Kritik sah

Flickering LED tea lights are a friendly and safe alternative to having flaming little pots of wax situated around your home, but sometimes the flicker scheme leaves something to be desired. [Roger Rabbit] found a set of six such rechargeable tea lights with a base and a remote, and replaced the controller with an ATtiny85 for a more realistic flicker. When [Roger] opened up one of the candles, they found an IR sensor for the remote, a driver chip, and of course, an LED. No surprises there. After desoldering the original controller, [Roger] wired in a socketed ATtiny85 on a piece of perfboard and hooked everything back up.The coolest part of this hack might just be the fact that there’s a perfect little compartment for the new microcontroller. How about that? The Arduino code for this project is available in the Git repository , and the wonderful instruction manual is available in PDF form . Be sure to check out the brief video after the break. You like these flickering LED candl...

The Raspberry Pi line is full of capable compact computers, but they’ve never been the strongest in the bunch when it comes to graphical output. Nor have they been particularly expandable in that regard. However, that’s all beginning to change, with [Jeff Geerling] reporting success getting external GPUs to work on the Raspberry Pi 5. Unlike previous Raspberry Pis, the Raspberry Pi 5 has a less quirky implementation for its PCI Express bus. Previous editions have thrown up issues when trying to work with GPUs, but [Jeff] has found much more success this time around. He’s gotten an AMD RX 460 to work with the setup, and has got it running quite a bit of the glmark2 test regime. He’s working on a variety of other AMD cards too, but suspects NVidia parts could be harder due to some initialization issues that are proving difficult to quash. It still takes some funky adapters and a lot of work, but finally GPUs are starting to work with the platform. Keep up with his list of card trials ...

Film cameras can be complex and exquisitely-crafted masterpieces of analogue technology. But at their very simplest they need be little more than a light-proof box with a piece of film at the back of it, and some kind of lens or pinhole with a shutter. [ChickenCrimpy] adds the most basic of 35 mm cartridge to create what he calls the Minimum Viable Camera . It’s a half-frame 35 mm pinhole film camera with the simplest possible construction. It can be built from almost any flat light-proof 3 mm thick stock, though something that you can run through a laser cutter is probably ideal. Once snapped together to make to box-like structure, tape is added along the joins for light-proofing. The film is reeled from a full 35 mm cartridge to an empty one, and cranked back frame-by-frame by means of a wooden key that engages with the spindle. There’s no lens, instead this is a pinhole camera, and the shutter is a piece of the stock held on the front of the camera with bolts and butterfly nuts....

Just three years after the iconic magazine abandoned its print version and went all-digital, Popular Science is now halting its subscription service entirely . The brand itself will live on — their site will still run tech stories and news articles, and they have two podcasts that will keep getting new episodes — but no more quarterly releases. While you can’t complain too much about a 151 year run, it’s still sad to see what was once such an influential publication slowly become just another cog in the content mill. Started as a monthly magazine all the way back in 1872, Popular Science offered a hopeful vision of what was over the horizon. It didn’t present a fanciful version of what the next 100 years would look like, but rather, tried to read the tea leaves of cutting edge technology to offer a glimpse of what the next decade or so might hold. Flip through a few issues from the 1950s and 60s, and you won’t see pulpy stories about humanity conquering the stars or building a tim...

With the increase in popularity of Internet of Things (IoT) devices and their need to communicate wirelessly,  there’s been a corresponding explosion of wireless protocols to chose from. Of course there’s Wi-Fi and Bluetooth, but for more specialized applications there are some other options like Z-Wave, LoRa, Sigfox, and Thread. There’s a decent amount of overlap in their capabilities too, so when [SHS] was investigating some low-cost Xiaomi sensors it was discovered that it is possible to convert them from their general purpose Bluetooth protocol over to the more IoT-specialized Zigbee protocol instead . These combination temperature and humidity sensors have already been explored by [Aaron Christophel] who found that it’s possible to flash these devices with custom firmware . With that background, converting them from Bluetooth to Zigbee is not a huge leap. All that’s needed is the Zigbee firmware from [Ivan Belokobylskiy] aka [devbis] and to follow the steps put together by [...

Once upon a time, if you wanted to generate some waveforms, you needed to buy an expensive off-the-shelf function generator or whip up a big pile of analog electronics. Not so today, when you can grab a fast microcontroller off the shelf and have it squirt out whatever fancy waves you might desire. That’s just what [rgco] did to build this nifty arbitrary wave generator. The build improves on prior work by [rgco] with the Arduino Uno, with which they built a device that could output at 381 kilosamples per second, with each sample update taking 42 instruction cycles. Thanks to the Pi Pico’s faster clock speed and certain performance optimizations, they were able to up that to a mighty 125 megasamples per second, using the DMA and PIO subsystems to output a new sample every single clock cycle. The result is a cheap function generator you can build with a Pi Pico and a handful of resistors, which will probably cost you the grand total of $12. It readily outperforms, at least in regards...

On the surface, the electric grid might seem like a solved piece of infrastructure. But there’s actually been a large amount of computerized modernization going in the background for the past decade or so. At a large scale this means automatic control of the grid, but for some electric utility customers like [Alex] this means the rates for electricity can change every hour based on demand. By keeping an eye on the current rate, you can extract the most value from these utilities . [Alex] is located in the United Kingdom and has an energy provider whose rates can change every half hour. This information is freely available well enough in advance to download the data and display it visibly in with a NeoPixel LED ring around a clock. The colors displayed by the LEDs represent an increase or decrease in price for the corresponding time and allow him to better plan out the household’s energy use for the day. The clock uses a TinyPICO ESP32 module to gather the data and handle the clock di...

Last time, I assembled a Python object representing a Rigol oscilloscope. Manipulating the object communicates with the scope over the network. But my original goal was to build a little GUI window to sit next to the scope’s web interface. Had I stuck with C++ or even C, I would probably have just defaulted to Qt or maybe FLTK. I’ve used WxWidgets, too, and other than how many “extra” things you want, these are all easy enough to use. However, I had written the code in Python, so I had to make a choice. Granted, many of these toolkits have Python bindings — PyQt, PySide, and wxPython come to mind. However, the defacto GUI framework for Python is Tkinter, a wrapper around Tk that is relatively simple to use. So, I elected to go with that. I did consider PySimpleGUI , which is, as the name implies, simple. It is attractive because it wraps tkinter, Qt, WxPython, or Remi (another toolkit), so you don’t have to pick one immediately. However, I decided to stay conservative and stuck with...

The BBC has a long history of teaching the world about computers. The broadcaster’s name was proudly displayed on the BBC Micro, and BBC Basic was the programming language developed especially for that computer. Now, BBC Basic is back and running on a whole mess of modern platforms. BBC Basic for SDL 2.0 will run on Windows, MacOS, x86 Linux, and even Raspberry Pi OS, Android, and iOS. Desktop versions of the programming environment feature a BASIC editor that has syntax coloring for ease of use, along with luxury features like search and replace that weren’t always available at the dawn of the microcomputer era. Meanwhile, the smartphone versions feature a simplified interface designed to work better in a touchscreen environment. It’s weird to see, but BBC Basic can actually do some interesting stuff given the power of modern hardware. It can address up to 256 MB of memory, and work with far more advanced graphical assets than would ever have been possible on the original BBC Micro...

G-code is effective, easily edited, and nearly ubiquitous when it comes to anything CNC. The format has many strengths, but space efficiency isn’t one of them. In fact, when it comes to 3D printing in particular file sizes can get awfully large. Partly to address this, Prusa have proposed a new .bgcode binary G-code format. You can read the specification of the new (and optional) format here . The newest version of PrusaSlicer has support for .bgcode, and a utility to convert ASCII G-code to binary (and back) is in the File menu. Want to code an interface of your own? The libbgcode repository provides everything needed to flip .gcode to .bgcode (with a huge file size savings in the process) and vice versa in a way that preserves all aspects of the data. Need to hand-edit a binary G-code file? Convert it to ASCII G-code, make your changes, then flip it right back. Prusa are not the only ones to notice that the space inefficiency of the G-code file format is not ideal in all situat...

If you’ve got a smart home, or you just want to know how soaked your garden is getting in the winter, you might want to measure rainfall. There are a bunch of ways to go about it, and this capacitive rainmeter solution from [Magnus Thome] might just be the perfect solution you’re looking for. Like many who came before, [Magnus] had experimented with traditional resistive-based sensors using copper traces to measure water levels. As the soil moisture measuring set learned as well, corrosion tends to promise a pretty short life for these designs. Capacitive sensors, on the other hand, can be isolated from the water itself, and thus sense the levels without being subject to such degradation. [Magnus] pairs the off-the-shelf capacitive sensor with an ESP32 charged with reading it and reporting back to Home Assistant. It’s also outfitted with a heater to keep it at a constant temperature to avoid it freezing over during those cold and snowy Swedish winters. It’s a tidy way to integrate...

We’ve seen our share of light-up jewelry over the years, but for some reason — probably power — it’s almost always earrings or necklaces. So when we saw [ROBO HUB]’s LED ring , we had to check it out. It involves a bit of behind-the-scenes action in the form of a battery holder that you palm, but the end effect is quite cool. Essentially, this is a 3D printed ring with SMD LEDs painstakingly soldered together in parallel along a pair of thin copper wires. The ring itself is in two parts: a base, and a cover to diffuse and protect the LEDs. A pair of wires run out from the ring and connect to a printed coin cell holder. One thing we like about this build is the way that [ROBO HUB] handled the soldering of those tiny LEDs — by binder-clipping the ends of the wires to a piece of protoboard at just the right distance apart. Be sure to check out the build video after the break. So, is there a way to do this without having to palm a coin cell? Yes, and it involves a tiny capacitor and ...

The thing about human invention is that occasionally, two or more people think of an idea around the same time, and it’s difficult to determine who was first. Such is the case with Swatch’s Internet time, which is told in something called “.beats”. Rather than using hours and minutes, the solar day in the .beat system is divided into 1,000 parts equal to one minute in the French Revolutionary decimal time system, or 1 minute and 26.4 seconds of standard time. Swatch came up with .beats to sell their special line of .beats watches. But they weren’t the only ones to divide the solar day this way. A few months before Swatch’s announcement of .beats time, a Argentinian drummer named [Charly Alberti] came up with the same idea and created a website for it to display the current Internet time of day. The point of all this is that [Roni Bandini] has created an homage to both .beats and [Charly] in the form of a small clock . The main brain is a Seeed Studio Xiao nRF52840, with a Xiao TFT r...

[EXTREME3DPRINT] has a new version of their print-in-place tank chassis: the PiPBOT now accepts drop-in motors (in the form of 360° rotation servos), RC receiver, and battery pack to make a functional RC tank platform in no time flat. The design is entirely 3D printed with no supports needed. This new version is a paid 3D model (and it includes STEP files, thankfully) but the original proof-of-concept print-in-place tank chassis is free and remains a highly clever piece of design that really shows off what is possible when one plays to a 3D printer’s strengths. A better look at the design’s details can be found on the designer’s website , and a short video demonstrating assembly and operation is embedded below. We particularly like the attachment points on the top of the PiPBOT, which allows for securely mounting all kinds of customized payloads. Interested in this style of printable RC platform, but want something a little more accessible? If race cars are more your thing, we’d...

The fun part of security audits is that everybody knows that they’re a good thing, and also that they’re rarely performed prior to another range of products being shoved into the market. This would definitely seem to be the case with fingerprint sensors as found on a range of laptops that are advertised as being compatible with Windows Hello. It all began when Microsoft’s Offensive Research and Security Engineering (MORSE) asked the friendly people over at Blackwing Intelligence to take a poke at a few of these laptops, only for them to subsequently blow gaping holes in the security of the three laptops they examined. In the article by [Jesse D’Aguanno] and [Timo Teräs] the basic system and steps they took to defeat it are described. The primary components are the fingerprint sensor and Microsoft’s Secure Device Connection Protocol ( SDCP ), with the latter tasked with securing the (USB) connection between the sensor and the host. Theoretically the sensitive fingerprint-related ...

All of us have to deal with the looming threat of developing cancer during our lifetime, no matter how good our genetics are, or how healthy our lifestyle is. Despite major improvements to the way that we treat and even cure cases of cancer, the reality today is that not all types of cancer are treatable, in many cases there’s the likelihood that one day it will return even after full remission, and chemotherapy in particular comes with potential life-long health issues. Of the most promising new and upcoming treatments, immunotherapy, is decidedly among the most promising. With this approach, it is the body’s own immune system that is taught to attack those cancer cells, requiring little more than a few tweaks to T-cells harvested from the patient’s body, after which they’re sent on their merry cancer-killing way.  Yet as simple as this sounds, finding the right characteristics which identify the cancerous cells, and getting a solid and long-lasting immune response is a tough ch...

[DaveMakesStuff] demonstrates a great technique for 3D printing a sphere; a troublesome shape for filament-based printers to handle. As a bonus, it uses a minimum of filament. His ideas can be applied to your own designs, but his Giant Spiralized Sphere would also just happen to make a fine ornament this holiday season. Printing two interlocking parts and using vase mode ensures a support-free print that uses a minimum of filament. The trick is mainly to print the sphere in two parts, but rather than just split the sphere right down the middle, [Dave] makes two hollow C-shaped sections, like a tennis ball. This structure allows the halves to be printed in vase mode, which minimizes filament use while also printing support-free. Vase (or spiral) mode prints an object using a single, unbroken line of extruded filament. The resulting object has only one wall and zero infill, but it’s still plenty strong for an ornament. Despite its size, [Dave]’s giant ball uses only 220 grams ...