Kritik sah

Southern California is known for its nearly perfect year-round climate, excellent surf, and extremely high cost of living, but once you get away from the coast things are radically different. Rural California has huge tracts of land run by the Bureau of Land Management (BLM), which is publicly accessible to anyone willing to venture into the deserts. There’s not much in the way of infrastructure out there, but [Ryan] does have a unique way of traveling through it using abandoned railroad lines and this custom rail cart . The frame of this cart is simple enough, it’s little more than 2×3 framing with a plywood deck. Some extra support is added for the motor mount and for the seating location. It uses slightly longer go-kart axles to accommodate the width of the railroad, and a small six horsepower gas engine with a single gear to power the rear axle. There are no brakes other than the riders’ shoes, and while this all seems straightforward enough the real hack here is [Ryan]’s custom ...

There are plenty of reasons to devote oneself to the care of houseplants — after all, a room full of bright, glossy-leaved plants can be a joy to behold, and that’s not even one of the more tangible benefits they bring. But as any green thumb knows, there’s a fine line between a healthy, vibrant plant and one that’s soon to give up the ghost. If your thumb tends less toward green and more toward the brown and crusty side of things, something like [Jon]’s Smart Plant system might be just the thing for you. These low-power plant tags are built around increasingly ubiquitous e-Paper displays, like the kind you might find in a retail shelf price tag system. The current version of [Jon]’s tags uses a Waveshare 2.9″ tricolor display and a PCB with capacitive probes that stick into the plant’s soil. An ESP32-S lives on the top section of the PCB, along with a 1,000 mAh LiPo pack that’s charged off USB-C. The design includes an optional solar panel for keeping the battery topped off, which ...

Modern WiFi-enabled microcontrollers have made it affordable and easy to monitor everything from local weather information to electricity usage with typically no more than a few dollars worth of hardware and a little bit of programming knowledge. Monitoring one’s own utility data can be a little bit more difficult without interfering with the metering equipment, but we have seen some clever ways of doing this over the years. The latest is this water meter monitoring device based on a Raspberry Pi Pico . The clever thing here isn’t so much that it’s based on the tiniest of Raspberry Pis, but how it keeps track of the somewhat obscured water flow information coming from the meter. Using a magnetometer placed close to the meter, the device can sense the magnetic field created as water flows through the meter’s internal sensors. The magnetic field changes in a non-obvious way as water flows through it, so the program has to watch for specific peaks in the magnetic field. Each of these sp...

As Tom quipped on the podcast this week, if you have an idea for a program you’d like to write, all you have to do is look around on GitHub and you’ll find it already coded up for you. (Or StackOverflow, or…) And that’s probably pretty close to true, at least for really trivial bits of code. But it hasn’t always been thus. I was in college in the mid 90s, and we had a lab of networked workstations that the physics majors could use. That’s where I learned Unix, and where I had the idea for the simplest program ever. It took the background screen color, in the days before wallpapers, and slowly random-walked it around in RGB space. This was set to be slow enough that anyone watching it intently wouldn’t notice, but fast enough that others occasionally walking by my terminal would see a different color every time. I assure you, dear reader, this was the very height of wit at the time. With the late 90s came the World Wide Web and the search engine, and the world got a lot smaller. For...

It’s the most basic of functions for a camera, that when you point it at a scene, it produces a photograph of what it sees. [Jasper van Loenen] has created a camera that does just that , but not perhaps in the we might expect. Instead of committing pixels to memory it takes a picture, uses AI to generate a text description of what is in the picture, and then uses another AI to generate an image from that picture. It’s a curiously beautiful artwork as well as an ultimate expression of the current obsession with the technology, and we rather like it. The camera itself is a black box with a simple twin-lens reflex viewfinder. Inside is a Raspberry Pi that takes the photo and sends it through the various AI services, and a Fuji Instax Mini printer. Of particular interest is the connection to the printer which we think may be of interest to quite a few others, he’s reverse engineered the Bluetooth protocols it uses and created Python code allowing easy printing . The images it produces ar...

Before video games, there were pinball machines. Not that they don’t exist today, but a modern pinball machine will likely have microprocessors and other fancy things that traditional pinball machine designers could never dream of. [Eli] had one of these mechanical machines from 1974 as a kid and, later, encountered a more modern machine with a rudimentary microprocessor and other integrated circuits onboard. One thing this enabled is the ability to remember high scores. But you have to physically look at the machine, and you can only see the top four scores. [Eli] decided to adapt the machine to upload high score data to the Internet , and it is a fun project. [Eli]’s design goals were to make it automatic and robust. That is, if the network is down or the machine loses power, you shouldn’t lose high score data. In addition, he didn’t want to change the appearance or damage the 40-year-old machine. You can see a video of how it all turned out below. The Laser Cue machine is one of ...

[Shelby] at Tech Tangents recently wrapped a project / obsession to obtain an old HP ScanJet 4C, get it running on a PC and put it through its paces. After after nearly five years, three scanners, and untold SCSI cards and drivers later, he finally succeeded . The first big problem was getting a working scanner. These don’t stand up well to shipping, and one arrived with broken mirrors. And when he finally got one that worked, sorting out SCSI controller and driver issues was surprisingly complicated, though ultimately successful. The HP ScanJet 4C was introduced in 1995, and was notable for its scanning quality, its resolution ( 2400 DPI interpolated / 600 DPI optical ), and selling for under $1000. Except for replacement parts concerns, particularly the customized triphosphor fluorescent bulb assembly, it would still be a very competent scanner today. For this reason, [Shelby] will not be using it as his daily use scanner. DIP-packaged three-line CCD Once everything was running...