Category: SDRplay

TechMinds: Receiving and Decoding Packets from the GreenCube Cubesat Digipeater

GreenCube is a CubeSat by the Sapienza University of Rome, and it is designed to demonstrate an autonomous biological laboratory for cultivating plants onboard a CubeSat.

While this is an interesting mission in itself, for amateur radio operators there is another interesting facet to the satellite. Unlike most CubeSats which are launched in Low Earth Orbit (LEO), GreenCube was launched higher in Medium Earth Orbit (MEO) which provides a larger radio reception footprint over the earth. The satellite also contains a digital repeater (digipeater) at 435.310 MHz, which allows amateur radio operators to transmit digital radio packets up, and have the satellite repeat the packet back over a wide area footprint on earth. 

Over on his latest video, Matt, from the TechMinds YouTube channel shows us how to receive and decode the packets from the GreenCube digipeater. In his demonstration Matt uses an SDRPlay RSPdx as the receiver, SDR++ as the receiver software, SoundModem as the packet decoder, GreenCube Terminal for displaying the messages, and GPredict for tracking the satellite and compensating for the doppler effect. He also notes that while a directional antenna on a motorized tracker is recommended, he was able to still receive packets with his omnidirectional terrestrial antennas without much issue.

RECEIVING AND DECODING GREENCUBE CUBESAT

Guglielmo FM and DAB Receiver Software Updated to Version 0.5

Thank you to Marco, the programmer of Guglielmo for letting us know that his software has recently been updated to Version 0.5.

Guglielmo is a Linux, Windows (and in this recent update x86 MacOS) based RTL-SDR FM and DAB tuner software that supports SDRs including the RTL-SDR, Airspy, SDRplay, HackRF and LimeSDR. It is designed to be an easy to use program designed for media users, rather than hobbyist technical users.

Regarding the release of Version 0.5, Marco writes:

This release sports full mac (x86 only, sorry) and windows installers, DAB and FM scans and a preset editor.

Guglielmo: Screenshot of the DAB Interface

SDRplay RSP1A Metal Enclosure Upgrade Set Reduced in Price

Over on our store we've just reduced the price of the remaining stock of our RSP1A metal enclosure upgrade set. The price reduction brings it down to US$29.95 including free shipping to most countries.

This is a premium aluminum metal upgrade enclosure for the SDRplay RSP1A. It helps block RF interference and protects the RSP inside the sturdy enclosure. This is most likely to be our last production of this enclosure at least for a long period of time.

The kit includes 1x black aluminum metal enclosure with two labelled side panels, 1x black semi-hardshell carry case, 1x thermal pad to keep the RSP1A cool and mechanically stable inside the enclosure, 1x accessory set including enclosure screws, GND lug bolt set and 3M anti-slip rubber feet.

Please note that the set does NOT include the RSP1A.

The sale will only be available while stocks last. There are less than 50 units available from our international platforms, and less than 130 available at Amazon USA. So get in quick before they are all sold!

RSP1A Metal Case Upgrade
RSP1A Metal Case Upgrade

An OpenWebRX fork with additional built in decoders

Thank you to Stefan for letting us know about a relatively modern OpenWebRX fork by luarvique that comes with additional built in decoders and features, such as SSTV, AIS, CW, RTTY, an MP3 recorder and SSTV image browser.

OpenWebRX is an open source web based SDR receiver program that allows you or others (if you allow them to), to access your SDR over the internet. It is compatible with KiwiSDR, RTL-SDR, Airspy, SDRPlay and many other software defined radio hardware. It was originally developed by Andras Retzler, but since abandoned by him, with a semi-official fork being maintained at openwebrx.de. However, other forks like luarvique can exist that implement a new set of features.

The full set of additions and improvements reads as follows:

This is the package repository for the improved version of the OpenWebRX online SDR. The new and original features available in this version of OpenWebRX:

  • Built-in SSTV decoder with background decoding.
  • Built-in AIS decoder.
  • Built-in CW decoder.
  • Built-in RTTY decoder.
  • Built-in MP3 recorder for received audio.
  • Image browser for received SSTV images.
  • Adjustable noise filtering based on spectral subtraction.
  • Adjustable tuning step.
  • Improved touch screen operation, with panning and zooming.
  • Improved scroll wheel support, with tuning and zooming.
  • Improved tuning in CW mode.
  • Bandpass filter adjustable with scroll wheel.
  • More reliable SDRPlay devices operation.
  • Better map information, with distances.
  • Better APRS map information, with weather.
  • Configurable session timeout, with a policy page.
  • HTTPS protocol support (requires SSL certificate).

The code comes packaged for Ubuntu 22.04 (amd64, arm64) and Debian 11 (amd64 arm64, armhf). There is also a ready to use Pi 4 SD card image available, linked on the GitHub readme. The original forked code can be found at https://github.com/luarvique/openwebrx.

According to discussion over on the OpenWebRX groups.io, the fork also runs on a Pi 3. In the image Neil Howard from the groups.io forum demonstrates an SSTV image he received with an SDRplay clone using the luarvique fork of OpenWebRX.

SSTV Image received by the luarvique fork of OpenWebRX. Credit: Neil Howard
SSTV Image received by the luarvique fork of OpenWebRX. Credit: Neil Howard

Stefan also notes:

The maker of OpenWebRX+ Marek and also the maker of the original version of OpenWebRX Jakob are reachable via a Telegram channel: https://t.me/openwebrx_chat

SDRangel Now Available on Android: Mobile ADS-B, AIS, APT, Digital Voice, POCSAG, APRS, RS41 Radiosonde Decoders

SDRangel is a free open source software defined radio program that is compatible with many SDRs, including RTL-SDRs. SDRAngel is set apart from other programs because of it's huge swath of built in demodulators and decoders.

Thank you to reader Jon for writing in and noting that SDRangel has recently been released for Android as a free Google Play download. This is an amazing development that could open up many doors into portable decoding setups as the Android version supports almost every decoder implemented on the desktop version. Jon writes:

It includes most of the functionality of the desktop version of SDRangel, including:

  • AM, FM, SSB, Broadcast FM and DAB, AIS, ADS-B, Digital Voice (DMR, dPMR, D-Star, FreeDV), Video (DVB-S, DVB-S2, NTSC, PAL), VOR, LoRa, M17, Packet (AX.25), Pager (POCSAG), Radiosonde (RS41), Time signal (MSF, DCF77, TDF and WWVB) modems.
  • RTL SDR, Airspy, Airspy HF, LimeSDR, HackRF and SDRplay support via USB OTG as well as networked SDRs
  • 2D and 3D signal analysis in both time and frequency domain with statistical measurements of SNR, THD, THD+N, SINAD, SFDR and channel power
  • Satellite tracker, star tracker, maps and rotator controller

It should work on Android 6 and up. It’s a straight port of the desktop application, so although it will run on a phone, probably best used on a large tablet with a stylus or mouse.

SDRangel on Android
SDRangel on Android
SDRangel

SDRplay RSPdx Black Friday and Holiday Season Sale Now Active

SDRplay have today announced a sale on their "RSPdx" product which runs from today until December 31st. The new pricing is  £130/€156/$169.95 plus shipping and any applicable taxes. This pricing is available for direct sales from SDRplay, and at any participating resellers. The pricing on SDRplay's direct sales platform before the sale was US$214 plus shipping.

Note that individual resellers may be offering slightly different prices depending on if free shipping is offered. For example Ham Radio Outlet in the USA is offering the RSPdx for $179.95 including free shipping.

The RSPdx is designed for high performance DX reception and SDRplay note that it achieves this with additional filtering, improved intermodulation performance, a DAB notch filter, additional attenuation steps, and high dynamic range enhancements for frequencies under 2 MHz.

At SDRplay, we recognise that times are very tough for a lot of people. In view of the economic pressures that people are facing, we want to lend a helping hand by offering the very popular RSPdx at a special low price for this holiday buying season. After discussions with our dealer network, from Black Friday until the 31st December, we (along with participating dealers) plan to offer the RSPdx at a holiday discounted suggested retail price of £130/€156/$169.95 plus shipping and any applicable taxes. This represents a substantial discount of more than one fifth when compared to the normal retail price.

Starting midnight EST, Thursday November 24th visit https://www.sdrplay.com/purchasehome/  to purchase an RSPdx at the special price or contact your local SDRplay dealer for more details.  Please also note that stocks are limited and this offer will certainly end on the 31st December and prices will revert to normal commercial levels thereafter.

This is a great opportunity to get the RSPdx as a gift for a newcomer or a returning radio enthusiast at a price which won’t be repeated, as our suppliers are already increasing their prices for the new year.

  • Prices shown are prices offered when buying direct from SDRplay. Shipping and taxes are extra.  SDRplay ships from the UK to most countries in the world.  However some countries will require import duty to be paid on top.
  • SDRplay dealers who usually include free shipping will adjust the prices accordingly
  • Check with your local dealer to see if they are participating.
  • Links to both the SDRplay direct purchasing page and our list of authorised resellers can be found here
SDRplay - Special RSPdx Holiday Promotion

Frugal Radio: Experimenting with Rdio-Scanner and Trunk Recorder on P25 LSM

In his latest video Rob from the Frugal Radio YouTube channel has uploaded a video where he experiments with a SDR web interface and smartphone App called "Rdio-scanner". Rdio-scanner is an interface that tries to reproduce the user experience of using a real hardware scanner with an SDR and RF voice decoding/recording software like Trunk Recorder being used in the background. Rob writes:

rdio-scanner creates a customizable web interface from which to control your software defined radio. Using it, you can turn a computer, phone or tablet into something that closely resembles a hardware scanner!

Trunk Recorder is the software that decodes the unencrypted P25 signals and records them to disk. Here is it demonstrated working on a large Simulcast (LSM) site.

rdio-scanner reads the audio files. Through the rdio-scanner interface, you are basically choosing which audio files to play.

Rob runs the rdio-scanner software on his Panasonic Toughbook, noting that the interface looks really great in Tablet mode and works well with the touchscreen. He also notes that his toughbook has a SIM card socket, so a data SIM would enable him to access his P25 monitoring system at home from anywhere. 

SDR experiments with Rdio-scanner, Trunk Recorder, Airspy Mini & Panasonic Toughbook on P25 LSM

SignalsEverywhere: Setting up and using SDR++ Server

On this weeks SignalsEverywhere episode, Sarah demonstrates and shows us how to use the SDR++ Server, which was released as a beta earlier this year. SDR++ Server is similar to software like rtl_tcp, and Spyserver as it allows us to connect to a remote networked SDR like an RTL-SDR. Compared to rtl_tcp and Spyserver however, SDR++ Server has a huge advantage in that it is compatible with almost any SDR, and enables the full range of control options for RTL-SDRs.

In the video Sarah shows us how to activate the SDR++ server module and how to connect to a remote RTL-SDR running the SDR++ server on a Raspberry Pi. She goes on to show how to connect to other SDRs running on the Raspberry Pi as well, such as the SDRplay RSP Duo, LimeSDR, Airspy R2 and Airspy HF+ Discovery. Finally she goes on to show how to set up the server on Windows and a Raspberry Pi.

SDR++ Server | Remote RTL-SDR SDRPlay LimeSDR AirSpy and More! | Raspberry Pi and Windows Setup Tut