Meteor M N2-2 Has Failed but Recovery May be Possible

UPDATE: It has now been confirmed by Roscosmos that the satellite was struck by what is presumed to be a micrometeorite which caused a leak of thermal transfer gas, and hence a sudden orbit change. It seems unlikely that the satellite will begin operations again as the satellite cannot operate it's camera sensors without thermal cooling. Data is being transmit currently on the X-Band, however, it appears to be a stored image only, rather than live images.

On December 18, 2019, an abnormal situation was recorded on the Meteor-M spacecraft No. 2-2 associated with an external impact (presumably a micrometeorite) on its structure. As a result, he changed the parameters of the orbit and switched to a non-oriented flight mode with high angular velocities.

In accordance with the inherent logic of operation, the device stopped fulfilling the target task and automatically switched to energy-saving mode when the on-board systems that were not involved in ensuring its functioning (including all on-board target equipment) are turned off.

After entering into the zone of Russian ground-based controls with the Meteor-M spacecraft No. 2-2, communication was established and work began to restore its operability: damping angular velocities, transferring to the standard orientation, receiving telemetric and target information.

Currently, work is underway with the satellite under the program of the chief designer. Meteor-M No. 2-2 is in an oriented flight; regular control sessions are conducted with it to receive telemetric information and information from target equipment.

Happysat's Notes:

Depressurization caused gas that was inside and used for heat transfer to leak out.

Resulting in some devices onboard overheating, while others did stop working.

Batteries are working under harsh thermal conditions.

Experts analyzing MSU-MR images during the incident to confirm collision.

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On December 18 Meteor M N2-2 suffered a failure that appears to have changed it's orbit. Roscosmos is quiet on the issue, but speculation by R4UAB is that there was a depressurization or on board explosion. However, Happysat who appears to be in contact with Roscosmos insiders has noted that on December 20 the orbit has been stabilized, and that they are working on recovering the operation of the satellite. Currently the LRPT signal and all sensors remain OFF.

Meteor M N2-2 is a Russian weather satellite that was successfully launched into orbit on July 5 2019. Like with the NOAA and Meteor M N2 satellites, it is possible to receive weather satellite images from this satellite with an RTL-SDR (when it is operational).

The older but still operational Meteor M2 satellite has failed several times in it's history too, each time with the satellite entering an unstable tumble. However, each time the satellite was recovered back into full operation after a few days.

The Meteor-M2 Satellite
The Meteor-M N2-2 Satellite

PiSDR Updated to Version 3.0: Now Supports the Airspy HF+

PiSDR is a Raspberry Pi distribution that is pre-loaded with multiple programs for various software defined radios. It currently supports RTL-SDR, LimeSDR, PlutoSDR, Airspy, and as of the most recent update the Airspy HF+. The currently pre-installed software packages include SDR Angel, Soapy Remote, GQRX, GNURadio, LimeUtil, and LimeVNA.

Recently version 3.0 was released, and this new version adds a few new features like Desktop shortcuts, Raspberry Pi 4 support, Airspy HF+ support and documentation.

The latest image can be downloaded from the PiSDR website at https://pisdr.luigifreitas.me. It can be burned to an SD card in the same way that you would with a standard Raspbian installation. This is a great image to start from if you're experimenting with RTL-SDRs on a Raspberry Pi, as it means that you don't need to go through all the steps of installing the drivers and software like GQRX and GNU Radio which can take a long time to install.

PiSDR Running a SDRAngel with a LimeSDR
PiSDR Running a SDRAngel with a LimeSDR

Tech Minds Demonstrates Iridium Live on a Raspberry Pi

Over on YouTube Tech Minds has uploaded a video of him demonstrating Iridium Live plotting Iridium satellite tracks in real time. We just posted about Iridium Live yesterday. It is a new program by microp11, who is also the author of Scytale-C, a useful Inmarsat STD-C decoder. The software works with gr-iridium to visualize Iridium satellite tracks as they pass overhead.

In the video Tech Minds runs the software on a Raspberry Pi with an Airspy. The current video is only a demonstration, but in the near future he promises to upload a full tutorial

IridiumLIVE - Real Time Visualization Of Iridium Satellites - Raspberry Pi

RadioCapture – Software to Capture, Archive and Listen to Trunked Radio From Many Sources Now Open Sourced

Back in April 2019 we posted about Matt Mills' Radiocapture.com website which is a web service that you can feed that automatically captures analogue and digital trunked radio conversations with an RTL-SDR, and allows public users to play back conversations via the web interface. The Radiocapture page which shows what the software is capable of is also active at radiocapture.com/radio

Back in April Matt was fundraising via Patreon and hoping to make development of Radiocapture his day job, but unfortunately he's had to call it quits for now. Since he no longer has time to work on it, Matt has open sourced the RF side of the software. The software description reads:

[Radiocapture-rf] is capable of using multiple networked computers and multiple SDR radios to demodulate the control channel of P25, EDACS, and Motorola trunking systems, as well as some limited support (alpha quality) for scanning for systems, LTR trunking, and "police scanner" style audio capture.

It is designed to effectively scale to an infinite capacity of trunked systems, captured transmission volume, and dongle bandwidth (more dongles = more available bandwidth, more cpus = more channels and more systems). (There is one remaining feature to be implemented to really make this work well, dongle redis autodiscovery (frontend_connect should autodiscover and use available dongles) and splitting the rc_frontend/receiver.py into one process per dongle.

The frontend initializes the SDRs in whatever configured frequency range, and presents a server interface where clients can connect and request a specific channel be created and forward to them. The frontend will then attach a channel, and output to a UDP sink (might be something better now, I forget). On the backend side, a control_demodulator is listening to that sink and doing the actual RF demodulation, which is passed into redis for distribution to other services. The backend is effectively a bunch of microservices that work together to track & record all ongoing transmissions and do some amount of deduplication. This entire setup is designed such that it can be scaled across as many servers/computers as necessary (although there are a few caveats/things I never got around to implementing in how it actually works). Recorded transmissions are decorated with a metadata scheme in their mp3 tags that is designed to be able to be loaded into the Radiocapture.com database. Finally completed mp3s are dropped into an activemq queue for publishing.

Matt notes that the software in it's current state isn't considered as "ready to distribute" as you may need some decent experience with Linux and Python to get it up and running.

RadioCapture logged audio
RadioCapture logged audio

Mike from SDRplay Compares the RSPdx Against Other SDRs on MW/LW

Over on the SWLing post blog we've seen a post contributed by Mike Ladd who works with SDRplay. Mike has been comparing the new SDRplay RSPdx on medium wave and long wave reception against the Elad FDM-S2, Airspy HF+ Discovery and the Perseus. The RSPdx is SDRplay's latest product which sits at the top of their line as their highest performance single tuner receiver.

Each test consists of a video where he runs a comparison between the RSPdx and another receiver. All SDRs are run in SDRuno, the official application for SDRplay receivers. It is left for the listener to determine which SDR sounds better. From a listeners perspective, it appears that the RSPdx performs at least identically to the other SDRs.

Comparing the RSPdx Against other SDRs
Comparing the RSPdx Against other SDRs

IridiumLive – New Software to Plot Iridium Satellites as They Pass Overhead with an RTL-SDR

Over on GitHub, microp11, the author of Scytale-C has released a new browser based program called IridiumLive which allows you to visualize the live positions of Iridium satellites as they pass overhead. Iridium is a satellite constellation that provides services such as global paging, satellite phones, tracking and fleet management services, as well as services for emergency, aircraft, maritime and covert operations too.

The software uses gr-iridium as the data source, which is an RTL-SDR and other SDR compatible Iridium satellite decoder. See this very interesting talk by the gr-iridium authors for more information, and this video by Techminds which shows how to install and run gr-iridium.

Also in order to receive Iridium satellites in the first place, you'll need an appropriate antenna such as our "RTL-SDR Blog Active L-Band 1525 - 1637 Inmarsat to Iridium Patch Antenna Set" which is currently available on our store.

Instructions for installing and running IridiumLive are available on the Git readme. Once installed you can browse to the IridiumLive web page on your local network, and view the tracks of the Iridium satellite fleet as they pass overhead, as well as the locations of Iridium signal activity from the ground.

IridiumLive Screenshot
IridiumLive Screenshot

Radio Analyser: New Program for Plotting DSDPlus Statistics

Thank you to Matthew Cowley for submitting news about his new program called "Radio Analyser". Radio Analyser is a program that imports DSDPlus radio and group files into a postgresql database. The data can then graphed on the web interface allowing you to view talk group and radio statistics. DSDPlus is a program that can be used to listen in to digital P25, DMR and other digital voice protocols with an RTL-SDR or similar SDR.

Matthew writes the following, and some screenshots of the interface and graphs are shown in the slider and the end of the post:

I've been learning Ruby on Rails and as a first project I wrote a project that you host at home which imports the DSDPlus.radios and DSDPlus.groups files and displays their activity in graph form. It will show you total site activity, talk group activity and radio activity.

Reprogramming a €15 USB Audio Dial to work as an SDR VFO Knob

Thank you to Tysonpower (aka Manuel DO5TY) for submitting information about how he's managed to convert a cheap €14.33 USB audio control dial into a VFO tuning knob for use in SDR programs like SDR-Console V3. He writes:

I sometimes miss a VFO Knob while using my SDRs, especially with SSB Signals or CW where you need to adjust the Frequency very fine.

Because of that I got myself an Audio Dial with USB, reverse engineered it somewhat and wrote a new Firmware for the STM32 used in the USB Dial.

It all worked out and it now simulates a mouse wheel with three different scroll speeds. There is also a Mute Function when you long press the Button.

I had a lot of fun during this project, even when it was a lot of time just for a VFO Knob :)

Manuel's blog post goes into deeper detail on how he reverse engineered the knob and how he re-programmed the STM32 microprocessor. He also includes the HEX file if you want to purchase the same unit and reflash it. His video below shows the modified knob in action.

[EN subs] VFO Knopf für SDRs aus einem Lautstärkeregler