Hackaday Podcast Episode 384: OCR MOD Records, Magical PCBs, And The Gravity Of Space Stations

What did Hackaday editors Elliot Williams and Al Williams read in Hackaday last week? Probably everything, but you can tune in and hear about their favorites on this week’s podcast. They heard from lots of listeners this week, and also saw DIY projects running from a 3D-printed Stirling engine, to clogs, to LEDs.

There are some over-the-top hacks like a refit for a decades-old watch to do tap-to-pay and a — for lack of a better word — a record player that optically reads MOD files. Want to emulate an iPod? Talk to Eliza? Print a hand-operated rail car? Hackaday is the place to read about it all.

The can’t miss articles included a talk from Hackaday Europe about making magical PCBs and a not-so-brief history of space stations starting in the 1800s.

Check out the links if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download in MP3 suitable for hand-decoding.

Continue reading “Hackaday Podcast Episode 384: OCR MOD Records, Magical PCBs, And The Gravity Of Space Stations”

Building A Headless Game Boy Emulator

[Artificial-Age] has built a rather unique way to play old Game Boy games. It’s an emulator, but it doesn’t work in quite the way you might think!

Since the Game Boy is a relatively simple 8-bit machine that runs at a leisurely 4 MHz or so, it is well within the capabilities of an ESP32 microcontroller to emulate. [Artificial-Age] got an ESP32-S3 and programmed it to do just that. However, there’s a twist—there is no screen hooked up to the microcontroller, nor any buttons. Instead, the board is accessed over a WiFi access point that it hosts itself.

One then opens a web browser, which streams the emulated video and audio from the console, while accepting button inputs from your keyboard or touchscreen, depending on the platform you’re viewing the web interface on. ROMs are stored on the ESP32’s flash storage, and can be uploaded via the web interface.

It’s an interesting setup, and one that perhaps doesn’t make obvious sense at first. After all, any modern smartphone can easily emulate a Game Boy, too. However, this setup makes it easy to share the emulator with other people, who can simply check out the WiFi AP and web interface without having to download or or install anything on their own device. We’ve featured some other fun emulation projects lately, too.

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This Week In Security: Android Malware, VOIP Hijack, Signal Contact Discovery, And TeamPCP Arrests

On GitHub, [AyaanB] details buying a cheap Android TV streaming device, looking for, and finding, baked-in malware.

Multiple warnings have been issued by the FBI and CISA regarding malware on media box Android devices. Many devices have been caught participating in botnets providing residential proxies, ad-click fraud, and DDOS services. [AyaanB] sets out to discover if a $30 set-top streaming box is pre-infected with malware, and extracting it – without ever letting the device talk to the Internet or access other devices on the local network.

Picking a device named in the advisories, [AyaanB] discovered that it was, indeed, preloaded with multiple app stores and applications that wouldn’t typically make sense on a set-top TV box. After identifying the serial port test pads and obtaining a low-voltage serial adapter, they were able to gain access to the bootloader and from there dump the contents of the MMC over TFTP.

With the entire filesystem accessible out-of-body, proving it was infected with malware at the factory becomes simple: the malware is signed as a system application, baked onto the system partition of the MMC, granted SELinux exceptions to mark it as a system binary with shell privileges, and has multiple launch scripts to make sure it is executed even if partially removed. With the malware identified, [AyaanB] continues to dig through to uncover the capabilities.

By installing hooks into the low-level Android process spawning system, the malware installs hooks into every application as it is launched: even if an application isn’t trojaned already, by the time it finishes executing, it’s definitely been subverted. The functions patched and the methods used match the Vo1d botnet, which is used for account takeovers, residential proxies, free “VPN” services, and other unfriendly behavior.

Further digging into the system showed hooks for ad-click fraud, where hidden browser windows are allowed to run unthrottled and display overlays are configured to obscure ads below where the user may click. Other included tools bid in real-time ad auctions, claiming to directly publish ads to the user which may or may not be visible. To cap it all off, a root level backdoor allows botnet operators to access the systems directly and install additional tools.

Be sure to check out [AyaanB]’s writeup for more details on exfiltration methods and other malware found on the devices. Continue reading “This Week In Security: Android Malware, VOIP Hijack, Signal Contact Discovery, And TeamPCP Arrests”

RAM And EMMC Prices Are So High, Pine64 Has Stopped Linux Device Production

We all know that the price of RAM and storage has shot up due to demand from the AI industry and other factors. In most cases that means we grumble about the price, but if we really need the part we can fork out for it. [CNX Software] are reporting that rather than continue to push up their prices, Pine64 are responding to the crisis by halting production of their Linux boards for the time being.

We’ve seen online comment over the now-exorbitant cost of other boards such as a fully-loaded Raspberry Pi, and this follows in that vein. If we had to guess we’d speculate that the high process have resulted in too little in the way of sales, which considering the knock-on impact on our community if other vendors follow suit, could be concerning.

If there’s one bright spot in the current situation, it’s that for many applications where a single-board computer might be used, a microcontroller might now be a better choice for the job than something running Linux. We’re in a very different situation from that we were in when cheap Linux boards appeared, the current generation of high-power microcontrollers have significantly closed the gap between the two. Given that microcontrollers have onboard memory and storage, their immunity from the price hikes makes them even more attractive. As to Pine64, we hope that sales of their other products make up for it.


Header image: BasilicumTree, CC0.

Panoramic Photography With A Linear Scanner

Although digital photography took a big bite of the film industry’s lunch, it wasn’t able to completely eliminate the need — or desire — for photographers to use film in some situations. But digital information from a camera sensor can be manipulated to augment the natural physical capabilities of a camera in ways not really feasible for film. High dynamic range images, focus and exposure stacking, and automatic panoramic stitching. This camera takes the latter example to the extreme.

[Philo]’s proof of concept was a smartphone camera set on a chair and rotated around a room. Some software grabbed a single column of pixels as it moved and stitched them all together to form an image. This came out well enough that the idea was refined a few times, but it wasn’t until a single-line digital camera meant for imaging assembly lines was found that this really took off. Using the camera and some custom software, [Philo] was eventually able to take some of the longest panoramic images we’ve seen, using things like railways and boats as the track the camera rides on, with accelerometer data to help stabilize the image.

The results speak for themselves. There’s a bit of wobble from the movement of the various vehicles despite the accelerometer data, but given that the image is coming from a sensor meant for examining conveyor belts, it’s hard to complain. Of course, if you want to stick to film, there are panoramic film cameras available too even if they don’t quite have the reach of this digital one.

A clear tank of gel is shown against a black background. In the gel, the shape of a white plastic boat is suspended. A coarse-tipped needle dips into the top of the gel bath.

Support Bath Enables An Epoxy Benchy

There’s plenty of substances that can theoretically be extruded from a nozzle, but only a regrettably small subset of them can actually be used for 3D printing. One limiting factor is the liquid range: too high a melting point and it’s hard to reliably extrude, too low and it tends to ooze and flow once extruded. Embedded 3D printing offers a way around this: it submerges the entire print in a shear-thinning support gel which keeps liquids in place until they solidify. [Riley] of Riley’s Lab recently built such a 3D printer and used it to print in silicone and epoxy.

In place of the extruder, [Riley] mounted a mostly 3D printed syringe pump, which allowed him to squirt out almost any liquid. For a test, he printed a tardigrade model out of cream cheese. This was a good test material for several reasons: it’s cheap, easy to extrude, and holds it shape well after extrusion. Silicone and epoxy, however, won’t hold their shape, which is where the support bath comes it. This was a mixture of mineral and vegetable oil, with some fumed silica added to make it thick yet shear-thinning. This lets it contain the extruded liquid, yet flow as the extrusion needle slices through it.

For the first test, [Riley] printed a Benchy out of Sylgard 184. The outcome looked good in the bath, bar some stringing, but it seemed to have limited adhesion between layers, and disintegrated upon removal from the bath. A second test with a two-part epoxy worked much better; it also had some stringing, but it held together while the bath was washed away in isopropyl alcohol, and even seemed decently shock-resistant afterwards.

It’s great to see a hacker working on this technology; we’ve previously covered a commercial take on it, as well as some of the research that led to it.

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Running Multiple Linux Kernels Without Hypervisor

In a move that’s no doubt going to trigger a lot of confusion and nostalgia, Mklinux is back, in a sense. As the announcement makes clear, this is multikernel Linux, not microkernel Linux, which is an experimental OS designed to run the Linux kernel as a user-space server running on top of OS X’s Mach kernel.

Naming overlap niggles aside, this neo-mklinux lets multiple independent Linux kernels run simultaneously on bare metal. There is still a host kernel which handles the carving up of hardware resources to the newly spawned kernels, but unlike with a hypervisor there are no abstraction or translation layers.

In theory this should mean basically perfect isolation between kernels, which is one of the main selling points along with increased performance. Compared to running KVM guests the provided benchmarks show much lower latency, at between parity to two times faster.

A website is provided with instructions to get started, along with architectural details if that’s your thing.