The False Alarm That Nearly Sparked Nuclear War

April 16, 2021 by Lewin Day 54 Comments

The date was September 26, 1983. A lieutenant colonel in the Soviet Air Defence Forces sat at his command station in Serpukhov-15 as sirens blared, indicating nuclear missiles had been launched from the United States. As you may have surmised by the fact you’re reading this in 2021, no missiles were fired by either side in the Cold War that day. Credit for this goes to Stanislav Petrov, who made the judgement call that the reports were a false alarm, preventing an all-out nuclear war between the two world powers. Today, we’ll look at what caused the false alarm, and why Petrov was able to correctly surmise that what he was seeing was an illusion.

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History Of Closed Captions: The Analog Era

April 14, 2021 by Chris Lott 46 Comments

Closed captioning on television and subtitles on DVD, Blu-ray, and streaming media are taken for granted today. But it wasn’t always so. In fact, it was quite a struggle for captioning to become commonplace. Back in the early 2000s, I unexpectedly found myself involved in a variety of closed captioning projects, both designing hardware and consulting with engineering teams at various consumer electronics manufacturers. I may have been the last engineer working with analog captioning as everyone else moved on to digital.

But before digging in, there is a lot of confusing and imprecise language floating around on this topic. Let’s establish some definitions. I often use the word captioning which encompasses both closed captions and subtitles:

Closed Captions: Transmitted in a non-visible manner as textual data. Usually they can be enabled or disabled by the user. In the NTSC system, it’s often referred to as Line 21, since it was transmitted on video line number 21 in the Vertical Blanking Interval (VBI).

Subtitles: Rendered in a graphical format and overlaid onto the video / film. Usually they cannot be turned off. Also called open or hard captions.

The text contained in captions generally falls into one of three categories. Pure dialogue (nothing more) is often the style of captioning you see in subtitles on a DVD or Blu-ray. Ordinary captioning includes the dialogue, but with the addition of occasional cues for music or a non-visible event (a doorbell ringing, for example). Finally, “Subtitles for the Deaf or Hard-of-hearing” (SDH) is a more verbose style that adds even more descriptive information about the program, including the speaker’s name, off-camera events, etc.

Roughly speaking, closed captions are targeting the deaf and hard of hearing audience. Subtitles are targeting an audience who can hear the program but want to view the dialogue for some reason, like understanding a foreign movie or learning a new language.

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Weren’t We Supposed To Live In Plastic Houses In The Future?

April 13, 2021 by Jenny List 117 Comments

Futurism is dead. At least, the wildly optimistic technology-based futurism of the middle years of the 20th century has been replaced in our version of their future by a much more pessimistic model of environmental challenges and economic woes. No longer will our flying cars take us from our space-age wonder-homes to the monorail which will whisk us through sparkling-clean cities to our robotised workplaces, instead while we may have a global computer network and voice controlled assistants we still live in much the same outdated style as we did decades ago. Our houses are made from wood and bricks by blokes with shovels rather than prefabricated by robots and delivered in minutes, and our furniture would be as familiar to a person from the 1950s as it is for us.

A Plastic Future That Never Quite Happened

There was a time when the future of housing looked remarkably different. Just as today we are busily experimenting with new materials and techniques in the type of stories we feature on Hackaday, in the 1950s there was a fascinating new material for engineers and architects to work with in the form of plastics. The Second World War had spawned a huge industry that needed to be repurposed for peacetime production, so almost everything was considered for the plastic treatment, including houses. It seemed a natural progression that our 21st century houses would be space-age pods rather than the pitched-roof houses inherited from the previous century, so what better way could there be to make them than using the new wonder material? A variety of plastic house designs emerged during that period which remain icons to this day, but here we are five or six decades later and we still don’t live in them. To find out why, it’s worth a look at some of them, partly as a fascinating glimpse of what might have been, but mostly to examine them with the benefit of hindsight.

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Hershey Fonts: Not Chocolate, The Origin Of Vector Lettering

March 30, 2021 by Chris Lott 57 Comments

Over the past few years, I kept bumping into something called Hershey fonts. After digging around, I found a 1967 government report by a fellow named Dr. Allen Vincent Hershey. Back in the 1960s, he worked as a physicist for the Naval Weapons Laboratory in Dahlgren, Virginia, studying the interaction between ship hulls and water. His research was aided by the Naval Ordnance Research Calculator (NORC), which was built by IBM and was one of the fastest computers in the world when it was first installed in 1954.

The NORC’s I/O facilities, such as punched cards, magnetic tape, and line printers, were typical of the era. But the NORC also had an ultra-high-speed optical printer. This device had originally been developed by the telecommunications firm Stromberg-Carlson for the Social Security Administration in order to quickly print massive amounts of data directly upon microfilm.

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Unicode: On Building The One Character Set To Rule Them All

March 17, 2021 by Maya Posch 75 Comments

Most readers will have at least some passing familiarity with the terms ‘Unicode’ and ‘UTF-8’, but what is really behind them? At their core they refer to character encoding schemes, also known as character sets. This is a concept which dates back to far beyond the era of electronic computers, to the dawn of the optical telegraph and its predecessors. As far back as the 18th century there was a need to transmit information rapidly across large distances, which was accomplished using so-called telegraph codes. These encoded information using optical, electrical and other means.

During the hundreds of years since the invention of the first telegraph code, there was no real effort to establish international standardization of such encoding schemes, with even the first decades of the era of teleprinters and home computers bringing little change there. Even as EBCDIC (IBM’s 8-bit character encoding demonstrated in the punch card above) and finally ASCII made some headway, the need to encode a growing collection of different characters without having to spend ridiculous amounts of storage on this was held back by elegant solutions.

Development of Unicode began during the late 1980s, when the increasing exchange of digital information across the world made the need for a singular encoding system more urgent than before. These days Unicode allows us to not only use a single encoding scheme for everything from basic English text to Traditional Chinese, Vietnamese, and even Mayan, but also small pictographs called ‘emoji‘, from Japanese ‘e’ (絵) and ‘moji’ (文字), literally ‘picture word’.

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Historical Hackers: Hero Builds Vending Machines

March 12, 2021 by Al Williams 14 Comments

We tend to think of mechanical contrivances as products of the industrial revolution and true automation as something computers handle. Yet even before computers, automation existed — using timing motors and cams and other mechanical contraptions. But it might surprise you to know that there was actually some sophisticated automation going way back. Really way back, invented in a world without computers, CAD software, or even electricity. For example, around 50 AD an inventor named Hero — sometimes known as Heron — built machines powered by steam and wind. His inventions included vending machines and music players.

It is hard to imagine what kind of music player or, indeed, vending machine you could build in 50AD. Some of Hero’s inventions were used in temples to, for example, dispense holy water. Others were used in theater to do things like automatically lighting a fire or creating thunder effects. There was even an entirely automated puppet show that used knotted ropes to put on a ten-minute production with no human assistance.

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A Brief History Of Viruses

February 22, 2021 by Will Sweatman 23 Comments

It was around the year 1590 when mankind figured out how to use optical lenses to bring into sight things smaller than the natural eye can observe. With the invention of the microscope, a new and unexplored world was discovered. It will likely be of great surprise to the reader that scientists of the time did not believe that within this new microscopic realm lay the source of sickness and disease. Most would still hold on to a belief of what was known as Miasma theory, which dates back to the Roman Empire. This theory states that the source of disease was contaminated air through decomposing organic materials. It wouldn’t be until the 1850’s that a man by the name of Louis Pasteur, from whom we get “pasteurization”, would promote Germ Theory into the spotlight of the sciences.

Louis Pasteur experimenting in his lab. — Louis Pasteur. Source

Pasteur, considered by many as the father of microbiology, would go on to assist fellow biologist Charles Chameberland in the invention of the aptly named Pasteur Chamberland filter — a porcelain filter with a pore size between 100 and 1000 nanometers. This was small enough to filter out the microscopic bacteria and cells known at that time from a liquid suspension, leaving behind a supply of uncontaminated water. But like so many other early scientific instrumentation inventions it would lead to the discovery of something unexpected. In this case, a world far smaller than 100 nanometers… and add yet another dimension to the ever-shrinking world of the microscopic.

This is when we began to learn about viruses.

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