This Week In Security: National Backdoors, Web3 Backdoors, And Nearest Neighbor WiFi

December 6, 2024 by 16 Comments

Maybe those backdoors weren’t such a great idea. Several US Telecom networks have been compromised by a foreign actor, likely China’s Salt Typhoon, and it looks like one of the vectors of compromise is the Communications Assistance for Law Enforcement Act (CALEA) systems that allow for automatic wiretapping at government request.

[Jeff Greene], a government official with the Cybersecurity and Infrastructure Security Agency (CISA), has advised that end-user encryption is the way to maintain safe communications. This moment should forever be the touchstone we call upon when discussing ideas like mandated encryption backdoors and even the entire idea of automated wiretapping systems like CALEA. He went on to make a rather startling statement:

I think it would be impossible for us to predict a time frame on when we’ll have full eviction

There are obviously lots of unanswered questions, but with statements like this from CISA, this seems to be an extremely serious compromise. CALEA has been extended to Internet data, and earlier reports suggest that attackers have access to Internet traffic as a result. This leaves the US telecom infrastructure in a precarious position where any given telephone call, text message, or data packet may be intercepted by an overseas attacker. And the FCC isn’t exactly inspiring us with confidence as to its “decisive steps” to fix things. Continue reading “This Week In Security: National Backdoors, Web3 Backdoors, And Nearest Neighbor WiFi” →

Hacked Ultrasonic Sensors Let You See With Sound

December 6, 2024 by 13 Comments

If you want to play with radar — and who could blame you — you can pretty easily get your hands on something like the automotive radar sensors used for collision avoidance and lane detection. But the “R” in radar still stands for “Radio,” and RF projects are always fraught, especially at microwave frequencies. What’s the radar enthusiast to do?

While it’s not radar, subbing in ultrasonic sensors is how [Dzl] built this sonar imaging system using a lot of radar principles. Initial experiments centered around the ubiquitous dual-transducer ultrasonic modules used in all sorts of ranging and detection project, with some slight modifications to tap into the received audio signal rather than just using the digital output of the sensor. An ESP32 and a 24-bit ADC were used to capture the echo signal, and a series of filters were implemented in code to clean up the audio and quantify the returns. [Dzl] also added a downsampling routine to bring the transmitted pings and resultant echoes down in the human-audible range; they sound more like honks than pings, but it’s still pretty cool.

To make the simple range sensor more radar-like, [Dzl] needed to narrow the beamwidth of the sensor and make the whole thing steerable. That required a switch to an automotive backup sensor, which uses a single transducer, and a 3D printed parabolic dish reflector that looks very much like a satellite TV dish. With this assembly stuck on a stepper motor to swivel it back and forth, [Dzl] was able to get pretty good images showing clear reflections of objects in the lab.

If you want to start seeing with sound, [Dzl]’s write-up has all the details you’ll need. If real radar is still your thing, though, we’ve got something for that too.

Thanks to [Vanessa] for the tip.

Non-Planar Fuzzy Skin Textures Improved, Plus A Paint-On Interface

December 6, 2024 by 4 Comments

If you’ve wanted to get in on the “fuzzy skin” action with 3D printing but held off because you didn’t want to fiddle with slicer post-processing, you need to check out the paint-on fuzzy skin generator detailed in the video below.

For those who haven’t had the pleasure, fuzzy skin is a texture that can be applied to the outer layers of a 3D print to add a little visual interest and make layer lines a little less obvious. Most slicers have it as an option, but limit the wiggling action of the print head needed to achieve it to the XY plane. Recently, [TenTech] released post-processing scripts for three popular slicers that enable non-planar fuzzy skin by wiggling the print head in the Z-axis, allowing you to texture upward-facing surfaces.

The first half of the video below goes through [TenTech]’s updates to that work that resulted in a single script that can be used with any of the slicers. That’s a pretty neat trick by itself, but not content to rest on his laurels, he decided to make applying a fuzzy skin texture to any aspect of a print easier through a WYSIWYG tool. All you have to do is open the slicer’s multi-material view and paint the areas of the print you want fuzzed. The demo print in the video is a hand grip with fuzzy skin applied to the surfaces that the fingers and palm will touch, along with a little bit on the top for good measure. The print looks fantastic with the texture, and we can see all sorts of possibilities for something like this.

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A Hundred Year Old Solid State Amplifier

December 5, 2024 by 21 Comments

Conventional wisdom has it that the solid state era in electronics began in 1948 with the invention of the transistor, or if you wish to split hairs, with the 1930s invention by the Russian [Oleg Losev] of an early form of tunnel diode. But there’s an earlier amplifier technology that used a solid state circuit which is largely forgotten, and [AWA Communication Technologies Museum] has featured it in a new video. We’re talking of course about the carbon microphone amplifier, a piece of telephone technology which made its way into consumer electronics.

The carbon microphone is a container of loosely packed carbon granules acted upon by a diaphragm. Vibrations from sound compress and decompress the granules, changing the electrical resistance of the carbon. It was the standard microphone used in telephone handsets for most of the twentieth century. Being a resistor it can be placed in a potential divider circuit that produces some significant voltage swings, so when the vibrations come from a high-impedance earpiece it can make an amplifier. It’s not a very good amplifier, it has lousy bandwidth, distortion, and noise characteristics, but it was just about good enough to be paired with a 1920s crystal set. In the video below the break we see a variety of the devices, and even hear them in action sounding very tinny indeed. At the time it must have seemed miraculous to be at the forefront of the new technology though, and we can’t help admiring some of the construction intricacies.

Carbon microphone amplifiers may be rare today, but for all that we’ve touched on them before.

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Unconventional Oil Production, All You Need To Know

December 5, 2024 by 48 Comments

It’s fair to say that climate change is perhaps the greatest challenge facing our planet, and while much attention is directed towards solutions to the problems it presents, perhaps there’s less attention given to the the other side of the equation in the hydrocarbon industry. For example we all think we know something about hydraulic fracking wells, but how much do we really know?

[John Thurmond] is a geologist who has recently completed a long career in the oil industry, and he gave an informative talk on the matter at the summer’s EMF Camp in the UK. It makes for an interesting watch, as he leads the viewer through the process in detail, before discussing what should and shouldn’t cause worry.

We learn that fracking has two parts: first the hydraulic fracking itself, and then the re-injection of the toxic fracking well water released from underground along with the oil or gas. It seems the water released from the rocks a 10,000 ft depth contains all manner of toxic and even radioactive compounds, and the usual means of disposal is to inject it back into the ground at a much lower depth. He makes the point that while the hazards associated with the fracking are low, those of the re-injection are high.

The talk finishes up with perhaps the most interesting point, by looking at the nature of opposition to fracking, or indeed any other controversial development. Such things are inevitably surrounded by a swirling mess of half-truths, and his point is that identifying those easily deflected as not true is key to understanding the whole thing. It’s presented from an expert and factual perspective that’s so often lacking in this arena, and thus we think it’s worth a watch.

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Brain on a chip setup with a hand and a dropper

Gray Matter On A Chip: Building An Artificial Brain With Luminol

December 5, 2024 by 11 Comments

Ever wondered if you could build a robot controlled by chemical reactions? [Marb] explores this wild concept in his video, merging chemistry and robotics in a way that feels straight out of sci-fi. From glowing luminol reactions to creating artificial logic gates, [Marb]—a self-proclaimed tinkerer—takes us step-by-step through crafting the building blocks for what might be the simplest form of a chemical brain.

In this video, the possibilities of an artificial chemical brain take centre stage. It starts with chemical reactions, including a fascinating luminol-based clock reaction that acts as a timer. Then, a bionic robot hand makes its debut, complete with a customised interface bridging the chemical and robotic worlds. The highlight? Watching that robotic hand respond to chemical reactions!

The project relies on a “lab-on-a-chip” approach, where microfluidics streamline the processes. Luminol isn’t just for forensic TV shows anymore—it’s the star of this experiment, with resources like this detailed explanation breaking down the chemistry. For further reading, New Scientist has you covered.

We’ve had interesting articles on mapping the human brain before, one on how exactly brains might work, or even the design of a tiny robot brain. Food for thought, or in other words: stirring the gray matter.

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How Corroded Can A Motherboard Be?

December 5, 2024 by 9 Comments

We will admit it. If we found a 386 motherboard as badly corroded as the one [Bits und Bolts] did, we would trash it—not him, though. In fact, we were surprised when he showed it and said he had already removed most of it in vinegar. You can check the board out in the video below.

There was still a lot of work to do on both the front and back of the board. The motherboard was a Biostar and while it isn’t as dense as a modern board, it still had plenty of surface mount parts jammed in.

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