Wavelet Lab’s uSDR crowdfunding campaign, for a Lime Micro LMS6002D-powered compact single-sided M.2 software-defined radio board backed by a browser-based software platform, has successfully reached its funding goal — with hardware due to ship in February next year.

“uSDR is an embedded software-defined radio (SDR) board that is optimized for ease of use and collaboration,” its creators claim of the device they have designed. “It incorporates WebUSB technology, which enables full functionality in the Chrome browser – under Linux, Windows, MacOS, and Android – without requiring specific drivers or software.”

Wavelet Labs launched a crowdfunding campaign for the board and its clever quick-start software stack earlier this year, which has now closed — having beaten its $40,000 goal, thus providing the funds required for the first mass production run. That doesn’t mean funding has ceased, however: there are still boards planned for the first production run which haven’t found a home, with prices starting at $359 plus shipping for the uSDR board alone.

Interested parties can learn more, or order one of the boards, on the uSDR Crowd Supply campaign page, while Andrew Back has published a hands-on with the platform over on the Lime Micro website.

The LimeSDR XTRX crowdfunding campaign has also closed this month, having successfully raised nearly $63,000 in pre-orders for the redesigned successor to the discontinued FairWaves XTRX Rev. 5 software-defined radio.

Designed to serve as a drop-in replacement for the discontinued FairWaves XTRX while also offering a range of improvements and integration into the LimeSDR ecosystem, including support in the Lime Suite software stack, the LimeSDR XTRX packs a powerful LMS7002M-powered software defined radio into a mini-PCI Express (mPCIe) form factor.

“With the campaign now having drawn to a close, we’d like to take this opportunity to thank everyone who backed LimeSDR XTRX,” writes Lime Micro’s Andrew Back. “We’ll be providing updates between now and when boards ship at the end of November, so keep a look out as we share details of how to get up and running with LimeSDR XTRX, demos, and manufacturing updates!”

The design of the board, as with all LimeSDR boards, is open source – with Altium project files and their outputs, including the bill of materials (BOM), schematics, and board layout, made available in the LimeSDR XTRX GitHub repository, even before the close of the campaign – and includes numerous refinements and enhancements over the original.

These enhancements have been detailed in the latest campaign update, and include design optimisations, component compatibility changes, and what Andrew describes as “a complete rewrite of the FPGA gateware,” which serves to boost compatibility by ensuring full support in the Lime Suite software stack.

Hardware from the first LimeSDR XTRX production run is expected to ship at the end of November, Lime Micro has confirmed, with pre-order still open on the Crowd Supply campaign page for $799.

Private internet access specialist StormyCloud has updated the design of its ADS-B flight tracking platform, FlightTracker, now based on a Raspberry Pi 4 single-board computer and with integrated environmental monitoring.

“We’ve been on a mission to improve our ADS-B tracking setup, and we can’t wait to show you what we’ve achieved,” the company writes of its journey in using Automatic Dependent Surveillance – Broadcast (ADS-B) signals to provide public aircraft tracking information. “In 2019, we started tracking flights and were excited to dive into aviation tracking. We’ve been tweaking and refining our setup, learning from our blunders, and jumping on every chance to improve it. And now, in 2023, we proudly present FlightTracker 3.2 – a massive upgrade from where we started.

“Less clutter: Tidied up the cables and found clever hiding spots. No more messy tangles! Upgraded to Raspberry Pi 4: Switched from 3B to 4GB model for better performance. No more slowdowns! Removed FlightAware filters: Improved range and reduced noise. Enhanced cooling: Replaced single fan with two high RPM fans for better heat dissipation. Added temperature monitoring: Now we can track interior temperature and humidity.”

Information on the build, including links to all the hardware used, are available in StormyCloud’s Reddit thread and on the StormyCloud website.

Satellite communications provider Astranis has announced what it claims is “the world’s first multi-mission geostationary satellite,” UtilitySat – due to launch into orbit by the end of the year.

“This is a new product – the world’s first multi-mission commercial GEO satellite, capable of conducting multiple fully-operational broadband connectivity missions. And it is just the first of many. We’ll plan to launch many UtilitySats in the years to come,” claims Astranis co-founder and chief executive John Gedmark of what he calls the “Swiss Army Knife of satellites.”

“UtilitySat can provide connectivity on standard Ku, Ka, and Q/V bands, and has the flexibility to dial in exact frequencies using Astranis’s proprietary ultra-wideband software-defined radio. It can also relocate dozens of times around the GEO belt over its lifetime. It does this using our unique on-board dual-propulsion architecture, which includes both a chemical monopropellant system and an electric ion thruster.”

Using an on-board software-defined radio system, the idea behind UtilitySat is that it can be quickly repurposed depending on need – orbiting as a “hot-spare” to quickly replaced a failed satellite, add additional capacity to an existing constellation, or to deliver new coverage during times of natural disaster.

More information on UtilitySat is available on the Astranis website and in the company’s supporting video.

Hackaday has brought our attention to a video by FesZ Electronics in which the humble dipole antenna is subjected to considerable scrutiny – from simulation upwards.

“I want to talk about dipole antennas and look at the exact dimension at which they are resonant,” FesZ explains by way of introduction to the video, which was recorded following feedback on an earlier video discussing the topic, “‘resonance’ being defined as the frequency at which the antenna shows purely resistive behaviours without any reactive components. I will be looking at both the simulation prediction as well as try to build and measure some practical antennas.”

In the video, FesZ beings by simulating dipoles ideal and otherwise using the MMANA antenna simulator, discussing real-world issues which mean practical antennas often diverge from the ideal. FesZ’ experimentation also demonstrates just how much wire diameter affects the resonant frequency of the resulting antenna, as much as or more than the material from which the wire is built. There’s even a look at how insulation on the antenna can affect the resonant frequency.

The full video is available on the FesZ Electronics YouTube channel now.

Daniel Marks, PhD, has designed a low-power QRP radio designed to be built using readily-available off-the-shelf components – to serve as a communications platform following disasters natural or otherwise, and boasting a novel digital mode dubbed SCAMP.

“The RFBitBanger is an off-the-grid QRP radio. It is not just designed to be used off-the-grid, it is designed to be assembled and maintained off-the-grid,” Daniel says of the project’s origins. “Most radios require specialised parts that would be difficult to obtain in an extreme parts shortage or in remote places. This radio is designed to be assembled and maintained using the most common jellybean components that might be in a hobbyist junkpile. It will mainly support low bandwidth/digital modes to make the most of limited power.

“The radio has a novel digital mode called SCAMP, implemented on a ATmega328P (Arduino processor) which performs coherent FSK [Frequency-Shift Keying] demodulation and forward error correction to achieve excellent performance in weak signal conditions. No PC is required for this digital mode; it is implemented all on the Arduino. The mode is designed to be simple to set up to make it easy to initiate a contact.”

Design files and source code for the project have been published to GitHub under the Creative Commons Attribution-ShareAlike 4.0 licence and ZLIB licence respectively.

Wired’s Andy Greenberg has written of the alleged sabotage of Poland’s railway system which has been blamed on a vulnerability in the radio communications system — exploitable with just $30 in hardware.

“On Friday and Saturday, August 25 and 26, more than 20 of Poland’s trains carrying both freight and passengers were brought to a halt across the country through what Polish media and the BBC have described as a ‘cyberattack,'” Andy explains. “But as disruptive as the railway sabotage has been, on closer inspection, the ‘cyberattack’ doesn’t seem to have involved any cyber at all, according to Lukasz Olejnik, a Polish-speaking independent cybersecurity researcher and consultant, and the author of the forthcoming book Philosophy of Cybersecurity.

“In fact,” Andy continues, “the saboteurs appear to have sent simple ‘radio-stop’ commands via radio frequency to the trains they targeted. Because the trains use a radio system that lacks encryption or authentication for those commands, Olejnik says, anyone with as little as $30 of off-the-shelf radio equipment can broadcast the command to a Polish train – sending a series of three acoustic tones at a 150.100 megahertz frequency – and trigger their emergency stop function.”

The full article is available on Wired; the Polish State Railways has not commented on Lukasz’ claims.

Finally, radio amateur Bill “WD9EQD” Hemphill has written a guest post for the SWLing Post covering the creation of a low-cost remote antenna switch, built using off-the-shelf components.

“It would be nice to place [my] antennas remotely from the radio (and computers) and then have some sort of remote switch that would select an antenna and then a single feed line to the radio. It was research time,” Bill writes of his project. “A little research and I came across [a] small board that can switch between two SMA antennas. Now that I had the SMA switch module, a way to actually do the switch remotely was required.

“I found a nice Wi-Fi module on Amazon that looked like it would do the trick. But do I really want to use a phone app to switch antennas? Further investigation discovered a really neat module that uses a car fob type control. Bingo! I could just press a button and switch antennas. Next step was to place a latching relay to take the on/off ground and convert it to on/off positive. Again, another nice board was found, [a relay module.]”

Using these, and a plastic enclosure, Bill was able to put together a remote antenna switcher – then expanded the project with the ability to switch a low-noise amplifier in or out of the circuit on demand. A final twist on the concept resulted in a device for switching one antenna between two radios for testing purposes — an inversion of the original design’s functionality.

The full write-up is available on the SWLing Post now.