The Hunt For Alien Radio Signals Began Sooner Than You Think

March 20, 2024 by Lewin Day 22 Comments

Every 26 months, Earth and Mars come tantalizingly close by virtue of their relative orbits. The closest they’ve been in recent memory was a mere 55.7 million kilometers, a proximity not seen in 60,000 years when it happened in 2003.

However, we’ve been playing close attention to Mars for longer than that. All the way back in 1924, astronomers and scientists were contemplating another close fly by from the red planet. With radio then being the hot new technology on the block, the question was raised—should we be listening for transmissions from fellows over on Mars?

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Retrotechtacular: Air Mail For The Birds

March 14, 2024 by Al Williams 9 Comments

Today, if you want to send a message to a distant location, you’ll probably send an e-mail or a text message. But it hasn’t always been that easy. Military commanders, in particular, have always needed ways to send messages and were early adopters of radio and, prior to that, schemes like semaphores, drums, horns, Aldis lamps, and even barrels of water to communicate over distances.

One of the most reliable ways to pass messages, even during the last world war, was by carrier pigeon. Since the U.S. Army Signal Corps handled anything that included messages, it makes sense that the War Department issued TM 11-410 about how to use and care for pigeons. Think of it as the network operations guide of 1945. The practice, though, is much older. There is evidence that the Persians used pigeons in the 6th century BC, and Julius Caesar’s army also used the system.

You wouldn’t imagine that drawing an assignment in the Signal Corps might involve learning about breeding pigeons, training them, and providing them with medical attention, but that’s what some Signal Corps personnel did. The Army started experimenting with pigeons in 1878, but the Navy was the main user of the birds until World War I, when the U.S. Pigeon Intelligence Service was formed. In World War II, they saw use in situations where radio silence was important, like the D-Day invasion.

The Navy also disbanded its earlier Pigeon Messenger Service. It then returned to avian communications during the World Wars, using them to allow aviators to send messages back to base without radio traffic. The Navy had its own version of the pigeon manual.

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Retro Gadgets: Pay TV In The 1960s

March 8, 2024 by Al Williams 20 Comments

These days, paying for TV programming is a fact of life. You pay your cable company or some streaming service and the only question is do you want Apple TV and Hulu or would you rather switch one out for NetFlix? But back in the 1960s, paying for TV seemed unthinkable and was quite controversial. Cable TV systems were rare, and the airwaves were a public resource, so allowing someone to charge to watch TV on the public airwaves was hard to imagine. That was the backdrop behind the Telemeter — an early attempt to monetize TV programming that was more like a pay phone than a modern streaming service.

[Lothar Stern] wrote about the device in the November 1959 issue of Popular Mechanics (see page 220). The device looked like a radio that sat on top of your TV. It added a whopping three pay-TV channels, and inside was a coin box, and — no kidding — a tape punch or recorder. These three channels were carried from a Telemeter studio over what appears to be a dedicated cable strung on existing phone poles.

Of course, TVs with coin boxes were nothing new. But those TVs were found in public places, airports, and hotels. The money was simply to turn the TV on for a set amount of time. This was different. A set-top box unscrambled channels delivered over a dedicated cable. Seems like old hat today, but a revolutionary idea in 1959.

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PC AT mainboard with both 16-bit ISA and 32-bit PCI slots. (Credit: htomari, Flickr)

How Intel Gave Us The PCI Bus While Burying VESA’s VL-Bus

February 15, 2024 by Maya Posch 39 Comments

Gigabyte GA486IM mainboard from 1994 with ISA, VLB and PCI slots. (Credit: Rjluna2, Wikimedia)

The early days of home computing were quite a jungle of different standards and convoluted solutions to make one piece of hardware work on as many different platforms as possible. IBM’s PC was an unexpected shift here, as with its expansion card-based system (retroactively called the ISA bus) it inspired a new evolution in computers. Of course, by the early 1990s the ISA bus couldn’t keep up with hardware demands, and a successor was needed. Many expected this to be VESA’s VLB, but as [Ernie Smith] regales us in a recent article in Tedium, Intel came out of left field with its PCI standard after initially backing VLB.

IBM, of course, wanted to see its own proprietary MCA standard used, while VLB was an open standard. One big issue with VLB is that it isn’t a new bus as such, but rather an additional slot tacked onto the existing ISA bus, as it was then called. While the reasoning for PCI was sound, with it being a compact, 32-bit (also 64-bit) design with plug and play and more complex but also more powerful PCI controller, its announcement came right before VLB was supposed to be announced.

Although there was some worry that having both VLB and PCI in the market competing would be bad, ultimately few mainboards ended up supporting VLB, and VLB quietly vanished. Later on PCI was extended into the Accelerated Graphics Port (AGP) that enabled the GPU revolution of the late 90s and still coexists with its PCIe successor. We covered making your own ISA and PCI cards a while ago, which shows that although PCI is more complex than ISA, it’s still well within the reach of today’s hobbyist, unlike PCIe which ramps up the hardware requirements.

Top image: PC AT mainboard with both 16-bit ISA and 32-bit PCI slots. (Credit: htomari, Flickr)

Sprint: The Mach 10 Magic Missile That Wasn’t Magic Enough

February 13, 2024 by Lewin Day 74 Comments

Defending an area against incoming missiles is a difficult task. Missiles are incredibly fast and present a small target. Assuming you know they’re coming, you have to be able to track them accurately if you’re to have any hope of stopping them. Then, you need some kind of wonderous missile of your own that’s fast enough and maneuverable enough to take them out.

It’s a task that at times can seem overwhelmingly impossible. And yet, the devastating consequences of a potential nuclear attack are so great that the US military had a red hot go anyway. In the 1970s, America’s best attempt to thwart incoming Soviet ICBMs led to the development of the Sprint ABM—a missile made up entirely of improbable numbers.

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Vesuvius Challenge 2023 Grand Prize Awarded And 2024’s New Challenge

February 7, 2024 by Maya Posch 7 Comments

In the year 79 CE, a massive cloud of volcanic ash rained down on the Roman city of Herculaneum after an eruption of Mount Vesuvius. Along with the city of Pompeii, Herculaneum was subsequently engulfed and buried by a pyroclastic flow that burned everything in its path, including the scrolls in the library of what today is known as the Villa of the Papyri. After the charred but still recognizable scrolls were found in the 18th century, many fruitless attempts were made to recover the text hidden within these charred ruins, but not until 2023 did we get our first full glimpse at their contents, along with the awarding of the Vesuvius Challenge 2023.

We previously covered the run-up to this award, but with only a small fraction of the scrolls now read, there’s still a long way to go. This leads to the 2024 prize challenge, which sees teams strive to read 90% of scrolls 1-4 each, for a $100,000 award. The expectation is that with this ability, it should be possible to read all 800 scrolls known today, but as detailed in the Master Plan there is still more to come. Being able to scan and process scrolls faster and more efficiently is one of the biggest challenges, as is that of recovering any more scrolls that may be stuck in the mud at the Villa of the Papyri. As easy as it may sound to pull stuff out of the mud, archaeological excavations are expensive and time-consuming.

With time running out on how long both the recovered and still lost scrolls will last, it’s pertinent that we do not lose this opportunity to double our knowledge of historical texts from this era.

The World’s First Microprocessor: F-14 Central Air Data Computer

January 30, 2024 by Maya Posch 34 Comments

When the Grumman F-14 Tomcat first flew in 1970, it was a marvel. With its variable-sweep wing, twin tail, and sleek lines, it quickly became one of the most iconic jet fighters of the era — and that was before a little movie called Top Gun hit theaters.

A recent video by [Alexander the ok] details something that was far less well-documented about the plane, namely its avionics. The Tomcat was the first aircraft to use a microprocessor-driven flight system, as well as the first microprocessor unit (MPU) ever demonstrated, beating the Intel 4004 by a year. In 1971, one of the designers of the F-14’s Central Air Data Computer (CADC) – [Ray Holt] – wrote an article for Computer Design magazine that was naturally immediately classified by the Navy until released to the public in 1998.

The MPU in the CADC is called the Garrett AiResearch MP944, and consists of a number of ICs that together form a full computer. These were combined in the CADC with additional electronics to control many elements of the airplane automatically, including the weapons system and the variable-sweep wing configuration. This was considered to be essential based on experiences with the F-111 and its very complex electromechanical flight computer, which was an evolution of the 1950s-era Bendix CADC.

The video goes through the differences between the 4-bit Intel 4004 and the 20-bit MP944, questioning whether the 4004 is even really an MPU, the capabilities of the MP944 and its system architecture. Ultimately the question of ‘first’ and that of ‘what is an MPU’ will always be somewhat fuzzy depending on your definitions, but there is no denying that the MP944 was a marvel of large-scale integration.

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