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Showing posts from October, 2025

When USB Charger Marketing Claims are Technically True

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The 600W is not the output rating, despite all appearances. (Credit: Denki Otaku, YouTube) We have seen many scam USB chargers appear over the years, with a number of them being enthusiastically ripped apart and analyzed by fairly tame electrical engineers. Often these are obvious scams with clear fire risks, massively overstated claims and/or electrocution hazards. This is where the “600W” multi-port USB charger from AliExpress that [Denki Otaku] looked at is so fascinating , as despite only outputting 170 Watt before cutting out, it’s technically not lying in its marketing and generally well-engineered. The trick being that the “600W” is effectively just the model name, even if you could mistake it for the summed up output power as listed on the ports. The claimed GaN components are also there, with all three claimed parts counted and present in the main power conversion stages, along with the expected efficiency gains. While testing USB-PD voltages and current on the USB-C por...

Cold Sensor, Hot Results: Upgrading a DSLR for Astrophotography

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When taking pictures of the night sky, any noise picked up by the sensor can obscure the desired result. One major cause of noise in CMOS sensors is heat—even small amounts can degrade the final image. To combat this, [Francisco C] of Deep SkyLab retrofitted an old Canon T1i DSLR with an external cooler to reduce thermal noise , which introduces random pixel variations that can hide faint stars. While dedicated astrophotography cameras exist—and [Francisco C] even owns one—he wanted to see if he could improve an old DSLR by actively cooling its image sensor. He began with minor surgery, removing the rear panel and screen to expose the back of the sensor. Using a sub-$20 Peltier cooler (also called a TEC, or Thermoelectric Cooler), he placed its cold side against the sensor, creating a path to draw heat away. Reassembling the camera required some compromises, such as leaving off the LCD screen due to space constraints. To prevent light leaks, [Francisco C] covered the exposed PCBs an...

Build A 3D Printed Tide Clock So You Know When The Sea Is Coming To Get You

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The tides! Such a unique thing, because on Earth, we don’t just have oceans full of liquid water—we also have a big ol’ moon called Moon to pull them around. You might like to keep track of the tides; if so, this tide clock from [rabbitcreek] could come in handy. The motions of the tides are moderately complex; it was in the late 19th century that Sir William Thomson figured out a reasonable method to predict the tides mathematically and with a mechanical contrivance of his own design. These days, though, you don’t need pulleys and ropes to build a tide clock; you can just use electronics for display and the NOAA API to get the information you need. [rabbitcreek’s] build is based around the Xiao ESP32 S3, which is charged with using its Wi-Fi connection to query NOAA up-to-date tide height data. It then uses this information to drive the position of a servo, installed inside a 3D-printed housing. The servo rotates a little red Moon indicator around a central Earth, with our home pla...

Pulling a High Vacuum with Boiling Mercury

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If you need to create a high vacuum, there are basically two options: turbomolecular pumps and diffusion pumps. Turbomolecular pumps require rotors spinning at many thousands of rotations per minute and must be carefully balanced to avoid a violent self-disassembly, but diffusion pumps aren’t without danger either, particularly if, like [Advanced Tinkering], you use mercury as your working fluid . Between the high vacuum, boiling mercury, and the previous two being contained in fragile glassware, this is a project that takes steady nerves to attempt – and could considerably unsteady those nerves if something were to go wrong. A diffusion pump works by boiling a some working fluid – usually silicone oil – and creating a directed stream of vapor. The vapor molecules collide with air molecules and impart momentum to them, drawing them along with the vapor stream into a condenser. The condenser liquefies the working fluid, while a backing vacuum pump just past the condenser removes the ...

Implementing a Kalman Filter in PostgreSQL to Smooth GPS Data

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Usually databases are treated primarily as fairly dumb data storage systems, but they can be capable of much more. Case in point the PostgreSQL database and its – Ada-based – PL/pgSQL programming language, which allows you to perform significantly more complex operations than would be realistically possible with raw SQL. Case in point the implementation of a Kalman Filter by the folk over at Traconiq, which thus removes the necessity for an external filtering pipeline. Using a Kalman Filter is highly desirable when you’re doing something like vehicle tracking using both dead-reckoning and GPS coordinates, as it filters out noise that can be the result of e.g. GPS reception issues. As noted in the article, transferring state from one row to the next requires a bit of lateral thinking, but is doable with some creative SQL usage. As PL/pgSQL is very similar to Oracle’s PL/SQL, this same code should work there too without too much porting required. The code for the different implement...

Kei Truck Becomes Tiny RV

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Tent camping lets you explore places on foot you could never reach another way, but sometimes you want to camp with a bit more luxury. [Levi Kelly] decided to see how small you could make an RV . [via Autopian ] While we won’t argue one way or another on his claim to world’s smallest, as that likely depends on your definition of an RV, starting with a kei truck certainly puts you in a more compact format than something built on a bus chassis. With four wheel drive and a small footprint, this could be better for overlanding than the Rivian bed camper we featured recently. The 21 sq. ft. (1.95 m 2 ) camper portion itself is framed in 2 x 2s (38 x 38 mm) to save weight and uses foam board insulation. A working faucet uses a pump to draw drinking water from a 5 gallon (19L) refillable jug and empties into a 7 gallon (26L) grey water tank. A solar panel on the roof charges the battery that drives the pump, ventilation fan, and can also be used to run other devices like a hot plate for c...

Building A Desk Display For Time And Weather Data

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Just about every laptop, desktop, and smartphone in your life can tell you the date, time, and current weather predictions. However, sometimes it’s nice to have simple data displayed on a bespoke device. That’s what inspired [Mario] to create ESPTimeCast.  As you might have guessed by the name, the project is designed around the ESP32 and ESP8266 microcontrollers; either one is up to the task of running the show here. Both come with Wi-Fi connectivity out of the box, which makes it easy for them to hook up to the Internet to query NTP servers for the time and weather data from OpenWeatherMap. The data is then displayed on an LED matrix display, made up of four 8×8 LED modules and driven with the aid of the MAX7219 IC. Configuration is handled over a simple web interface hosted on the device itself. All the parts are wrapped up in a 3D-printed housing that would be very fitting in any home that appreciates the magic of late 60s/early 70s decor. Hackers love building clocks , weat...

Building a Functional Aliens Motion Tracker

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Aliens is the second film from the legendary science-fiction series about, well… aliens. Naturally, it featured some compelling future-tech — such as the M314 Motion Tracker. [RobSmithDev] wanted to recreate the device himself, using modern technology to replicate the functionality as closely as possible. While a lot of cosmetic replicas exist in the world, [Rob] wanted to make the thing work for real. To that end, he grabbed the DreamHAT+ Radar HAT for the Raspberry Pi. It’s a short-range radar module, and thus is useless for equipping your own air force or building surface-to-air weaponry. However, it can detect motion in a range of a few meters or so, using its 60 GHz transmitter and three receivers all baked into the one chip. [Rob] does a great job of explaining how the radar works, and how he integrated it into a viable handheld motion tracker that works very similarly to the one in the movie. It may not exactly keep you safe from alien predators, but it’s always fun to see ...

Mesa Project Adds Code Comprehension Requirement After AI Slop Incident

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Recently [Faith Ekstrand] announced on Mastodon that Mesa was updating its contributor guide. This follows a recent AI slop incident where someone submitted a massive patch to the Mesa project with the claim that this would improve performance ‘by a few percent’. The catch? The entire patch was generated by ChatGPT, with the submitter becoming somewhat irate when the very patient Mesa developers tried to explain that they’d happily look at the issue after the submitter had condensed the purported ‘improvement’ into a bite-sized patch. The entire saga is summarized in a recent video by [Brodie Robertson] which highlights both how incredibly friendly the Mesa developers are, and how the use of ChatGPT and kin has made some people with zero programming skills apparently believe that they can now contribute code to OSS projects. Unsurprisingly, the Mesa developers were unable to disabuse this particular individual from that notion, but the diff to the Mesa contributor guide by [Timur...

Electric Surfboard Gets Thrust Vectoring Upgrade

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The internet has already taught us that an electric surfboard is a great way to get around on the water while looking like an absolute badass. [RCLifeOn] is continuing to push the boat forward in this regard, however, adding thrust vectoring technology to his already-impressive build. If you’re unfamiliar with the world of electric surfboards , the concept is relatively simple. Stick one or more electric ducted fan thrusters on the back, add some speed controllers, and power everything from a chunky bank of lithium-ion batteries. Throw in a wireless hand controller, and you’ve got one heck of a personal watercraft. Traditionally, these craft are steered simply by leaning and twisting as a surfer would with a traditional board. However, more dynamic control is possible if you add a way to aim the thrust coming from the propulsion system. [RCLifeOn] achieved this by adding steerable nozzles behind the ducted fan thrusters, controlled with big hobby servos to handle the forces involved...

Segger’s Awkward USB-C Issue With the J-Link Compact Debugger

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Theoretically USB-C is a pretty nifty connector, but the reality is that it mostly provides many exciting new ways to make your device not work as expected. With the gory details covered by [Alvaro] , the latest to join the party is Segger, with its J-Link BASE Compact MCU debugger displaying the same behavior which we saw back when the Raspberry Pi 4 was released in 2019. Back then so-called e-marked USB-C cables failed to power the SBC, much like how this particular J-Link unit refuses to power up when connected using one of those special USB-C cables. We covered the issue in great detail back then, discussing how the CC1 and CC1 connections need to be wired up correctly with appropriate resistors in order for the USB-C supply – like a host PC – to provide power to the device. As [Alvaro] discovered through some investigation, this unit made basically the same mistake as the RPi 4B SBC before the corrected design. This involves wiring CC1 and CC2 together and as a result seeing t...

FLOSS Weekly Episode 849: Veilid: Be a Brick

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This week Jonathan talks with Brandon and TC about Veilid, the peer-to-peer networking framework that takes inspiration from Tor, and VeilidChat, the encrypted messenger built on top of it. What was the inspiration? How does it work, and what can you do with it? Listen to find out! Veilid.com https://gitlab.com/veilid/veilid https://veilid.gitlab.io/developer-book/index.html Did you know you can watch the live recording of the show right on our YouTube Channel ? Have someone you’d like us to interview? Let us know, or contact the guest and have them contact us! Take a look at the schedule here . Direct Download in DRM-free MP3. If you’d rather read along, here’s the transcript for this week’s episode . Places to follow the FLOSS Weekly Podcast: Spotify RSS Theme music: “Newer Wave” Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License from Blog – Hackaday https://ift.tt/ZPnCmRU