Getting Into NMR Without The Superconducting Magnet

May 26, 2023 by 14 Comments

Exploring the mysteries of quantum mechanics surely seems like an endeavor that requires room-sized equipment and racks of electronics, along with large buckets of grant money, to accomplish. And while that’s generally true, there’s quite a lot that can be accomplished on a considerably more modest budget, as this as-simple-as-it-gets nuclear magnetic resonance spectroscope amply demonstrates.

First things first: Does the “magnetic resonance” part of “NMR” bear any relationship to magnetic resonance imaging? Indeed it does, as the technique of lining up nuclei in a magnetic field, perturbing them with an electromagnetic field, and receiving the resultant RF signals as the nuclei snap back to their original spin state lies at the heart of both. And while MRI scanners and the large NMR spectrometers used in analytical chemistry labs both use extremely powerful magnetic fields, [Andy Nicol] shows us that even the Earth’s magnetic field can be used for NMR.

[Andy]’s NMR setup couldn’t be simpler. It consists of a coil of enameled copper wire wound on a 40 mm PVC tube and a simple control box with nothing more than a switch and a couple of capacitors. The only fancy bit is a USB audio interface, which is used to amplify and digitize the 2-kHz-ish signal generated by hydrogen atoms when they precess in Earth’s extremely weak magnetic field. A tripod stripped of all ferrous metal parts is also handy, as this setup needs to be outdoors where interfering magnetic fields can be minimized. In use, the coil is charged with a LiPo battery for about 10 seconds before being rapidly switched to the input of the USB amp. The resulting resonance signal is visualized using the waterfall display on SDR#.

[Andy] includes a lot of helpful tips in his excellent write-up, like tuning the coil with capacitors, minimizing noise, and estimating the exact resonance frequency expected based on the strength of the local magnetic field. It’s a great project and a good explanation of how NMR works. And it’s nowhere near as loud as an MRI scanner.

When The Professionals Trash Your Data Tape, Can It Still Be Recovered?

May 26, 2023 by 17 Comments

People trying to preserve digital artifacts held on old media often not only have to contend with the media themselves decaying, but also with obscure media formats for which there’s seemingly little chance of finding a working reader. [Kneesnap] had this problem with a tape containing the only known copy of all the assets for the game Frogger 2: Swampy’s Revenge, and the tale of how the data was recovered is a dive into both the shady side of the data recovery industry and some clever old-format hacking.

The tape was an Onstream cartridge, a short-lived format from a company whose first product hit the market at the end of the ’90s and who went bust in 2004. An old drive was found, but it proved to have a pinch roller melted with age, so in desperation the tape was sent to a data recovery company.

We admire the forbearance in not naming and shaming the data recovery company, because far from recovering the data they sent it back with the tape damaged and spliced — something you can do with an analogue tape but not a digital one without compromising the data. Then faced with an unrecoverable tape and a slightly different Onstream cartridge, how could anything be salvaged?

The answer came in overriding the drive’s sensors and initializing it with a known-good tape, then swapping out the tapes so that the drive, unaware anything had changed, could read whatever data it could find. In the event the vast majority of the archive was retrieved, making it a win for the preservation of that game.

This may be more involved than some recovery stories, but it’s not the first we’ve covered.

A Mobile Phone From 1985

May 25, 2023 by 8 Comments

It might seem quaint through the lends of history we have the luxury of looking through, but in the mid 1980s it was a major symbol of status to be able to communicate on-the-go. Car phones and pagers were cutting-edge devices of the time, and even though there were some mobile cellular telephones, they were behemoths compared to anything we would recognize as a cell phone today. It wasn’t until 1985 that a cell phone was able to fit in a pocket, and that first device wasn’t just revolutionary because of its size. It made a number of technological advancements that were extremely impressive for its time, and [Janus Cycle] takes us through some of those in this teardown video.

The Technophone came to us from Great Britain by way of a former Ericsson engineer named Nils Mårtensson. It was able to achieve its relatively small stature using a surface-mount PCB, which was a cutting-edge manufacturing process for the time. Not only did it use surface-mount components and boards, but the PCB itself has 12 layers and two sides and hosts two custom Technophone chips. The phone is relatively modular as well, with the screen, battery pack, and other components capable of easily disconnecting from the main board. Continue reading “A Mobile Phone From 1985” →

Vehicle-to-Grid Made Easy

May 25, 2023 by 37 Comments

As electric cars continue to see increased adoption, one associated technology that was touted long ago that still hasn’t seen widespread adoption is vehicle-to-grid or vehicle-to-home. Since most cars are parked most of the time, this would allow the cars to perform load-levelling for the grid or even act as emergency generators on an individual basis when needed. While this hasn’t panned out for a variety of reasons, it is still possible to use an EV battery for use off-grid or as part of a grid tie solar system, and now you can do it without needing to disassemble the battery packs at all.

Normally when attempting to use a scrapped EV battery for another use, the cells would be removed from the OEM pack and reorganized to a specific voltage. This build, however, eliminates the need to modify the packs at all. A LilyGO ESP32 is used to convert the CAN bus messages from the battery pack to the Modbus communications protocol used by the inverters, in this case a Fronius Gen24, so the inverter and battery can coordinate energy delivery from one to the other automatically. With the hard part out of the way, the only other requirements are to connect a high voltage DC cable from the battery pack to the inverter.

[Dala], the creator of this project, has taken other steps to ensure safety as well that we’d recommend anyone attempting to recreate this build pays close attention to, as these battery packs contain an extremely large amount of energy. The system itself supports battery packs from Nissan Leafs as well as the Tesla Model 3, which can usually be found for comparably low prices. Building battery energy storage systems to make up for the lack of commercially-available vehicle-to-home systems isn’t the only use for an old EV battery, though. For example, it’s possible to use Leaf batteries to triple the range of other EVs like [Muxsan] did with this Nissan van.

Continue reading “Vehicle-to-Grid Made Easy” →

Hacking The IKEA OBEGRÄNSAD LED Wall Lamp

May 25, 2023 by 18 Comments

The IKEA OBEGRÄNSAD is a pixel-style LED wall lamp that comes with a few baked-in animations, and [ph1p] improved it immensely with an ESP32 board and new firmware. The new controller provides all kinds of great new abilities, including new modes and animations, WiFi control, and the ability to send your own images or drawings to the panel. All it takes is desoldering the original controller and swapping in a programmed ESP32.

Hacking in a new controller provides a whole new range of capabilities.

Sadly, opening the unit up is a bit of a pain. It seems the back panel is attached with rivets rather than screws, but it will yield to a little bit of prying force.

The good news is that once the back panel is off, the inside of the OBEGRÄNSAD is very hackable. All the parts and connectors are easily accessible from where they are, and a nicely-labeled pin header makes a convenient attachment point for the new ESP32 board. There’s no need to disassemble any further once the back is off, and that’s always nice.

Going a bit smaller, we’ve also seen an IKEA LED nightlight greatly improved by a little hacking, and there are plenty more IKEA hacks where that came from.

The Voltaic Pile: Building The First Battery

May 25, 2023 by 11 Comments

In the technologically-underpinned modern world, most of us interact with a battery of some sort every day. Whether that’s the starter battery in a car, the lithium battery in a phone, or even just the coin cell battery in a wrist watch, batteries underpin a lot of what makes society possible now. Not so in the early 1800s when chemists and physicists were first building and experimenting with batteries. And those batteries were enormous, non-rechargable, and fairly fragile to boot. Not something suited for powering much of anything, but if you want to explore what it would have been like to use one of these devices, follow along with [Christopher]’s build of a voltaic pile. Continue reading “The Voltaic Pile: Building The First Battery” →

Hackaday Prize 2023: Hearing Sirens When Drivers Can’t

May 25, 2023 by 25 Comments

[Jan Říha]’s PionEar device is a wonderful entry to the Assistive Tech portion of the 2023 Hackaday Prize. It’s a small unit intended to perch within view of the driver in a vehicle, and it has one job: flash a light whenever a siren is detected. It is intended to provide drivers with a better awareness of emergency vehicles, because they are so often heard well before they are seen, and their presence disrupts the usual flow of the road. [Jan] learned that there was a positive response in the Deaf and hard of hearing communities to a device like this; roads get safer when one has early warning.

Deaf and hard of hearing folks are perfectly capable of driving. After all, not being able to hear is not a barrier to obeying the rules of the road. Even so, for some drivers it can improve awareness of their surroundings, which translates to greater safety. For the hearing impaired, higher frequencies tend to experience the most attenuation, and this can include high-pitched sirens.

The PionEar leverages embedded machine learning to identify sirens, which is a fantastic application of the technology. Machine learning, after all, is a way to solve the kinds of problems that humans are not good at figuring out how to write a program to solve. Singling out the presence of a siren in live environmental audio definitely qualifies.

We also like the clever way that [Jan] embedded an LED light guide into the 3D-printed enclosure: by making a channel and pouring in a small amount of white resin intended for 3D printers. Cure the resin with a UV light, and one is left with an awfully good light guide that doubles as a diffuser. You can see it all in action in a short video, just under the page break.

Continue reading “Hackaday Prize 2023: Hearing Sirens When Drivers Can’t” →