Author: Bryan Cockfield

1892 Articles

Going Whole-Hog On A First Satellite Ground Station

October 20, 2026 by No comments

When most radio enthusiasts start trying to pick up signals from satellites, they might put together a quick-and-dirty Yagi antenna and try to catch a repeater as is passes overhead, or they might grab a small unused dish from a satellite TV service and point it up at a weather satellite by hand to try to decode some of the data coming down. But [Cranktown City] had a different approach. He found an eight-foot dish online and built a massive articulating base station out of it as his first exploration into the world of satellites.

The first problem that needs to be solved with a dish of this size is its mounting location. This installation uses a large post and concrete foundation with a custom-fabricated metal base at the bottom. The metal base houses all of the electronics not just for receiving signals from the dish, but also for orienting it properly. That includes a large metal gear driven by a wheelchair motor to control its azimuth and a linear actuator to take care of its elevation. Getting the large dish onto the frame was its own ordeal, complicated by the fact that it’s not uniform in its shape and has to be mounted in a specific orientation.

With everything assembled, the circularly-polarized antenna installed, and the computers up and running, the dish is able to track satellites across the sky and download data from things like GOES weather satellites. [Cranktown City] also built in a system that detects wind and points the dish vertically when it goes above a certain speed. This level of effort is impressive, and absolutely not required to listen in on plenty of sattelite activity out in the sky, but this installation will certainly give [Cranktown City] a lot of mileage and possibly even work for some radio astronomy.

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An RV On A Bike

October 19, 2026 by 25 Comments

Bicycles are the ultimate form of transportation freedom. They’re easy to repair, parts are cheap, and they will travel almost anywhere for free, as long as the rider has enough calories. Their only real downside is dealing with car-dependent societies, but once a year there’s a place in the American desert that eschews all of this and [Attoparsec] decided to take this custom cargo bike modified into an RV out to Burning Man, a place and time that would be perfect for a build like this.

The build started out as a cargo bike, but not many of them have cargo areas long enough to support a sleeping human. To increase this storage capacity, the bed was extended towards the rear. Without moving the axle further back, though, this created a problem with tail-heaviness so two trailer jacks with wheels were added to the back to keep it from occasionally tipping up too far. The sleeping enclosure was built with rigid foam insulation and taped together, in a modified style common to the Burning Man event which helps keep out sun and playa dust. The bicycle recived one last upgrade to the chain to support the extra weight, and a solar-powered refrigerator, and then it was off to the desert.

The bike RV worked well in the end, and even handled a rain storm without the roof leaking. There were some problems with the customized drive train which were solved in the short term by pounding on one of the wheels occasionally with a hammer. [Attoparsec] left the event early for other reasons, though, and might not be back for a while. But vehicles like these are gaining in popularity, presuming there are safe places to ride them. [Paul Elkins] is often making ones like this gas-powered bicycle and trailer camper.

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Meshtastic Sniffer For DragonOS

October 19, 2026 by 1 Comment

Meshtastic has gained a lot of popularity over the last few years thanks to its low barrier of entry. No licenses are needed and the hardware is dirt cheap, at least when compared to a lot of ham radio gear. But while that physical barrier is low, there is a bit of a learning curve. Part of that comes from the fact that there are a lot of channels and modes that people could be communicating on, and unless the user knows that information up front it can be hard to find where the conversations are happening. [cemaxecuter] noticed this problem and built a Meshtastic sniffer into his radio-forward Linux distribution, DragonOS.

The sniffing software is built in C and comes as a complete standalone binary and does not rely on GNU Radio. With DragonOS up and running and the software loaded, it can look at the entire bandwidth that Meshtastic operates on and detect any traffic and decode it (as long as the key is known). [cemaxecuter] is using a HackRF as a software-defined radio for this project, which he notes doesn’t quite have enough bandwidth to cover every Meshtastic operating frequency, but it can get most of them. After firing up his own node, the software quickly detects it and shows its details in the terminal.

Software like this opens up a lot of opportunities for things that would be tedious, difficult, or impossible to do with with a standard Meshtastic node. Besides finding places where conversations are happening more easily, [cemaxecuter] also suggests that it could be used for wardriving and for locating or finding other networks much more easily. For those who still haven’t tried it out, take a look at this 2023 treatise on the protocol and hardware and then dive right in.

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Off-Grid Refrigeration Using Fire And Salt

October 18, 2026 by 29 Comments

Refrigeration has been a challenge for humanity since the start. Ancient civilizations in dry climates like Persia and Egypt could use evaporative cooling on a large scale with specialized architecture, and with easy access to electricity modern civilization can cool down almost anything it wants. But whether in a refrigerator or heat pump, the electricity demands can get out of hand quickly, and heat-driven systems often require dangerous or hard-to-get chemicals. But [Greenhill Forge] has crafted a system that creates effective refrigeration with only fire and salt… and a bit of electricity.

Heat-driven systems are called absorption coolers. In this design, water is used as a refrigerant and forced to a very low pressure so that it can boil at a low temperature. When it boils it absorbs heat from the surrounding environment, and then that water vapor can be moved and condensed where it gives off that heat. The build has a few distinct loops to make all of this happen. The generator loop holds the heat source and a tank of water mixed with road salt. Boiled water travels up a tube to a condenser. A valve here is opened slightly to allow the water to drip into the absorber section, where it is under low pressure and boils rapidly. The vapor is carried away by the third system, which uses a shower of the salt solution to quickly suck up the vapor and move it away from the cooled area.

There is a small amount of electricity needed to run pumps and fans, but to keep this off-grid this requirement is easily met by a small solar panel or battery. The bulk of the energy is from the fire which boils the saltwater solution. [Greenhill Forge] added a number of temperature and pressure sensors to monitor and control the system as well, and in his firsts tests the refrigeration system was able to get to about 5° C with an ambient temperature around 16° C. That’s not quite the temperature needed for a refrigerator, but not bad for only salt and fire. [Greenhill Forge] has a number of other ingenious off-grid builds like this sawdust stove and a magnetic induction water heater.

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Pager Converted To Meshtastic Node

October 14, 2026 by 10 Comments

Text messaging has been around on cellular networks en masse for around three decades now. It’s so common that it’s difficult to remember a time without it. Its two-way quick messaging is incredibly useful, but for even simpler communications there’s a one-way system that predates it. Pagers are able to receive simple messages, but outside of hospitals are rarely used nowadays. Eventually some added in two-way communications like this Motorola T900, but they’re still mostly obsolete. That’s why [zindustries87] converted it to operate on the Meshtastic network instead.

To get this pager working, a lot of reverse engineering was needed. There is essentially no documentation on the chips in these devices, so the screen and keyboard both were reverse-engineered to work with other hardware. In this case, [zindustries87] found space for a Heltec V4 with an ESP32-S3, a popular Meshtastic node with a small form factor. Some programming was needed to get everything communicating together, but from the looks of things it seems to have basic functionality.

[zindustries87] points out that this is a prototype, and didn’t know going in if the keyboard and screen could be brought back to life, or if the other hardware would fit in the case. But with it working on this level, they plan to add a number of other features in and possibly build a drop-in PCB replacement for these devices. They were once fairly popular so there are plenty around, and they’re a good form factor for a dedicated Meshtastic device that doesn’t need a smartphone to work. The only other ways of bringing pagers back to life involve bootstrapping an entire pager network, and Meshtastic is a bit more useful than that now.

Single Button, Handheld Gaming Console

October 14, 2026 by 7 Comments

Those of us who grew up in the 70s and 80s might be familiar with the Atari 2600 console and its now relatively unrecognizable (by modern standards) controller with only a single button and stiff whole-hand joystick. By comparison, the Steam Deck has somewhere around 24 buttons and two joysticks depending on how they are counted. But even the Atari might be providing more user inputs than are really necessary for quality gaming. Take a look at the Dinoboy, a handheld console with only a single button.

Part of what makes this system work is that it’s playing the classic dinosaur jumping game first included in Google Chrome which loads when the browser can’t connect to the Internet, and the user’s single input was the space bar. In this case, the handheld has its single button where the user’s thumb naturally rests. The console itself is in two parts, hinged where the button is placed. When unfolded, the top half reveals a wide screen and the bottom half is held by the hand. The screen supports two color formats, a black and white style and another which replicates the dot matrix display of the original Game Boy.

The small handheld console has another trick up its sleeve too. [Paul], the system’s creator, built it as a way to stop doomscrolling so along with having this quick-deploying game on hand, there’s also an NFC tag hidden near the hinge which, when swiped passed a phone, also turns that phone’s airplane mode on. It’s a double-whammy of removing the gamer from the dark patterns and algorithms dominating the mainstream Internet. And, this isn’t [Paul]’s only dinosaur jumper console either. We recently featured a similar (but much larger) build of his housed in a classic arcade-style cabinet.

Super Mario 64 Comes To The Microsoft Zune

October 9, 2026 by 8 Comments

As a portable media player, Microsoft’s Zune simply couldn’t compete with Apple’s juggernaut iPod — the latter essentially becoming the de facto personal media player until smartphones took over. But in 2026 it might be Microsoft that gets the last laugh, as thanks to [rsheldiii] the Zune can now play Super Mario 64.

The software is based on sm64ex, and notably doesn’t include the ROM file necessary to actually run the game. But presuming a legal dump of a cartridge has been done, building and loading it onto a Zune HD is straightforward enough. From there the player is presented with a controller interface on the device’s touchscreen overlaid with the video output from the game. Some interesting things are happening in the background here as well, like using NVIDIA’s Tegra tools to pre-compile shaders so the 2009-era processor can handle the rest of the gameplay.

Although it didn’t enjoy the mainstream success of the iPod, the Zune was actually a pretty solid device, and even though the last of them rolled off the assembly line back in 2012, there’s still a fairly active userbase for it. Modern improvements have added Bluetooth and solid-state drive upgrades for them have been available almost since they were first released.