Hackaday Links Column Banner

Hackaday Links: February 11, 2024

Apple’s Vision Pro augmented reality goggles made a big splash in the news this week, and try as we might to resist the urge to dunk on them, early adopters spotted in the wild are making it way too easy. Granted, we’re not sure how many of these people are actually early adopters as opposed to paid influencers, but there was still quite a bit of silliness to be had, most of it on X/Twitter. We’d love to say that peak idiocy was achieved by those who showed themselves behind the wheels of their Teslas while wearing their goggles, with one aiming for an early adopter perfecta, but alas, most of these stories appear to be at least partially contrived. Some people were spotted doing their best to get themselves killed, others were content to just look foolish, especially since we’ve heard that the virtual keyboard is currently too slow for anything but hunt-and-peck typing, which Casey Niestat seemed to confirm with his field testing. After seeing all this, we’re still unsure why someone would strap $4,000 worth of peripheral-vision-restricting and easily fenced hardware to their heads, but hey — different strokes. And for those of you wondering why these things are so expensive, we’ve got you covered.

Continue reading “Hackaday Links: February 11, 2024”

Hackaday Links Column Banner

Hackaday Links: October 3, 2021

It’s one thing to speculate about what’s happening with the Mars helicopter Ingenuity, but it’s another to get an insider’s view on recent flight problems. As we previously reported, Ingenuity is starting to face a significant challenge, as a seasonal atmospheric pressure drop on Mars threatens to make the already rarefied air too thin to generate useful lift. Mission controllers tested the chopper at higher rotor speeds, and while that worked, later attempts to fly using that higher speed resulted in an abort. The article, written by one of the NASA/JPL engineers, is a deep dive into the problem, which occurred when Ingenuity sensed excessive wiggle in two of the servos controlling the rotor swashplate. The thought is that accumulated wear in the servos and linkages might be causing the problem; after all, Ingenuity has made thirteen flights so far, greatly exceeding the five flights originally programmed for it. Here’s hoping they can adapt and keep the helicopter flying, but whatever they do, it’ll have to wait a few weeks until Mars completes its conjunction and pops back out from behind the Sun.

With all the attention understandably paid to the recent 20th anniversary of the 9/11 terror attacks, it’s easy to forget that barely a month after that day, a series of what appeared to be follow-on attacks started: the Anthrax Attacks. Members of Congress and media outlets were targeted via the mail with highly refined anthrax spores, leading to the deaths of five people, with dozens more injured and exposed to anthrax. IEEE Spectrum has an interesting article that goes into some of the technology that was rapidly deployed in an attempt to sanitize the mail, including electron beam and X-ray irradiation to kill any spores. The article also points out how this wasn’t the first time people were afraid of the mail; outbreaks of yellow fever in 1899 led to fumigation of the mail with sulfur, after perforating it with a wicked-looking paddle.

Attention PCB-design newbies — now’s your chance to learn the entire PCB design process from the ground up, with the guidance of industry professionals. TeachMePCB is back again this year, offering to teach you everything you need to know about properly laying out a PCB design in pretty much any EDA software you want. The course requires a two- to five-hour commitment every week for two months, after which you’ll have designed a PCB for a macropad using a Raspberry Pi Pico. The course facilitator is Mark Hughes from Royal Circuits, who did a great Hack Chat with us last year on PCB finishes. This seems like a great way to get up to speed on PCB design, so if you’re interested, act soon — 460 people are already signed up, and the deadline is October 10.

Some of us really love factory tours, no matter what the factory is making. All the better when the factory makes cool electronics stuff, and better still when it’s our friends at Adafruit showing us around their New York City digs. True, it’s a virtual tour, but it has pretty much become a virtual world over the last couple of years, and it’s still a great look inside the Adafruit factory. Hackaday got an in-person tour back in 2015, but we didn’t know their building used to be a Westinghouse radio factory. In fact, the whole area was once part of the famed “Radio Row” that every major city seemed to have from the 1920s to the 1960s. It’s good to get a look inside a real manufacturing operation, especially one that’s right in the heart of a city.

And finally, those with a fear of heights might want to avoid watching this fascinating film on the change-out of a TV transmitter antenna. The tower is over 1,500′ (450 m) tall, lofting an aging antenna over the flat Florida terrain. Most of the footage comes from body-mounted cameras on the riggers working the job, including the one very brave soul who climbed up the partially unbolted antenna to connect it to the Sikorsky S64 Skycrane helicopter. It’s a strange combination of a carefully planned and slowly executed ballet, punctuated by moments of frenetic activity and sheer terror. The mishap when releasing the load line after the new antenna was placed could easily have swept the whole rigging crew off the antenna, but luckily nobody was injured.

Continue reading “Hackaday Links: October 3, 2021”

A Dangerous Demonstration Of The Power Of Radio

Terrestrial radio may be a dying medium, but there are still plenty of listeners out there. What would a commute to or from work be without a check of “Traffic on the Eights” to see if you need to alter your route, or an update of the scores from yesterday’s games? Getting that signal out to as many listeners as possible takes a lot of power, and this dangerous yet fascinating demo shows just how much power there is on some radio towers.

Coming to us by way of a reddit post, the short video clips show a crew working on a 15,000-Watt AM radio tower. They appear to be preparing to do tower maintenance, which means de-energizing the antenna. As the engineer explains, antennas for AM radio stations in the medium-wave band are generally the entire tower structure, as opposed to the towers for FM and TV stations, which generally just loft the antenna as high as possible above the landscape. The fun starts when the crew disconnects a jumper and an arc forms across the clamp and the antenna feed. The resulting ball of plasma acts like a speaker, letting us clearly hear the programming on the station. It’s like one of the plasma speakers we’ve seen before, albeit exceptionally more dangerous.

It’s an impressive display of the power coursing through broadcast towers, and a vivid reminder to not mess with them. Such warnings often go unheeded, sadly, with the young and foolish paying the price. There’s a reason they put fences up around radio towers, after all.

Continue reading “A Dangerous Demonstration Of The Power Of Radio”

Texas Tesla Tower Titillates

One of the nice things about a road trip is you often get to see something that really surprises you. A recent trip through Texas may have resulted in my second most surprising sighting. There’s a strange tower that looks oddly like a Tesla tower in the middle of rural Texas, right off the main interstate. What is it? Although Google did answer the question — sort of — I’m still not sure how legitimate its stated purpose is.

First Sighting

I was driving between Wimberly and Frisco — two towns that aren’t exactly household names outside of Texas. Near Milford, there’s a very tall structure that looks like a giant mechanical mushroom on top of a grain silo. If the mushroom were inverted or pointing towards the horizon, it would be easy to imagine it was some very odd antenna. This dish, however, is pointed right down its own odd-shaped mast. The top of the thing sure looks like the top of a Van de Graf generator.

Continue reading “Texas Tesla Tower Titillates”

The Final Days Of The Fire Lookouts

For more than a century, the United States Forest Service has employed men and women to monitor vast swaths of wilderness from isolated lookout towers. Armed with little more than a pair of binoculars and a map, these lookouts served as an early warning system for combating wildfires. Eventually the towers would be equipped with radios, and later still a cellular or satellite connection to the Internet, but beyond that the job of fire lookout has changed little since the 1900s.

Like the lighthouse keepers of old, there’s a certain romance surrounding the fire lookouts. Sitting alone in their tower, the majority of their time is spent looking at a horizon they’ve memorized over years or even decades, carefully watching for the slightest whiff of smoke. The isolation has been a prison for some, and a paradise for others. Author Jack Kerouac spent the summer of 1956 in a lookout tower on Desolation Peak in Washington state, an experience which he wrote about in several works including Desolation Angels.

But slowly, in a change completely imperceptible to the public, the era of the fire lookouts has been drawing to a close. As technology improves, the idea of perching a human on top of a tall tower for months on end seems increasingly archaic. Many are staunchly opposed to the idea of automation replacing human workers, but in the case of the fire lookouts, it’s difficult to argue against it. Computer vision offers an unwavering eye that can detect even the smallest column of smoke amongst acres of woodland, while drones equipped with GPS can pinpoint its location and make on-site assessments without risk to human life.

At one point, the United States Forest Service operated more than 5,000 permanent fire lookout towers, but today that number has dwindled into the hundreds. As this niche job fades even farther into obscurity, let’s take a look at the fire lookout’s most famous tool, and the modern technology poised to replace it.

Continue reading “The Final Days Of The Fire Lookouts”

Emergency Cell Tower On A Budget

Cell phone towers are something we miss when we’re out of range, but imagine how we’d miss them if they had been destroyed by disastrous weather. In such emergencies it is more important than ever to call loved ones, and tell them we’re safe. [Matthew May] and [Brendan Harlow] aimed to make their own secure and open-source cellular network antenna for those occasions. It currently supports calling between connected phones, text messaging, and if the base station has a hard-wired internet connection, users can get online.

This was a senior project for a security class, and it seems that the bulk of their work was in following the best practices set by the Center for Internet Security. They adopted a model intended for the Debian 8 operating system which wasn’t a perfect fit. According to Motherboard their work scored an A+, and we agree with the professors on this one.

Last year, the same SDR board, the bladeRF, was featured in a GSM tower hack with a more sinister edge, and of course Hackaday is rife with SDR projects.

Thank you [Alfredo Garza] for the tip.

Life-Size Vu Meter Gets The Party Started

There’s nothing better than making a giant version of one of your hacks. That is, other than making it giant and interactive. That’s just what [Est] has done with his interactive VU meter that lights up the party.

The giant VU meter boasts a series of IR detectors that change the colors and modes of the meter based on where the user places their hands. The sensors measure how much light is reflected back to them, which essentially function as a cheap range finder. The normal operation of the meter and the new interactivity is controlled by a PIC16F883 and all of the parts were built using a home-made CNC router. There are two addressable RGB LEDs for each level and in the base there are four 3 W RGB LEDS. At 25 levels, this is an impressive amount of light.

[Est]’s smaller version of the VU meter has been featured here before, if you’re looking to enhance your music-listening or party-going experiences with something a little less intimidating. We’ve also seen VU meters built directly into the speakers and also into prom dresses.