Kritik sah

A healthy aquarium ecosystem requires very specific conditions, with factors like the salinity and temperature having to be just right to keep said ecosystem happy. As some species are adapted to fairly cold water, this requires the use a water chiller. Recently [The Blunt Oracle] modified one of these aquarium-focused chillers with a much better controller to make it both more accurate and potentially more efficient as well. The target for the surgery was a generic Shanhuchong Y-160 chiller that after a brief teardown turned out to use an STC-1000 style controller. The biggest disadvantage with this unit is probably that it just has one temperature probe, which monitored the temperature of the heat exchanger rather than that of the chilled water tank. This controller was replaced with a Wi-Fi-equipped Elitech ECS-974T sourced for $50 off AliExpress that uses the same 71 x 29 mm form factor. Following that it was just a matter of some creative rewiring – as shown in the top ima...

If you just want to play with a Rubik’s Cube, you can simply buy one from a local toy store. If you want to build one, you could 3D print something and put it together yourself. But what if you want to make lots of Rubik’s Cubes? Then, you might go down the road that [EngBroken] just walked. What started as a fun reverse-engineering project would lead to an 8-month journey to reproduce Rubik’s Cubes from scratch using injection molding. [EngBroken] started by identifying the basic pieces that make up the cheap cube they bought, including the center core, the edge pieces, and the corner pieces. Parts were then recreated in CAD, and [EngBroken] then set about designing and milling injection molds out of 6061 aluminium to make the parts. Amusingly, to get the correct colors for the separate parts of the cube, [EngBroken] made the curious decision to mix cut-up pieces of 3D printer filament with clear ABS pellets to tint it as needed. Parts were then assembled with UV-c...

Do you want to go back to an era when Windows was… simpler? Back when things worked, before the AI and the bloat took over your hard drive and RAM space in equal measure? You might like to give Classic 7 a spin (via The Register ). From the drop, we should state that Classic 7 is not Windows 7 at all. Instead, it’s a reskin of Windows 10, specifically, the IoT Enterprise LTSC version. This is a particularly attractive version of Windows 10, as Microsoft has promised long-term support in terms of security updates until 2032. It also strips out annoying consumer-focused bloat like the Xbox gaming overlay and Cortana, and it eliminates forced feature updates that have become the norm in modern Windows installs. Combine all those niceties with the clean and simple feel of the recreated Windows 7 interface, and you have a beautiful operating system that has everything you need and nothing you don’t. There are, of course, some hurdles to jump over; you’d need to fin...

Will your next project be a success? Only time will tell, but if you build [gokux]’s tiny ESP32 fortune cookie , we predict that, at the very least, there won’t be any crumbs involved. After briefly entertaining the idea of shoving an ESP32 in a standard fortune cookie, [gokux] thought better of it and came up with this instead. Once shaken, this small gadget displays a fortune on its e-paper screen. It can store over 3,000 fortunes and works entirely offline, so you’re never without an oracle. Inside you’ll find a Seeed Xiao ESP32-S3 Plus and a matching e-paper display board. [gokux] is detecting the shakes with an MPU-6050 accelerometer, and powers everything with a small Li-Po pouch. If you tire of the fortunes that shake out, the small buttons on the left side will get you into the other modes, which are a dice roller and a coin flipper. Again, you just shake the thing until you get what you want. Be sure to check it out in the video after the break. Want...

[Jankbu] needed a new computer, but had little interest in purchasing a modern laptop off the shelf. Instead, it was time to build a cyberdeck with a neat modular design to suit his exact needs. The heart of the build is a Raspberry Pi 5, which provides a good amount of computing power for regular tasks. It’s wrapped up in a 3D-printed enclosure with rail mounts on the back, along with a NOS 450 TKL mechanical keyboard, offering full-travel keys in a compact layout. The 10.1″ IPS touchscreen display is mounted on sliding rails to cover the keyboard when it’s not needed. A smattering of buttons live around the screen, in a manner akin to so many industrial controllers. On either side, the deck has large grab handles, with one side featuring custom horizontal and vertical scroll controls, while the other rocks a trackball.  Power is via NP-F batteries, which are more commonly used to run Sony camcorders. Unlike so many cyberdecks, [Jankbu] didn’t just build the d...

Circa 2015 or so, it seemed like you couldn’t move a finger without being bombarded with ads and articles about ‘smart homes’ and the ‘internet of things’ — all of which would make our lives so much easier and more automated. Fast-forward a decade and this dream has mostly evaporated along with many of the players in the space. Why this happened is the topic of a recent video by [Caya] . An interesting bit of context that the video starts off with is that home automation really kicked off back in 1975, when the X10 protocol and related devices using power lines for signaling began being sold. These fully integrated solutions generally worked reasonably well, but what all changed when the IoT and ‘smart home’ craze kicked off and brought with it an explosion of new standards. Over the past decade we have seen the concept of a ‘smart home’ collapse into a nightmare of abandoned IoT devices, subscription services, forced ads, ...

FDM 3D printing is fairly messy on a molecular scale, with the filament being heated up to temperatures high enough to melt it, which produces ultra-fine particles (UFPs) and volatile organic compounds (VOCs) in addition to the new plastic item on the build plate. Recently [Simon Pow] got somewhat worried about this pollution considering that he spends a considerable amount of time in the same room as FDM printers, sharing air. While there is a lot of context within the topic, it’s notable that even ‘low risk’ PLA already emits formaldehyde , a group 1 carcinogen. Studies like this 2022 one by [Taehun Kim] et al. on formaldehyde, PM10 and PM2.5 show that common filaments like PLA, ABS and TPU score pretty bad here, even compared to the often maligned resin printing, also in the study. Having good ventilation in a room helps a lot, but it doesn’t reduce the levels to zero. As noted by [Simon], PETG is much better in the VOC area, while TPU emits siloxanes , so...

Lots of music events these days hand out various glowing tchotchkes that flash and sync up with the performance. [Tony Goacher] has whipped up his own badges that can do just that, all without needing any sort of pairing or infrastructure to speak of. The CrowdClock badges each feature a ring of 16 addressable RGB LEDs. Running the LEDs is an ESP32 microcontroller, which has lots of neat wireless capability baked in from the factory. [Tony] decided to leverage the ESP-NOW wireless communication protocol to enable each badge to broadcast its current local clock tick. Each device also listens out for clock ticks from other badges in the area, and updates its current clock tick value if it receives a higher one from another badge. This behaviour allows a bunch of badges within radio range to all sync up automatically in short order, and then run their LED sequences in sync. There’s no need for a master designation or anything, the devices just all sync to whichever badge has the hig...

In a recent video  [Saša Karanović] revisits the DIY filament dryer that he gave a shot a couple of years ago. Back then he reused an existing filament dryer, adding a custom controller and such to improve its performance. This technically-not-fully-DIY dryer got some feedback since then, and thus the V2 version is an example of how to better DIY such a dryer, including a custom PCB and a GitHub project for all the details. Those who just want to dive into the documentation for assembly and the BOM can look at the available documentation . At its core the whole assembly consists of some kind of container like the shown 5L food storage type, along with an SHT30 temperature and humidity sensor and 100K NTC temperature sensor. These connect to the controller board which then switches on or off the 12V polymide resistive heater. One thing that could be improved here is that the saturated warm air has nowhere to go. This is a common issue with filament dryers and why it’s recommende...

A potentiometer is a simple electrical device that allows resistance to be varied at will. Most everyone in the electronics field is intimately familiar with how they work on a fundamental level. Of course, we all had to be taught once, though, and a great way to do that would be with a teaching tool like the one [DiscoLapy] built . What you’re looking at here is a very simple potentiometer that bares its function for all to see. It consists of a 3D printed base and knob, which form the mechanical part of the device. A paper track is then laid on top to act as the main resistive element, once properly covered with graphite from a regular old pencil. From there, it’s as simple as adding the necessary contacts and wiper to the device, and you’ve got a potentiometer sitting in front of you. What’s great about this build is that it’s very intuitive. Just by looking at it or putting it together, you get a straightforward understanding of everything that’...

Magnetic fields are all around us. We can’t really feel or see them ourselves, per se, but we can map them with the right hardware, like this device built by [edosari50]. The build uses an ESP32 microcontroller, which is built on to a board with an integrated 4.3″ touchscreen LCD. It’s paired with an Arduino Nano, which does the work of actually talking to a pair of EMS100 Fluxgate magnetic sensors. The slower, less capable Arduino handles the low-level chatter and then passes the readouts to the ESP32 over a UART connection. Power is courtesy of a pair of 18650 lithium-ion cells, and a XL4005 DC-DC converter. A lithium-ion charging module is on hand to keep the batteries topped off safely.  Scan results are visualized on the device itself using a heatmap representation, and can also be exported to SD card for later analysis if so desired. Unless you’re in the geological field or otherwise hunting for stuff underground, this probably isn’t a tool you...

Even [maurycyz] doesn’t think it is a good idea, but it is possible to use an AVR 8-bit CPU to serve web pages . Of course, it is a vastly simplified web server, but it does serve pages — OK, technically just one page  — to the public Internet. Working backward, it is fairly easy to get the microcontroller to note an HTTP request and then simply spit out a prerecorded HTTP response to provide the page. The hard part is connecting the little processor to the network. The server is dead simple, just a CPU and a scant number of components like filter caps and LEDs. The trick is to use SLIP , an ancient protocol used to connect dial-up modem terminals to the network. Linux supports SLIP, so the MCU connects to a Linux computer via SLIP. Then the Linux computer uses WireGuard to network with the remote web server that serves [maurycyz’s] site. The SLIP implementation assumes that IP packets aren’t fragmented, which is normally true these days. TCP was a bit mo...

One of the problems with good science fiction is that it introduces us to all kinds of cool devices that we can’t actually have in real life. [Huy Vector] has tried to fix that a little with this fantastic smartwatch build inspired by everybody’s favorite wrist computer from the Fallout series . The build is based around a Xiao ESP32-S3 board, which hosts the capable microcontroller and has all that useful wireless connectivity built in. It’s hooked up to a MAX30102 heart rate sensor to collect the wearer’s vital signs, as well as a 1.54″ LCD screen for displaying the fantastic Pip Boy themed interface. Power is courtesy of a small lithium-ion cell tucked in behind the display. A little copper tubing and brass hardware helps tie everything together, with the latter serving as capacitive touch points for controlling the device. A simple leather watch strap completes the build. It’s a bit of a diversion from the classic Pip Boy design, in that it...

Everyone loves those rather bouncy wooden lounge chairs that got popularized by a certain Swedish seller of furniture, but as tough as they are, the laminated wood can still break at some point. The chair that [John’s Furniture Repair] got in for repair had cracked right around where a bolt hole had been drilled, apparently creating a weak spot that over the years turned into a crack. The way to fix this issue is to recreate the one piece of curved, laminated wood as demonstrated in the video. This starts with tracing the contours of the original part on a piece of MDF, which then gets doubled up by a second plate of MDF. After cutting out the contours this then creates the two halves of a mold for the laminated part. Next is preparing the layers of wood that will become the new part, making sure to keep the same final thickness as the original. With everything glued up the layers are put into the mold, clamped down and the glue left to dry. Finally, the part is freed from th...

Like many people who read Hackaday, we are fairly fluent in a number of computer languages, but we have to admit it is easier to pick up languages that look like they group with things like Fortran. Sure, modern languages have all sorts of features, but the idea that you have a text file that executes in some order, variables, statements, and so on runs through most popular languages, but not all of them. Lisp and its variants are a different way of looking at things. And then there’s Prolog. [Alexander Petros] has an interesting way of explaining Prolog as a Pokémon game . Prolog was “the next big thing” when AI meant expert systems. It is more of a specialized database where you define facts and rules that the computer can infer answers to queries. For example, if the facts say that Paul and Anna both have Mary as a parent, and a rule says that people with the same parent are siblings, then a query asking whether Paul and Anna are siblings will indicate that they ar...

Electroplating 3D prints is a good way to get a pretty nice coating on even a basic PLA part, but generally you’re expected to dunk the entire part into a big vat with electrolyte after coating it with the requisite conductive paint layer. This is great for small parts, like a ring you’d put on a finger, but gets rather silly when it’s a much larger part, such as the one in [Hendrik]’s recent video. Out of curiosity he tried to see whether rotating the part through a much smaller vat would still get you an even coating , or not. Perhaps ironically this process required building a custom vat out of acrylic, as well as an entire rig to hold up the part and gently rotate it. This highlights the main disadvantage of this approach, in that unless you’re doing a small production run or otherwise get to re-use the rig a lot it’s a lot of extra effort. That said, the rotation is controlled by an ESP32 and a stepper motor along with a requisite stepper drive...

You could make a clock with three hands spinning about nested central shafts. If you did that, we probably wouldn’t publish it on Hackaday unless you really found a way to make it interesting. Make a clock out of voltmeters, however, and that usually catches our eye. [lcamtuf] has done just that . The heart of the build is an AVR128DB28 microcontroller, an 8-bit microcontroller that is still currently in production. It runs at 8MHz, and drives a series of three Baomain 65C5 voltmeters to display hours, minutes, and seconds. Each has a custom printed face with the correct number of 13 or 61 divisions as needed. The voltmeters are driven by a continuous stream of 1-bit pulses with a software-controlled duty cycle determining exactly how far the needle moves. Yes, it’s using simple pulse width modulation, coded by hand by [lcamtuf] to do the job. All the components are wrapped up in a beautiful wooden case, with delicately kerf-bent panels to create the attractive curved lines...

Most consumer-grade night vision devices are basically a standard camera without the usual filter to block near infrared (NIR) light, which are then paired with a NIR light source that’s not visible to the human eye. Unlike the passive night vision provided by a photomultiplier tube, these can’t resolve objects beyond the beam of their illumination source. On the other hand, if, as [Project 326] did , you use an infrared laser to illuminate the scene, you can still get a very long range out of these devices. [Project 326]’s device consists of a previously-built reflecting telescope focusing a distant scene in to a webcam with the infrared filter removed, with the infrared laser illuminating the scene. Finding a suitable laser took some effort: the first option, a secondhand fiber-coupled industrial laser, was accidentally over-volted and destroyed during testing. The second had a fiber output which proved extremely hard to terminate, and a third laser couldn’t be collimated cor...

If you’ve got a Bambu Labs printer, it’s usually pretty straightforward to keep an eye on it via the onboard display or the various apps the company has released. However, if you want a dedicated display somewhere remote from your printer, you might like this build from [Keralots]. The project is based on an ESP32-S3 Super Mini, paired with a 1.54″ TFT display with a 240 x 240 resolution. It’s set up to talk to Bambu Labs printers over MQTT with TLS. It harvests status data and uses it to display a real-time dashboard with critical printer parameters display on arc gauges. There’s also plenty of live stats to pore over, as well as buzzer notifications if you want auditory alerts about what is going on. It’s possible to use with just about any Bambu Labs printer with a Bambu Cloud access token; otherwise, you can tinker with LAN Direct connections on certain models, but you might need to enable Developer Mode depending on your rig. If you want to mon...

Sure, you can buy a portable monitor off your favorite e-tailer, but with perfectly fine displays in devices like laptops being tossed out every single day, why not repurpose those instead? That’s what [ScuffedBits] recently did with the panels  pulled from some old laptops. A good question with any such salvaged panel is just how practical it is to still use them, with disqualifying features being things like passive-matrix TFTs as well as the use of CCFL backlighting as with one of the three panels demonstrated in the video. Looking up the model number of a panel on a site like panelook.com will tell you the display technology, resolution and other important details before you decide to commit to using it. If it’s using a LED backlight and at least Low-Voltage Differential Signaling (LVDS) but ideally eDP you can likely find a cheap driver board for it that has all the requisite inputs like HDMI and power. The hardest part is probably the case for the panel, as they...

To start things off, we’d like to extend a special thanks to everyone who joined us for Hackaday Europe this weekend in Lecco, Italy . It was 48 hours of fascinating talks, incredible badge hacks, and some of the greatest company you could hope for. For those who couldn’t make it in person, we didn’t forget you — expect to hear more about what went down once we get a chance to catch our collective breath. That’s not the only thing to keep an eye out for in the coming days. This is your reminder that Amazon will be officially ending support for older Kindles in a few days . After May 20th, any of the megacorp’s e-readers that were introduced before 2012 will be persona non grata, so you should plan accordingly. The biggest change is that these older devices won’t be able to buy digital books from Amazon, but you can still use them offline, and the fantastic Calibre makes it a breeze to load up content from other sources. To be perfectly honest...

Streaming services have enabled many of us to have easy access to the world’s media library at the touch of a screen, but [Coconauts] thinks we’ve lost something along the way. To bring some intentionality back to the listening experience, they built an NFC record player called Minilos . Like a normal record player, Minilos requires the user to select an album to play on the machine. These were originally decorative coasters with records printed on them, so they are much smaller than even a 45. Each one features an NFC tag that instructs ESP32 microcontroller hidden in the device to play the requested song. Once placed on the record player, it will then play through that album and come to a stop. In [Coconauts]’s current setup, the ESP32 is connected to a Home Assistant server which then instructs a Google Speaker to play the requested song via Spotify, although we could easily imagine this being used to play music directly from an SD card or other digital storage de...

When you visit certain large sites in Firefox or Safari, the browser may detect your visit and change its behavior. It could be as simple as lying about its identity, or it may totally change how it renders the page. But according to a post by [Den Odel], this isn’t a conspiracy between browsers and big Internet — rather, it is a byproduct of Chrome’s dominance . Here’s how it goes. Chrome puts out a new feature and everyone rushes to implement it on their site. Maybe the new code breaks other browsers. Maybe the other browser supports the feature, but the website doesn’t detect it correctly or is unaware. Maybe it just relies on some quirk of Chrome. Regardless, Firefox and Safari will change to match the site rather than mess up the user’s experience. If you want to check it out, Firefox will show you what it does and let you disable specific fixes if you visit the about:compat URL. For Safari, you’ll have to read code from a file named quir...

Given that some of the more famous demos were by Honda and Tesla, you might be forgiven for thinking you need pockets as deep as a car company to get into humanoid robotics — and maybe that was true once, but now Asimov v1 is here . It doesn’t have a positronic brain, and you’ll have to code in the Three Laws for yourself, but at least you have the freedom to, because Asimov is open source.  It’s not exactly cheap: the kit version comes with a target price of $15,000 USD, but they do provide the Bill of Materials on the GitHub repository so you can try and hunt down some deals. Still, compared to the millions poured into these sorts of robots in the early days, we have to consider it accessible. With 25 total degrees of freedom, you’ll have to source a lot of actuators, but at least the onboard compute will be easy to get. Rather than begging CERN for spare positrons, you’ only need a Raspberry 5 and a Radaxa CM5. No word on if this robot can write ...