Thank you to Jason for writing in and sharing with his his recently released software "mmng-ui" which is a TUI (text user interface) for Multimon-NG. If you were unaware, Multimon-NG is multipurpose decoder software for the RTL-SDR and other SDRs which is capable of decoding pager protocols like POCSAG and FLEX, as well as other common protocols like EAS, AFSK, FSK9600 DTMF, CW and more.
mmng-ui is a front end for Multimon-NG that allows you to view pager messages in a clean-looking text interface. mmng-ui listens on a chosen UDP port for raw streams from software like SDR++, passes that to Multimon-NG, and then displays the results.
Back in 2018 we first posted about JJ's Lego Pi Radio, which was an all-in-one RTL-SDR + Raspberry Pi based FM and internet radio system enclosed in Lego.
More recently JJ has written in again sharing with us some updates to his Lego Pi project. First, he notes that he has now created a webpage showing all his radio builds, most of which consist of an Arduino Nano + Raspberry Pi and RTL-SDR, with most enclosed in Lego builds.
JJ also wanted to highlight his latest build optimized for DAB reception, made from an old Android TV box, RTL-SDR the welle-cli software, and of course a Lego enclosure.
My latest build, a FM / DAB+ / INTERNET / MP3 radio, was not made with a Raspberry Pi but with an older Android TV box flashed with Armbian + Ubuntu.
This was cheaper and allowed me to recycle some hardware that was gathering dust. Besides the board needs less power and best of all, the whole system fits into internal eMMC storage, so no more messing with fragile micro SD card. The only problem I had was with the onboard audio so had to use an inexpensive USB audio dongle. I also connected an Arduino nano through USB to easily control a small LCD display and some LEDs.
The board's IR port works well under Linux so I can control the radio with any cheap infrared remote. But I also made a web interface for a fun way to drive the radio from a tablet, PC or even smartphone.
Back in May, we posted about the upcoming DeepRad, which is advertised as a modular RTL-SDR system, providing RTL-SDR PCB boards without USB and SMA connectors that are seated into a custom motherboard. A few days ago they released their crowdfunding campaign on Crowd Supply.
The individual DeepRad RTL-SDR units are priced at US$80 each, whereas the 'DeepRad Quad' which includes four units and a motherboard is priced at US$340 with free US shipping and $12 intl. shipping for both products. It appears that the idea behind the modular boards is to allow people designing a custom PCB to easily seat an RTL-SDR on their design.
The DeepRad Quad advertises 'Synchronize TCXO', which implies that the four units can run from the same clock. However, we don't see any noise source, distribution, or switching hardware, and no heat management, so we don't expect it to be useful for coherent projects like the KrakenSDR is.
Thank you to Jacopo (@lego11/IU1QPT) and Robin (@OK2AWO) for writing in and sharing with us his thoughts about how the SDR community as a whole should move on from the use of WXtoIMG, and instead switch to SatDump, which now has full feature parity with WXtoIMG and additional features too. SatDump is available on Windows, MacOS, Linux, and even on Android. An up-to-date guide for receiving APT with SatDump written by @lego11 can be found on his website here.
Historically, WXtoIMG has been the software of choice for the popular hobby of decoding NOAA APT weather satellite images with RTL-SDR and other SDRs. However, the software has unfortunately been abandoned by its authors for several years, and can now only be found on third-party websites which increases the possibility of downloading a virus. Also, a hack involving a proxy, or directly updating via a powershell script is now required to allow WXtoIMG to update its TLE/ Kepler files due to the celestrak.com to celestrak.org domain name change.
Lego11 also notes a whole host of other issues regarding vulnerabilities and bugs with WXtoIMG:
The software is ancient and uses obsolete libraries, such as Visual C++ 2002 with .NET. These libraries are the main concern when it comes to WXtoIMG, as I don't find it particularly likely for someone to find an entry point through the software itself. However, a much more likely scenario is a virus abusing the loaded library in memory when WXtoIMG is running and using it to gain an entry point. There are at least 20 vulnerabilities affecting MSVCR70.dll, and all are well known (such as CVE-2007-0025) which makes it even more concerning. CVE-2008-4255 in particular allows for remote code execution on the user's computer, which is very serious. There are certainly many more vulnerabilities that have been exploited regarding MSVCR70, but due to the obsolescence of this software component they are usually not tracked in a CVE.
In either case, just as nobody would use Windows XP as a daily driver in 2024, nobody should use WXtoIMG as a matter of caution, even if the above mentioned vulnerabilities were not present.
As for the bugs, there are many. Here's a list of the most important ones:
Cannot update TLE without external software, complicating the experience for newcomers and adding extra failure points
Map overlay doesn't work properly most of the times, especially if the user starts to receive the satellite before it is at least at 1° elevation
WXtoIMG will crash if Microsoft Defender starts a memory scan during a pass. This will lose the recording
WXtoIMG uses an outdated Win32 API to access audio. This doesn't always work on Windows 11 and Microsoft has stated that it will be removed soon.
WXtoIMG uses ALSA on Linux. The vast majority of Linux distributions don't support ALSA directly anymore, and WXtoIMG cannot work through an audio server (e.g. Pulseaudio) like all Linux applications are supposed to. Therefore, live recording doesn't work on Linux at all.
WXtoIMG doesn't run on MacOS anymore, as the system will refuse execution due to security problems and missing libraries.
WXtoIMG cannot support wav files from e.g. SDR# or SDR++ without using a third party tool such as NOAA-APT.
If a user moves or copies a recorded WAV file (see above), the map overlay will no longer work.
WXtoIMG is especially sensitive to concurrent CPU usage, which will result in "tears" on the image (as is evident on the images in the guy's tutorial). It cannot handle multitasking well on systems more modern than Windows XP due to changes in how the CPU scheduler works in more modern kernels.
WXtoIMG will lock up and then crash if the user starts it without first having updated TLEs due to missing NOAA-17. This is very serious, as it happens to newcomers all the time. It is one of the top support request emails/messages I receive. It is not possible to fix this crash easily.
WXtoIMG doesn't have updated coefficients for calibration, therefore NOAA-15 will look excessively cold compared to other satellites.
Over on YouTube Baltic Lab has uploaded a video showing how he was able to successfully use an RTL-SDR Blog V4 and the included multipurpose dipole antenna kit to receive images from polar-orbiting NOAA weather satellites.
In the video, Baltic Lab shows how to orient the dipole antenna in a "V-Dipole" shape which optimizes it for receiving from satellites. He also shows how to use a VNA to confirm that the telescopic elements on the dipole are extended to the correct length, noting that he was able to achieve a VSWR of less than 1.2 between the target frequencies of 135 to 138.1 MHz, with a near perfect match at 136.5 MHz.
He then demonstrates receiving the NOAA APT signals with his laptop, and successfully recovering the weather satellite image.
Images From Space: Receiving Weather Images Directly from NOAA Weather Satellites
Over on the YouTube channel "SecPGH" a talk by Grey Fox titled "Introduction to Software Defined Radio For Offensive and Defensive Operations" has been uploaded from the BSidesPGH 2024 conference. BSidesPGH 2024 was a security conference held in Pittsburgh, PA, USA on July 25.
The talks are generally about network security, however, Fox's talk is all about RF security topics and software defined radio. In the talk, he introduces SDR, and devices like the Flipper Zero and demonstrates various basic examples such as receiving FM from a handheld radio and ADS-B.
Next, he goes on to demonstrate security topics such as showing how to capture and analyze signals from a 433 MHz security alarm using an RTL-SDR and Flipper Zero, and how to jam frequencies and replay captured signals. Finally, he demonstrates WiFi cracking with the help of Kali Linux and Flipper Zero with WiFi dev board attached.
BSidesPGH 2024 Track 2 Grey Fox Introduction to Software Defined Radio For Offensive and Def
Over on YouTube "Sam's eXperiments logs" have uploaded a video showing how he was able to succeed when using TEMPESTSDR to eavesdrop on HDMI cables with his SDRplay. TEMPESTSDR software combined with a software defined radio allows a user to eavesdrop on TVs, monitors, and more by wirelessly receiving their unintentional RF emissions and recovering information from those emissions. In many cases it is possible to recover live images of the display, clear enough to read text.
Sam's video explains the challenges he faced with signal strength due to the highly effective shielding of his HDMI cables. To get around this Sam shows how he unshielded his HDMI cables for the test. This is good news for privacy, as it shows how effective shielding can be at stopping these kinds of attacks. He then goes on to show the results he obtained which show text being read from his screen.
I Finally Succeeded: HDMI Signal Eavesdropping with TEMPESTSDR
Over on the Tech Minds YouTube channel, Matt has uploaded a video where he reviews a new book by Elektor titled "Raspberry Pi 5 For Radio Amateurs" (€5 off coupon code "Techminds"). The book is all about projects for the Raspberry Pi 5 that can be done with RTL-SDR Blog V3 and V4 software defined radios.
In the video Matt explores the books contents, showing off the various possible projects. Matt also shows how to get started with the book by installing Raspbian, and the RTL-SDR drivers, and then goes on to show how examples of the various software programs mentioned in the book such as SDR++, flrig, chirp, dump1090, predict, HamClock, rtl_tcp, rtl_433, qsstv, fldigi, Xdx and more.
Raspberry Pi 5 For Radio Amateurs With The RTL-SDR V4
