Thank you to Egor for writing in a sharing his work on modifying dump1090 in order to support the HackRF on Windows. dump1090 is software that is often used with RTL-SDR dongles for decoding ADS-B data for aircraft tracking. He writes:
Some time ago I was looking for dump1090 version with HackRF support that could work on Windows. But I have not found such version.
So I forked Malcolm Robb's version of dump1090 that could be built on Windows around 7 years ago. :) I've updated it and have added HackRF support from Ilker Temir's fork.
Now my version is available here https://github.com/esuldin/dump1090. The main difference from the others that it supports HackRF One device on Windows.
In his latest YouTube video Tech Minds explains and demonstrates Remote SDR V2, which is software that allows you to easily remotely access either a PlutoSDR, HackRF or RTL-SDR software defined radio. It is designed to be used with the amateur radio QO-100 satellite, but version 2.0 now include multiple demodulation modes, NBFM/SSB transmission capability, CTCSS and DTMF encoders, modulation compression and a programmable frequency shift for relays.
In his video Tech Minds shows how to install Remote SDR V2 onto an Orange Pi via the SD card image, how to access the web interface, and how to access and use the connected SDR.
Remote SDR V2 with Orange Pi and Transmit Capable
We note that the code is designed to be run on Orange Pi boards, which are low cost single board computers similar to Raspberry Pi's. However over on Twitter @devnulling has indicated that his own fork of the code should run on x86 systems. Aaron @cemaxecuter is also working on including it into a DragonOS release.
The image below demonstrates a typical Remote SDR V2 transceiver setup with two HackRFs.
A full QO-100 Transceiver Setup with Remote SDR V2 and two HackRF's.
Thanks to Rado for submitting his news about the release of his project called "ggwave-fm" which allows transmitting of ggwave encoded messages with an SDR. The idea behind the original ggwave is to allow data transfer between devices using audio tones. This is useful for things like serverless one to many data broadcasts, device pairing, IoT devices and audio QR codes. Many products such as wireless security cameras already uses a similar audio data transfer system for automatically sending WiFi login data from a smartphone to the camera. Rado writes:
Ggwave is an open-source library that allows you to communicate small amounts of data between air-gapped devices using sound. You can find some technical details and a lot of examples on the project page: https://github.com/ggerganov/ggwave.
I thought it'd be cool to somehow extend the range of transmission for ggwave and this is how ggwave-fm was born. It modulates ggwave encoded messages with NBFM, interpolates the signal and produces a complex sampled IQ file which is ready for transmission with an SDR.
In the video shown below Rado demonstrates ggwave-fm working with a HackRF and uses a Baofeng FM radio as the receiver, with the "Waver" mobile app for decoding. He notes that the demo script (demo.sh) used in the video is availalbe in the Git repository.
Thank you to "LikWidChz" for submitting his tutorial on receiving and decoding multiple NRSC5 (HD Radio) channels with the help of GNU Radio, a HackRF and the NRSC5 decoder. He writes:
I wanted a way to utilize GnuRadio for working with HD radio. There are no decoder blocks from within GnuRadio to perform this decoding without an external application. This write up is how I was able to split up some signal and supply NRSC5 what it requires to perform the decode.
My goal was to capture some slice of spectrum and "channelize it" so I can perform multiple HD radio decodes at once.
In this linked zip file we have uploaded his GRC file, and his tutorial PDF, which fully explains each GNU Radio block used, and how to use the NRCS5 decoder along with the flowgraph. He also notes that if anyone wants to get in touch with him he is idling on IRC in #gnuradio and ##rtlsdr on freenode under the nickname "LikWidChz".
Over the course of 2020 Tomaž Šolc from Avian's Blog has been slowly working on an RTL-SDR based vector network analyzer system. The system currently consists of an ERASync Micro signal generator, a custom time multiplexing board, an RF bridge, an RTL-SDR with E4000 tuner and some custom software.
A vector network analyzer allows the measurement of antenna or coax parameters such as SWR, impedance, phase and loss. It can also be used to characterize and tune filters. In his last post Tomaž copmares his RTL-SDR based system with a NanoVNA-H and shows similar results, confirming that the system is working.
Recently he's also swapped out the RTL-SDR for a HackRF which allows him to make measurements up to 6 GHz. Although he notes that the dynamic range quickly degrades after 3.5 GHz presumably due to connector and phase noise issues.
The entire post chain is a good read to see how he ended up designing the system, and we link to each post below for easier reading:
Over on the Reddit /r/SpaceXLounge discussion board user /u/Xerbot has made an interesting post showing how u/derekcz was able to receive the telemetry signals from the latest SpaceX Falcon 9 rocket launch using a HackRF and a 1.2m prime focus dish with homebuilt feed designed for the 2232.5 MHz downlink frequency. Then after demodulating the signal with GNU Radio, /u/Xerbot was able to convert that signal into binary data, and then into plain text strings.
Another user /u/Origin_of_Mind then figured out that these strings are debug messages being sent by the software-defined GPS receiver, which amongst other data contains the GPS coordinates of the second stage. The GPS data indicates that the second stage was tracking over the north of Serbia at an altitude of 219 km and velocity of 7483m/s. /u/derekcz was able to then confirm that he was indeed recording the signal when the satellite would have been crossing Serbia, confirming the received telemetry was correct.
The entire thread is an interesting read, with multiple users dissecting the plaintext and finding out information about the launch. /u/Origin_of_Mind's post in particular explains the meaning of each of the data fields, which includes the system time, the XYZ coordinates in the earth-centered earth-fixed (ECEF) coordinate system, the loss of precision due to unfavorable GPS satellite positions and the number of GPS satellites currently received.
Another user /u/softwaresaur even notes that there was an "radiation_fdir_activation_guard" event. FDIR stands for Fault Detection, Isolation and Recovery (FDIR) and this event was triggered due to 0.06 s mission time discrepancy between the rocket and GPS true time.
Back in March last year we first posted about the release of SATSAGEN, and program by Alberto (IU1KVL) that allowed the PlutoSDR to work as a spectrum analyzer. SATSAGEN has recently been updated to version 0.5, and it now supports the RTL-SDR, HackRF and Simple Spectrum Analyzer hardware as well.
Spectrum analyzer software allows you to monitor spectrum activity over a bandwidth much larger than what your SDR supports. It works by rapidly sweeping over multiple frequencies and stitching the spectrum slices together.
Some highlights of the new features include:
Works with:
ADALM-PLUTO
HackRF One
RTL-SDR Dongles
Simple Spectrum Analyzer series like NWT4000, D6 JTGP-1033, Simple Spectrum Analyzer, and so on.
Video trigger, real-time trigger, and fast-cycle feature
ADALM-PLUTO custom gain table and Extended linearization table for all devices
DragonOS is a ready to use Ubuntu Linux image that comes preinstalled with multiple SDR program. The creator of DragonOS, Aaron, uploads various YouTube tutorials showing how to use some of the preinstalled software. This month one of his tutorials covers how to use a SDRplay RSP1A or a HackRF to receive and decode FT8 with the preinstalled software WSJT-X or JS8Call. Aaron also notes that an RTL-SDR could also be used as the SDR.
In the video he covers how to set up a virtual audio cable sink in Linux for getting audio from GQRX into WSJT-X, setting up rigctld to allow WSJT-X to control GQRX, configuring GQRX, CubicSDR and WSJT-X, and finally downloading and using GridTracker.
