the cameras could be smaller, thinner, and lighter too. The Disc format was launched in 1982, and the glossy TV adverts extolled both the svelteness of the cameras and the advanced technology they contained. Continue reading “Disc Film,When Kodak Pushed Convenience Too Far” →

Unconventional Oil Production, All You Need To Know

December 5, 2024 by Jenny List 48 Comments

It’s fair to say that climate change is perhaps the greatest challenge facing our planet, and while much attention is directed towards solutions to the problems it presents, perhaps there’s less attention given to the the other side of the equation in the hydrocarbon industry. For example we all think we know something about hydraulic fracking wells, but how much do we really know?

[John Thurmond] is a geologist who has recently completed a long career in the oil industry, and he gave an informative talk on the matter at the summer’s EMF Camp in the UK. It makes for an interesting watch, as he leads the viewer through the process in detail, before discussing what should and shouldn’t cause worry.

We learn that fracking has two parts: first the hydraulic fracking itself, and then the re-injection of the toxic fracking well water released from underground along with the oil or gas. It seems the water released from the rocks a 10,000 ft depth contains all manner of toxic and even radioactive compounds, and the usual means of disposal is to inject it back into the ground at a much lower depth. He makes the point that while the hazards associated with the fracking are low, those of the re-injection are high.

The talk finishes up with perhaps the most interesting point, by looking at the nature of opposition to fracking, or indeed any other controversial development. Such things are inevitably surrounded by a swirling mess of half-truths, and his point is that identifying those easily deflected as not true is key to understanding the whole thing. It’s presented from an expert and factual perspective that’s so often lacking in this arena, and thus we think it’s worth a watch.

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A Brief History Of Teleportation

December 5, 2024 by Al Williams 88 Comments

OK, I know. We don’t have practical teleportation. But that hasn’t stopped generations of science fiction authors and movie makers from building stories around it. If you ask most ordinary people, they’d tell you the idea originated with the Star Trek transporter, but that’s far from the truth. So when did people start thinking about teleporting?

Ground Rules

Maybe it isn’t fair, but I will draw the line at magic or unexplained teleportation. So “The Tempest”, for example, doesn’t use technology but magic. To get to Barsoom, John Carter wished or slept to teleport to Mars. So, while technology might seem like magic, we’re focusing on stories where some kind of machine can send something — usually people — to somewhere else.

Of course, there’s a fine line between pure magic and pure technology where they overlap. For example, in the opera “Der Ring des Nibelungen”, a magic helmet gives people powers, including that of teleportation. While you could argue that Tarnhelm — the name of the magic helmet — was a technological artifact, it is still explained by magic, not science.

Some systems need a transmitter and a receiver. Sometimes, you only need the transmitter. Sometimes, you can only teleport within a limited range, but other make-believe systems can transport an entire starship across the galaxy.

Early Teleporters

The Man without a Body is a story from 1877 in which a scientist is able to transmit a cat via a telegraph wire. Encouraged, he attempts the same feat with himself, but the battery dies in the middle, leaving him with a disembodied head. The ending is decidedly devoid of science, but the story is possibly the earliest one with a machine sending matter across a distance.

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