Virginia Cave Is The Largest Musical Instrument In The World

November 9, 2023 by 23 Comments

Hit something with a hammer, and it makes a sound. If you’re lucky, it might even make a pleasant sound, which is the idea behind the Great Stalacpipe Organ in Luray Caverns, Virginia. The organ was created in 1954 by [Leland W. Sprinkle], who noticed that some stalactites (the ones that come down from the ceiling of the cave) would make a nice, pure tone when hit.

So, he did what any self-respecting hacker would do: he picked and carved 37 to form a scale and connected them to an electronic keyboard. The resonating stalactites are spread around a 3.5 acre (14,000 square meters) cave, but because it is in a cave, the sound can be heard anywhere from within the cave system, which covers about 64 acres (260,000 square meters). That makes it the largest musical instrument in the world.

We’ll save the pedants the trouble and point out that the name is technically an error — this is not a pipe organ, which relies on air driven into resonant chambers. Instead, it is a lithophone, a percussion instrument that uses rock as the resonator. You can see one of the solenoids that hits the rock to make the sound below.

This is also the sort of environment that gives engineers nightmares: a constant drip-drip-drip of water filled with minerals that love to get left behind when the water evaporates. Fortunately, the Stalacpipe Organ seems to be in good hands: according to an NPR news story about it, the instrument is maintained by lead engineer for the caverns [Larry Moyer] and his two apprentices, [Stephanie Beahm] and [Ben Caton], who are learning the details of maintaining a complex device like this.

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Forever Writing On Monofilament Fishing Line

November 8, 2023 by 50 Comments

Collectively, we have a long-term memory problem. Paper turns to mulch, dyes in optical disks degrade, iron oxides don’t last forever, and flash memories will eventually fade away. So what do you do when you want to write something down and make sure it’s around a couple of thousand years from now? Easy — just use something that even Mother Nature herself has trouble breaking down: plastic.

Specifically, fluoropolymer fishing line, which is what [Nikolay Valentinovich Repnitskiy] uses as a medium in his “Carbon Record” project. There’s not a lot of information in the repository, but the basic idea is to encode characters by nicking the fishing line along its length. The encoder is simple enough; a spool of fresh line is fed into a machine where a solenoid drives a sharpened bolt against the filament. This leaves a series of nicks that encode the ones and zeros of 255 ASCII characters. It looks like [Nikolay] went through a couple of prototypes before settling on the solenoid; an earlier version used a brushed motor to drive the encoder, but the short, rapid movements proved too much for the motor to handle. We’ve included a video below that shows the device encoding some text; sounds a little like Morse to us.

There seems to be a lot more going on with this device than the repo lets on; we’d love to know what the big heat sink on top is doing, for instance. Hopefully we’ll get more details, including how [Nikolay] intends to decode the dents. Or perhaps that’s an exercise best left to whoever finds these messages a few millennia hence.

2G Or Not 2G, That Is The Question

November 8, 2023 by 66 Comments

Since the very early 1990s, we have become used to ubiquitous digital mobile phone coverage for both voice and data. Such has been their success that they have for many users entirely supplanted the landline phone, and increasingly their voice functionality has become secondary to their provision of an always-on internet connection. With the 5G connections that are now the pinnacle of mobile connectivity we’re on the fourth generation of digital networks, with the earlier so-called “1G” networks using an analogue connection being the first. As consumers have over time migrated to the newer and faster mobile network standards then, the usage of the older versions has reduced to the point at which carriers are starting to turn them off. Those 2G networks from the 1990s and the 2000s-era 3G networks which supplanted them are now expensive to maintain, consuming energy and RF spectrum as they do, while generating precious little customer revenue.

Tech From When Any Phone That Wasn’t A Brick Was Cool

A 1990s Motorola phone
If this is your phone, you may be in trouble. Digitalsignal, CC BY-SA 3.0.

All this sounds like a natural progression of technology which might raise few concerns, in the same way that nobody really noticed the final demise of the old analogue systems. There should be little fuss at the 2G and 3G turn-off. But the success of these networks seems to in this case be their undoing, as despite their shutdown being on the cards now for years, there remain many devices still using them.

There can’t be many consumers still using an early-2000s Motorola Flip as their daily driver, but the proliferation of remotely connected IoT devices means that there are still many millions of 2G and 3G modems using those networks. This presents a major problem for network operators, utilities, and other industrial customers, and raises one or two questions here at Hackaday which we’re wondering whether our readers could shed some light on. Who is still using, or trying to use, 2G and 3G networks, why do they have to be turned off in the first place, and what if any alternatives are there when no 4G or 5G coverage is available? Continue reading “2G Or Not 2G, That Is The Question” →

Hackaday Prize 2023: Ending 10 Years On A High Note

November 7, 2023 by 18 Comments

It’s a fact of life — all good things must eventually come to an end. The trick is not to focus so much on the chapter that’s closing, but look ahead to what comes next. This is precisely how the Hackaday Prize ended its incredible ten-year run on Saturday during Supercon.

This final year of the competition saw some of the most impressive entries we’ve ever had, leaving us with five exceptionally promising winners. These projects exemplify the qualities that the Hackaday Prize was designed to seek out and amplify and make a perfect capstone for this grand experiment in philanthropic hacking.

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Flipped Transformer Powers Budget-Friendly Vacuum Tube Amp

November 7, 2023 by 31 Comments

If you’ve ever wondered why something like a radio or a TV could command a hefty fraction of a family’s yearly income back in the day, a likely culprit is the collection of power transformers needed to run all those hungry, hungry tubes. Now fast-forward a half-century or more, and affordable, good-quality power transformers are still a problem, and often where modern retro projects go to die. Luckily, [Terry] at D-Lab Electronics has a few suggestions on budget-friendly transformers, and even shows off a nice three-tube audio amp using them.

The reason transformers were and still are expensive has a lot to do with materials. To build a transformer with enough oomph to run everything takes a lot of iron and copper, the latter of which is notoriously expensive these days. There’s also the problem of market demand; with most modern electronics favoring switched-mode power supplies, there’s just not a huge market for these big lunkers anymore, making for a supply and demand equation that’s not in the hobbyist’s favor.

Rather than shelling out $70 or more for something like a Hammond 269EX, [Terry]’s suggestion is to modify an isolation transformer, specifically the Triad N-68X. The transformer has a primary designed for either 120 or 230 volts, and a secondary that delivers 115 volts. Turn that around, though, and you can get 230 volts out from the typical North American mains supply — good enough for the plate supply on the little amp shown. That leaves the problem of powering the heaters for the tubes, which is usually the job of a second 6- or 12-volt winding on a power transformer. Luckily, the surplus market has a lot of little 6.3-volt transformers available on the cheap, so that shouldn’t be a problem.

We have to say that the amp [Terry] put these transformers to work in sounds pretty amazing — not a hint of hum. Good work, we say, but we hope he has a plan in case the vacuum tube shortage gets any worse.

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Nixie Tube RPN Calculator Project

November 7, 2023 by 12 Comments

If you like Nixie tubes and/or DIY calculators, checkout this interesting talk from the HP Handheld Conference in Orlando last month by [Eric Smith] from Brouhaha and [John Doran] from Time Fracture. For 20-some years, [Eric] and the late [Richard Ottosen] have been incrementally developing various DIY calculators — this paper from the 2005 HHC conference is an excellent overview of the early project. [John] got one of those early DIY calculators and set about modifying it to use Nixie tubes. However, he got distracted by other things and set it aside — until reviving it earlier this year and enlisting [Eric]’s aid.

This presentation goes over the hardware aspects of the design. Unlike the earlier PIC-based DIY calculators, they decided to use a WCH RISC-V processor this time around. The calculator’s architecture is intentionally modular, with the display and keyboard housed in completely separate enclosures communicating by a serial interface. If the bulkiness alone doesn’t exclude it from being pocket-sized, the 170 VDC power supply and 1/2 W per digit power consumption certainly does. This modularity does lend itself to DIYers replacing the display, or the keyboard, with something different. [Eric] wants to build a mechanical flip-digit display for his unit. As for the software, [Eric] reviews the firmware approach and some future upgrades, such as making it programmable and emulating other flavors of HP calculators.

If you’re embarking on a similar project yourself, check out this talk and take notes — there are a lot of interesting tidbits on using Nixie tubes in the 21st century. If [Eric]’s name sounds familiar, you may know him from the Nonpareil calculator software used on many emulators and DIY calculator projects, one of which we covered some years ago. [John] is also a long-time tinkerer, and we wrote about his gorgeous D16/M HCMOS computer system back in 2012. Thanks to [Stephen Walters] for sending in the tip.

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Oh, The Places You’ll Go With Stop Motion Animation

November 5, 2023 by 5 Comments

Robots made of broken toy parts, stop-motion animation, and a great song to tie it all together were not on our bingo card for 2023, but the results are perfect. [Mootroidxproductions] recently released the official music video for I Fight Dragons 2019 song “Oh the Places You’ll Go”.

The song was written by lead vocalist [Brian Mazzaferri] with inspiration from the classic Dr. Seuss book. [Brian] wrote it for his newborn daughter, and we’re pretty sure it will hit any parent right in the feels.

[Mootroidxproductions] isn’t a parent themselves, but they expanded on the theme to create a video about sacrificing oneself to save a loved one. With a self deprecating wit, they take us through the process of turning broken Bionicle parts, bits of Gundam, Lego, and, armature wire to make the two robots in the film. He also explains how he converted garbage into sets, greebles, and lighting effects.

The robots had to be designed so that they could fulfill their roles in the film. From the size of their hands down to their individual walking gaits, he thought of everything. His encyclopedic knowledge of Bionicle parts is also on full display as he explains the origin of the major parts used to build “Little Blue” and “Sherman”

Click through the break for both the main video and the behind-the-scenes production.

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