Thank Magnesium For Water-Activated Batteries

October 4, 2022 by Lewin Day 16 Comments

Most of the batteries we use these days, whether rechargeable or not, are generally self-contained affairs. They come in a sealed package, with the anode, cathode, and electrolyte all wrapped up inside a stout plastic or metal casing. All the reactive chemicals stay inside.

However, a certain class of magnesium batteries are manufactured in a dry, unreactive state. To switch these batteries on, all you need to do is add water! Let’s take a look at these useful devices, and explore some of their applications.

Continue reading “Thank Magnesium For Water-Activated Batteries” →

Tracking Weather Balloons With SDR

September 8, 2022 by Al Williams 26 Comments

The advent of cheap software-defined radio hardware means that what would have once been an exotic expensive undertaking can now be relatively cheap. [David] notes that using some pretty simple gear, he could track down weather balloons.

The U.S. National Weather Service sends up a large number of radiosondes attached to balloons twice a day. Their job is to measure conditions at high altitudes up to about 30km. Once the balloon gets too high, the pressure inside bursts the balloon, and a small parachute slows the instrument package’s descent back to Earth. [David] wanted to track these down and return them to the NWS for reuse.

Continue reading “Tracking Weather Balloons With SDR” →

A Tracker For Radio Sondes

December 27, 2020 by Anool Mahidharia 12 Comments

Radiosondes – the telemetry packages carried aloft by sounding balloons for atmospheric weather data measurements – are regularly used by weather bureaus around the world to collect data, and there are quite a number of launches daily. Most of them are in Europe, but they also happen at many locations in North and South America, Japan, and Australia. The balloons burst when they reach a high enough altitude, the radiosonde falls back, and most often there is no effort made to recover them since they are deemed “expendable”. So it’s Finders Keepers, and rich pickings for any hacker who is fortunate enough to grab the fallen radiosondes. For successful recovery, you need to first be able to track those radiosondes, and that’s why leet guy [Robert Stefanowicz aka p1337] built his Weather ballon tracker (sic) project.

The hardware is all off-the-shelf, packaged in a pretty cool 3D printed package designed to make it look like the hand held radio that it is. At its heart is the ESP32 based TTGO T-BEAM V1.0 which has almost everything needed for this project. Add an OLED display, 18650 Li-Po cells, antenna and connectors and you can put it all together in an evening over your favourite beverage.

[DL9RDZ] wrote the software which runs on the T-Beam, available at the RDZ-Sonde repo on Github, that allows hunting these balloons. Setup is straightforward, and you need to fiddle with just a couple of well-explained config parameters. Once connected to your WiFi, config and settings can be accessed via convenient web URL’s and the single user action button on the TTGO offers quick access to different functional modes. At the moment, the software is written to decode signals from the widely used Vaisala RS41, Graw DFM06 and Graw DFM09 radiosondes. This LINK provides details for some of the popular radiosonde models.

Once you’re done building this piece of hunting gear, you’ll need some additional help finding out when and where the launches are taking place. If you’re in Europe, you luck out – there is a live radiosonde tracker map, thanks to the great work done by [Michał Lewiński – SQ6KXY]. If you live else where and know of similar resources, let us know in the comments. As a side note, Wikipedia tells us there are about 1300 launch sites worldwide and twice a day missions, so there’s quite a number of fallen pieces of hardware lying around just waiting to be picked up. At the very least, each will have a GPS module and temperature and humidity sensors that you can recover.

So, what do you do with the recovered radiosondes ? Here’s a tip on a “Fallen Radiosonde reborn as active L-band antenna“. And If you’d like to get the skinny on radiosondes, check out “Radiosondes: getting data from upstairs”

Thanks for the tip, [Alex aka MD23F3].

Automated Radiosonde Tracking Via Open Source

February 10, 2019 by Lewin Day 3 Comments

Meteorological organisations across the world launch weather balloons on a regular basis as a part of their work in predicting whether or not it will rain on the weekend. Their payloads are called radiosondes, and these balloons deliver both telemetry and location data throughout their flightpath. Hobbyists around the globe have devoted time and effort to tracking and decoding these signals, and now it’s possible to do it all automatically, thanks to Radiosonde Auto RX.

The basis of the project is the RTL-SDR, everyone’s favourite low-cost software defined radio receiver. In this case, software is used to first hunt for potential radiosonde signals, before then decoding them and uploading the results to a variety of online services. Some of these are designed for simple tracking, while others are designed for live chase and recovery operations. Currently, the software only covers 3 varieties of radiosonde, but the team are eager to expand the project and have requested donations of other radiosondes for research purposes.

The team recently conducted a talk at linux.conf.au regarding the project, which goes into detail as to the decoding and tracking of the radiosonde data. If you’re eager to try it out, download the software, fetch your TV dongle and get cracking. You might also consider tracking cubesats while you’re at it. Video after the break.

via [crazyoperator], thanks to Slds Ernesto for the tip!

Continue reading “Automated Radiosonde Tracking Via Open Source” →

Fallen Radiosonde Reborn As Active L-band Antenna

January 5, 2018 by Dan Maloney 14 Comments

If your hobby is chasing radiosondes across vast stretches of open country, and if you get good enough at it, you’ll eventually end up with a collection of the telemetry packages that once went up on weather balloons to record the conditions aloft. Once you’ve torn one or two down though, the novelty must wear off, which is where this radiosonde conversion to an active L-band antenna comes from.

As it happens, we recently discussed the details of radiosondes, so if you need a primer on these devices, check that out. But as Australian ham [Mark (VK5QI)] explains, radiosondes are a suite of weather instruments crammed into a lightweight package with a GPS receiver and a small transmitter. Lofted beneath a weather balloon into the stratosphere, a radiosonde transmits a wealth of data back to the ground before returning on a parachute after the balloon bursts. [Mark] had his eyes on the nice quadrifilar helical antenna used by the Vaisla R92 radiosonde’s GPS receiver, with the aim of repurposing them. He had a lot of components to remove while still retaining the low-noise amplifier (LNA), but in the end managed to get a working antenna with 40 dB gain in the L-band, and with the help of an RTL-SDR dongle he picked up solid signals from Iridium satellites.

Want to score your own radiosonde to play with? First, you have to know how to listen in so you can find them. Or, you know – there’s always eBay.

[via RTL-SDR.com]

Radiosondes: Getting Data From Upstairs

December 8, 2017 by Dan Maloney 41 Comments

Ever since I first learned about radiosondes as a kid, I’ve been fascinated by them. To my young mind, the idea that weather bureaus around the world would routinely loft instrument-laden packages high into the atmosphere to measure temperature, pressure, and winds aloft seemed extravagant. And the idea that this telemetry package, having traveled halfway or more to space, could crash land in a field near my house so that I could recover it and take it apart, was an intoxicating thought.

I’ve spent a lot of time in the woods over the intervening years, but I’ve never seen a radiosonde in the wild. The closest I ever came was finding a balloon with a note saying it had been released by a bunch of schoolkids in Indiana. I was in Connecticut at the time, so that was pretty cool, but those shortsighted kids hadn’t put any electronics on their balloon, and they kind of left me hanging. So here’s a look at what radiosondes are, how they work, and what you can do to increase your chances of finding one.

Continue reading “Radiosondes: Getting Data From Upstairs” →

Listening In On Weather Balloons With RTL SDR

January 12, 2013 by Brian Benchoff 34 Comments

sonde

Every day, twice a day, over 800 weather balloons are launched around the world at exactly the same time. The data transmitted from these radiosondes is received by government agencies and shared with climatologists and meteorologist to develop climate models and predect the weather. Near [Carl]’s native Auckland, a weather balloon is launched twice a day, and since they transmit at 403 MHz, he decided to use a USB TV tuner to receive data directly from an atmospheric probe.

The hardware portion of this project consisted of building a high gain antenna designed for 162 MHz. Even though the radiosonde transmits at 403 MHz, [Carl] was easily able to receive on his out-of-band antenna.

For the software, [Carl] used SDRSharp and SondeMonitor, allowing him to convert the coded transmissions from a weather balloon into pressure, temperature, humidity, and GPS data.