Back before LED technology came into its own, displays used incandescent bulbs. These vintage incandescent displays weren’t necessarily big; the Eaton 925H-C fiber optic display, for example, has numbers barely 7 mm tall and packs two of them into a tiny area. Of course, the depth of the display module itself is huge by today’s standards; those components have got to go somewhere, after all.
This particular device is, in [Industrial Alchemy]’s words, “[d]ripping with the spending excess that only a bottomless military budget can provide… the Eaton 925H-C may not be a practical device, but it is certainly an impressive one.”
The way the display works is this: individual incandescent bulbs light up fiber optic light guides, which terminate on the face of the display in small dots to make up a numerical display. With only fourteen bulbs, the dots we see here clearly aren’t individually addressable; the two digits are most likely broken up into seven segments each, with three dots making up each segment.
The sheer amount of workmanship in these displays is remarkable, and their design makes them easy to retrofit with LED technology instead of replacing the tiny incandescent lamps. In a stark contrast to all of the machined aluminum and gold plated contacts seen here in the Eaton 925H-C, take a look at this Soviet-era seven-segment incandescent display whose construction is far less sophisticated, but shows off its own clever engineering. We’ve also seen more modern DIY takes on the concept, using LED light sources and cured UV resin light pipes to get that vintage look to the displays.
There’s plenty of specialised, high-end scientific equipment out there running on antique hardware and software. It’s not uncommon for old lab equipment to run on DOS or other ancient operating systems. When these expensive tools get put out to pasture, they often end up in the hands of hackers, who, without the benefit of manuals or support, may try and get them going again. [Jerry Biehler] is trying to do just that with a 740AD spectrometer, built by Optronic Laboratories in the 1990s.
Originally, the device shipped with a whole computer – a Leading Edge 386SX25 PC running DOS and Windows 3.0. The tools to run the spectrometer were coded in BASIC. Armed with the source code, [Jerry] was able to recreate the functionality in LabVIEW. To replace the original ISA interface board, an Advantech USB-4751 digital IO module was used instead, which dovetailed nicely with its inbuilt LabVIEW support.
With things back up and running, [Jerry] has put the hardware through its paces, testing the performance of some IR camera filters. Apparently, the hardware, or the same model, was once used to test the quantum efficiency of CCDs used on the Hubble Space Telescope.
After Young built the prototype, three of these were made and put into cases cut out of scrap plexiglass) from a dumpster — hence they became known as Crystal Palaces after the 1851 glass and iron structure of the same name.
[Sam] decides to build this using some inductors and an old tape head. After proving out the concept on a breadboard, he mounts sixteen inductors on a 3D-printed circular frame. The rotating pickup transfers the signal via slip-rings at the top. An array of input jacks and level pots are mounted on the enclosure’s face plate, which contains a vector board full of op amps that drive the coils. Strictly speaking, the original fader used capacitive coupling, not inductive, but that doesn’t detract at all from this project. And as he states upfront, he intentionally didn’t dig too deep into the original, so as to put his own spin on the design.
Resin printers can offer excellent surface finish and higher detail than other 3D printing technologies, but they come with their own set of drawbacks. One is that they’re quite sensitive to temperature, generally requiring the resin chamber to be heated to 25-30 degrees Celsius for good performance. To help maintain a stable temperature without a lot of mucking around, [Grant] put together a simple chamber heater for his printer at home.
Rather than go for a custom build from scratch with a microcontroller, [Grant] was well aware that off-the-shelf solutions could easily do the job. Thus, a W1209 temperature control board was selected, available for under $5 online. Hooked up to a thermocouple, it can switch heating elements via its onboard relay to maintain the set temperature desired. In this case, [Grant] chose a set of positive-temperature coefficient heating elements to do the job, installing them around the resin chamber for efficiency.
The heater can preheat the chamber in under fifteen minutes, much quicker than other solutions using space heaters or heat mats. The time savings will be much appreciated by [Grant], we’re sure, along with the attendant increase in print quality. If you’re still not sure if resin printing is for you, have a read of our primer. And, if you’ve got your own workflow improvements for resin printing, drop us a line!
Pen input has never really taken off in the computing mainstream, though it’s had somewhat of a renaissance in the last decade or so. Various smartphones and tablets are shipping with the technology, and some diehard users swear by it as the best way to take notes on the go. Recently, researchers at the Sensing, Interaction and Perception Lab at ETH Zurich have been working on Flashpen, a high-fidelity pen interface for a wide range of applications.
The fundamental technology behind the pen is simple, with the device using an optical flow sensor harvested from a high-end gaming mouse. This is a device that uses an image sensor to detect the motion of the sensor itself across a surface. Working at an update rate of 8 KHz, it eclipses other devices in the market from manufacturers such as Wacom that typically operate at rates closer to 200Hz. The optical sensor is mounted to a plastic joint that allows the user to hold the pen at a natural angle while keeping the sensor parallel to the writing surface. There’s also a reflective sensor on the pen tip which allows cameras to track its position in space, for use in combination with VR technology.
Here at Hackaday, we’re always working as hard as we can to bring you the latest and most exciting technologies, and like so many people we’ve become convinced that the possibilities offered by the rise of the Blockchain present unrivaled opportunities for humanity to reinvent itself unfettered by the stifling regulations of a dying system. This is why today we’ve decided to join in with the digital cognoscenti and celebrities embracing Non-Fungible Tokens, or NFTs, as a new promise of non-corporeal digital investment cryptoasset that’s taking the world by storm.
Crypto Non-Fungible Investment Gains!
An NFT is a digital token representing something in the real world, and coupled to a unique ID held in a secure entry in the Blockchain. It’s non-fungible, which means that it’s unique and not interchangeable in the manner of a traditional old-style cryptoasset such as Bitcoin. As it allows a real-world object to be tokenised in digital form it represents a way to own something that provides an irrefutable connection to it as as a digital cryptoasset.
It’s a complex system that’s maybe too difficult to explain fully in a single article, but think of an NFT as a way to invest in a cryptoasset in digital form with its uniqueness guaranteed by Blockchain security, without having the inconvenience of physically owning it. Instead your NFT is safely held on a server on the Internet, and can’t be physically stolen as it would from a bank vault because it has the Blockchain cryptosecurity baked in.
Non Fungible Blockchain Cryptoassets!
NFTs have so far found a space in the creative markets, where they have provided a revolutionary opportunity for artists to expand their sales in the digital realm by selling NFTs of their work. A struggling artist can now access buyers all over the world, who can in turn now invest with confidence in creative talent to which they would never otherwise be exposed. It’s a win-win situation in which both cryptoinvestor and artist benefit from The Power of the Blockchain.
Hackaday is excited to offer a once-in-a-lifetime chance to acquire a Blockchain-cryptosecured NFT representing one of our own articles; our first ever NFT is the only officially sanctioned digital copy of a Hackaday article presenting a novel method of handling toilet paper shortages. The original article will continue to exist on Hackaday.com with all rights reserved, but we will not make any other NFTs of it. We may also decide to update the original article to let everyone know you are the lucky owner of the only digital copy of this piece of greatness. That’s right, this NFT will let you prove you own a screenshot!
Having today sold you on the incredible cryptoinvestment opportunity offered by NFTs, we’ll be back on another date with a more sober and in-depth technical examination of the technology behind them. Meanwhile should our brief foray into NFTs garner any interest (and we really hope it does not), we will donate proceeds to the excellent Girls Who Code, a truly solid investment with a tangible bright future.
Thanks [Micah Scott] for some NFT consultancy during the making of this piece.
And the emphasis is on empty extinguisher. Part of the deal involves twisting the gauge off, and we wouldn’t want you to get blasted in the face with any last gasps of high-powered firefighting foam. In order to make the thing re-pressurizable, [liquidhandwash] stripped all the rubber from a tire valve and removed the core temporarily so it could be soldered into the fitting where the gauge was. The handy hose is from a large can of WD-40, which is also where the label came from — since it’s no longer a fire extinguisher, it needs to stop bearing resemblance to one, so [liquidhandwash] removed the sticker, painted it blue, and glued the cut-open can to the outside.
To use it, [liquidhandwash] fills it up about halfway and then pressurizes it through the tire valve with a bike pump or compressor. (We think we’d go with bike pump.) Since [liquidhandwash] goes through so much lubricant, now, they can just buy it by the gallon and keep refilling the extinguisher.