Thank you to Steve Cox, creator of the Gorizont Linux distribution for letting us know that the latest update is now out, although it is a small update only. Gorizont Linux is a custom distribution based on Xubuntu 20.04 LTS which contains many preinstalled RTL-SDR compatible programs. Steve writes that the following programs have been updated and added:
- gqrx updated to 2.14.4
- Universal Radio Hacker updated to 2.9.2
- markjfine's nrsc5-DUI HD FM decoder included.
Recently we've seen on GitHub the release of NRSC5-DUI, a fork of NRSC5-GUI which was the first fully functional RTL-SDR compatible HD Radio decoder that we posted about back in 2017. HD Radio is a digital broadcast protocol replacement for analogue broadcast FM. It is only used in North America and is easily recognized as the two rectangular blocks on either side of a broadcast FM station signal on a spectrum analyzer/waterfall display.
According to a Reddit post by u/andrewfer000, NRSC5-DUI includes several upgrades from prior forks, including "better audio processing, better channel switcher, more station information, the option to pull album art from Discogs (currently broken due to Discogs anti-bot), better map displays, cleaner code, and optimizations for Python 3.9".
If listening to audio is not your thing, we also wanted to note that HD radio stations operated by iHeatMedia broadcast live traffic and weather radar data within their HD radio signal as well. With NRSC5-DUI this can be easily decoded and plotted on a map.
When listening to radio stations operated by iHeartMedia, you may view live traffic maps and weather radar. The images are typically sent every few minutes and will fill the tab area once received, processed, and loaded. Clicking the Map Viewer button on the toolbar will open a larger window to view the maps at full size. The weather radar information from the last 12 hours will be stored and can be played back by selecting the Animate Radar option. The delay between frames (in seconds) can be adjusted by changing the Animation Speed value. Other stations provide Navteq/HERE navigation information... it's on the TODO 'like to have' list.
Rob from Frugal Radio has recently uploaded the next part his airband monitoring series. This episode covers the topic of monitoring General Aviation communications, which consists of communications with non-military and non-airline aircraft.
In the video Rob discusses what you might hear on general aviation channels, including things like parachuters, news helicopters, air ambulances, police aircraft, aerial surveyors, ultralights, aerobatics, flight training, private and corporate, and sightseeing. He then discusses the various frequencies in use in Canada, North America and the UK.
Thank you to M Khanfar for submitting his latest video that shows us how to use a launcher that he's created called "GUI SDR TCP STREAMER" (which is actually a combination of several freeware Windows programs including Advanced IP Scanner and TCP Streamer) to stream demodulated audio from SDR# to other PCs over a network connection.
TCP Streamer takes the audio from SDR# via VB-Cable, streams it over TCP to the client PC, then plays the audio on the client side speakers. We note that TCP Streamer should also work with any other SDR program that can output audio to VB-Cable.
Last month we released our new L-band active patch antenna for sale, and not too long after we had a review from Frugal Radio praising it. We now have two more YouTube reviews available to share.
The first is from Tech Minds who does a teardown and demonstrates it receiving and decoding the Inmarsat STD-C NCS channel, receiving and decoding GPS and receiving Iridium signals. The second is from Mike Ladd from SDRplay, who tests it with an SDRplay RSP1A software defined radio. He shows that the patch works perfectly with an RSP1A, and demonstrates it receiving and decoding STD-C while mounted on the dash of his vehicle.
L-Band Patch Stock Availability Note: We note that we are already close to selling out of the first batch of these units as they sold much faster than expected! New sales of this patch are currently backordered but we expect to have a few more units from this first batch available by the end of next week. Also the freighter with Amazon USA stock should be arriving any day now, but it could still take a few weeks to get through the port and reach the warehouse due to the current port delays.
The second production batch of this antenna might still be a while away due to the electronic component shortage crisis occurring now, so if you were thinking about picking one up, please order ASAP.
Back in early and mid March we posted about how several amateur radio hobbyists worked together to receive and figure out how to decode text telemetry as well as live video from SpaceX Falcon 9 rockets using low cost antennas and SDRs.
Unfortunately the fun has abruptly come to an end, with listeners discovering that the latest launch is now fully encrypted. Given the fact that the data stream was undiscovered and likely unencrypted for the last decade, it seems reasonable to assume that SpaceX added encryption in response to media publicity from the decoding discovery. There is also speculation that it may be due to NOAA space camera laws which caused livestream censorship back in 2018.
Sadly all signals from #SpaceX #Falcon9 are now encrypted.
— r00t (@r2x0t) April 7, 2021
It was fun while it lasted... pic.twitter.com/6b1u39Yzod
Over on Reddit u/derekcz has posted about the encryption, and has left us with some final still images reminding us of the fun that was had.
We also wanted to note that if you're disappointed because you ran out and bought antennas and gear specifically to receive Falcon 9 video, you could sill make use of the gear to receive GOES weather satellites, or to detect the Hydrogen line in the galactic plane.
Back at the end of 2018 we successfully crowdfunded KerberosSDR on Indiegogo which was our first coherent capable RTL-SDR that consisted of four RTL-SDRs on a common clock, with built in noise source and phase synchronization hardware. KerberosSDR enabled interesting experiments such as radio direction finding and passive radar to be implemented at a much lower cost.
KerberosSDR has taught us many things, and we're now working on the next iteration which will be a significantly refined version known as "KrakenSDR". KrakenSDR will be a five channel common clocked RTL-SDR, with built in noise source and automatic phase synchronization hardware.
KrakenSDR will be crowdfunded on CrowdSupply, and we currently have a pre-launch page active at crowdsupply.com/krakenrf/krakensdr
Please sign up to the CrowdSupply KrakenSDR email list on the CrowdSupply page to be notified once crowdfunding is launched so that you will be sure to catch the early bird pricing discounts. We expect to be able to launch sometime within the next two months.
Unlike KerberosSDR, KrakenSDR has built in switching hardware that when combined with the new software, will automatically achieve sample and phase calibration without needing to manually disconnect the antennas each time the unit is powered up, or each time the frequency is changed. This allows for much easier mobile and remote use scenarios.
The addition of the fifth tuner also allows us to use a five element antenna array, which results in much improved direction finding accuracy and better multipath rejection. USB-C is also now used on both ports for greater port reliability, the PCB has been redesigned for lower noise, software controlled bias tees are present on each port, and it comes in a tough CNC milled enclosure that doubles as a heat sink.
Finally there is a new open source software base which uses the new synchronization hardware to perform auto phase calibration, allows for intermittent signals to be squelched and tracked, enables long term phase synchronization monitoring, and enables new possibilities for future code expansion especially for passive radar which we will be testing in the upcoming months.
Below are three videos demonstrating the KrakenSDR in action. Please subscribe to the KrakenSDR YouTube channel for more upcoming demonstrations.
If you haven't seen them yet, it may also be interesting to watch our old KerberosSDR videos as well in the playlist below.
Some of our previous KerberosSDR posts might also be of interest.
Over on YouTube Rob from Frugal Radio has uploaded a video reviewing our new L-Band Patch antenna which we released for sale late last month. The patch is currently on a release sale for US$44.95 including free standard airmail shipping to most countries. We will be ending the sale this Wednesday at which point the price will go to US$49.95, still with free standard airmail shipping to most countries. The patch can be purchased from our web store at www.rtl-sdr.com/store.
In the video Rob demonstrates the patch receiving Inmarsat signals strongly, and decodes a few AERO signals using JAERO. He shows that the patch works on any RTL-SDR with bias tee capability as well as an Airspy Mini. Lastly he compares the unit against the SDR-Kits patch.
We note that we are also supplying a kit for a giveaway to Frugal Radio subscribers that we will announce in an upcoming video coming out a few days time.
UPDATE: Giveaway information now available in the latest video below.
