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ESP-SDR Can Now Transmit

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Well, that was fast! Last week, we reported on two apparently simultaneous hacks using the 2.4 GHz radio inside many ESP32 variants that enabled raw access to the radio samples, turning it into a listen-only software defined radio (SDR) platform. Listen only? That’s only half of the SDR story. Last weekend, [Murmel] got started fixing that, and released an early early version of ESP32 firmware that can also transmit , and got it working with gqrx. He demos it by communicating using a Hellschrieber mode of his own devising between an S3 and a C6. And he didn’t stop there, either. He’s working on 802.15.4 modulation at the moment, which means that maybe soon your ESP32 will speak ZigBee. This is all in the roughly 2.4 GHz band, but Espressif’s API suggests that the radios will tune down as low as 100 MHz, although we can hardly imagine that the filters are tuned to make that particularly effective. Still, it’s clear that the boundaries on the ESP-SDR are just starting to get pushed. ...

Using a Waffle to Check the Health of your Wii U’s NAND Flash

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Game consoles tend to have a weak spot or two that will take certain units out sooner than they would due to normal parts aging. In the case of the Wii U it’s the eMMC storage IC with the console’s firmware and any user data that likes to keel over, with the SK Hynix variant reportedly developing faulty cells much sooner than the Samsung and Toshiba chips. If you want to check the health of these eMMC ICs in your Wii U, you can do so easily now with the Wafel Installer project by [zer00p]. This doesn’t take much more than navigating to the wafel.xyz URL on the Wii U to launch the installer on any (unmodified) Wii U, or alternatively starting it from an SD card if you’re running a homebrew-enabled console. This can also install the Stroopwafel CFW, ISFSax and the Aroma homebrew environment, but the NAND testing option in the installer’s menu is what you want to select if you’re not into homebrew or have already cracked open the console for said sweet...

Using Kirigami Techniques to Make Functional Designs

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The variant of origami called kirigami (‘cut paper’ in Japanese) also starts off with a sheet of paper, but it allows for cutting the paper to increase the number of shapes that you can create. It is this technique that [Matthew Lim] used to create a number of three-dimensional designs that can convert between a flat configuration and some kind of functional object without any bolts, glue or similar. These include everything from a phone grip to a pretty sizeable side table. The video starts with an interesting demonstration of how to fold an origami crane that has a smaller crane on its back. This is documented in a 1797 book on the many ways to fold a crane, with one of the first known instances where cuts are made in the single sheet of paper, which becomes the second, much smaller crane. The same book extends that idea into making an origami grid that can fold into a grid of cranes after making a series of cuts. Later this form of origami got the name ‘kirigami...

WiFi Router Does Software-Defined Radio

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Perhaps the most famous of software-defined radios is the RTL-SDR, which is very cheap because it’s a digital TV receiver that’s been pressed into service delivering raw I and Q data streams. But the RTL-SDR is certainly not the only chipset that can do this, and today we have a new one. The MediaTek MT7996 radio chip in the Gemtek W1700K WiFi 7 router can serve as a very competent SDR receiver, and here’s [h0m3us3r] with the code to make it stream over Ethernet to a Linux machine with a web server, through the device’s SoC . The radio works on the 2.4, 5, and 6 GHz bands, depending upon which version of the device — and thus which radio chip — you have. These may not be entirely useful to many who use lower bands, and given that a similar hack has been found for ESP32 radios on 2.4 GHz it’s likely a demand will arise for a receive up-converter. Until then, you can look at WiFi packets in a waterfall view to your heart’s content. Since...

The Prusa Core One+ INDX, a Troubled Multi-Extruder Upgrade?

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The Prusa Core One+ INDX is an interesting upgrade to the base FDM printer by Prusa, featuring eight independent extruders – hence the INDX – that in theory should allow for multi-material and multi-color printing with very little purge waste. As [Thomas Sanladerer] found out during his experiences with this printer, there are a lot of issues with this machine , including the ability – or lack thereof – to print with non-Prusa filament. Although the premise is solid, with a claimed 0.013 grams of purge waste per color or material change along with pretty nice dual-gear Bondtech extruders, the first major hurdle that [Thomas] encountered was that the mandatory calibration sequence on starting a print is designed to only work with Prusa’s own filament and its specific material properties. This resulted in an inability to print with Voxel PLA until [Thomas] removed this sequence manually from the g-code. This is when [Thomas] found out that the entire print...

The Hexa-Bouncer May Be The Most Overengineered Thing You See This Week

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Sometimes, you want to build a simple project– the minimum viable product that solves your problem and nothing else. Other times you might be feeling a little extra, and want to use oodles of machined aluminum, six steppers, two cameras, a Teensy and a PC with a GPU just to bounce a ball. That’s the mood behind [T-Kuhn]’s hexa-bouncer, a Stewart Platform on steroids.  You can read all about it on his blog or witness it in action in the video below .  Trust us, really have to see it in action. The six stepper motors connected to planetary gearboxes each drive an arm. Ingenious linkages allow the steppers to control a ping-pong paddle in every axis of rotation and translation. A Teensy 4.0 coordinates those steppers, but the marching orders are coming from a PC where a Unity application — available on GitHub — is performing Inverse Kinematics using the two cameras to track the ball in 3D. You might imagine a GPU comes in handy there. Both the article and ...

DECing Out the Homelab with an AlphaServer 2100

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Retrocomputer enthusiasts have a bad rap as nerds who just want to play old video games. There’s some truth in this, but the reality is that we’re nerds who want to do all sorts of things with old hardware — everything from consoles to servers. Servers like the DEC AlphaServer 2100 [derelictelectronics] picked up at Vintage Computer Festival Midwest this year. He was kind enough to record a tour for those of us who missed seeing these early Alpha machines in their heyday. DEC did sell these units with multiple-CPU reports from the get-go, but the [derelictronics] particular model has  a single CPU board carrying a 64-bit Alpha RISC processor. This machine from 1994 dates to near the height of the RISC wars when it seemed everyone needed to have their own high-end architecture, all of them RISC. While the machine could host up to 2GB of RAM, the example [derelictelectronics] found only has 256 MB, which was still not a small number for 1994! He does get the machine ...