Category: Amateur Radio

SkyRoof: New Ham Satellite Tracking and SDR Receiver Software

Recently VE3NEA has released a new Windows program called "SkyRoof". SkyRoof is both a satellite tracking and SDR receiver program. It supports the RTL-SDR as well as Airspy and SDRplay devices.

The software is designed for tracking and receiving ham radio satellites, and it can provide detailed information about all ham satellites, tracking them in real time, and provide pass prediction. It also shows a skymap and SDR waterfall display. The receiver software supports demodulation of SSB/CW/FM, and it automatically compensates for doppler. It can also interface with antenna rotators that support hamlib.

SkyRoof Satellite Tracking and SDR Receiver Software Screenshot
SkyRoof Satellite Tracking and SDR Receiver Software Screenshot

Over on YouTube Johnson's Techworld has also recently uploaded a video showing him testing out Skyroof, which may be of interest to some.

Brief review of SkyRoof, the latest satellite tracking software!

SDR Television: DATV TX and RX Software for the PlutoSDR

Recently, Simon Brown (G4ELI), best known for being the author of the popular SDR-Console software, has released a new program called "SDR Television (Beta 2)". SDR Television is a program designed for transmitting and receiving Digital Amateur TV (DATV) signals.

At the moment, the software supports DATV on the QO-100 satellite, but in the future, further terrestrial DATV support has been promised. The software is designed to be used with a PlutoSDR (or PlutoSDR clone or spinoff), but also supports Airspy or SDRplay for receive only.

Over on YouTube, Tech Minds has also posted a great video demonstrating the software's setup and use.

SDR TELEVISION V1.0 - Game Changing DATV Software From G4ELI!

Creating an Open Source DMR Transceiver with a LimeSDR Mini

Thank you to Adrian Musceac for writing and sharing his article detailing how he implemented an open-source DMR (Digital Mobile Radio) transceiver modem with his LimeSDR Mini and GNU Radio.

DMR is a digital voice communications protocol often used by commercial business band radios, as well as by amateur radio hobbyists.

Adrian explains:

I wrote an article about the implementation of an open-source DMR transceiver using the LimeSDR-mini, GNU Radio and Codec2, which could be used for SDR experiments.

The DMR modem was designed to work both in repeater and direct (DMO) mode, and supports voice and other basic features of the ETSI TS 102 361-1 standard.

In the article there is discussion about aspects of the TDMA transmission, time synchronization, as well as how David Rowe's Codec2 can be used to replace the default vocoder.

The work builds upon Jonathan Naylor's extensive DMR implementation which a large number of amateur radio operators are using as part of MMDVM.

DMR TX Flowgraph
DMR TX Flowgraph
Transmitting DMR with the LimeSDR-mini

TechMinds: Testing out the SDRBerry Software on a Pi 4 with Touchscreen

Over on the TechMinds YouTube channel, Matt has posted a video demonstrating the SDRBerry software, which can be used with many SDR devices, including the RTL-SDR, on a Raspberry Pi with a touchscreen.

The SDRberry software is designed to be used on a touchscreen. As Matt points out, it has an aesthetically pleasing user interface and is compatible with almost any SDR software via the Soapy interface. Combining an SDR with a Pi 4 touchscreen and SDRberry results in an excellent hand-held SDR system.

In the video, Matt demonstrates the features of SDRberry, showing its RX features as well as some of its TX features, such as speech transmission and FT8, via a built-in WSjtx tab. He then shows the optional web interface, which is still in the early stages of development. Finally, he shows how to install the software and dependencies onto a fresh Raspbian image. 

SDRBERRY - This User Interface Is Just GORGEOUS! AND IT USES SOAPY TOO!

Setting up a Dual RX System with an SDR and Ham Radio Rig via an SDRSwitch

There are two common options when using an SDR together with a ham radio rig. You can either create an IF tap within your ham radio and connect the SDR to that, or connect the SDR directly to the antenna via a switch that switches the SDR out when transmitting.

Over on YouTube, Ham Radio DX has uploaded a video discussing the latter option and revealing its advantages. In the video, he mentions results by HB9VQQ that show that connecting an Airspy HF+ directly to an antenna via an SDR switch from SDRSwitch.com results in 60% more spots on WSPR, compared to using an IF tap from an FT450D ham radio rig.

He goes on to explain and demonstrate his setup and the recommended switch that he is using, which is the SDRSwitch by N2EME, available at SDRSwitch.com. He notes that this switch is recommended due to its very low insertion loss and high isolation specifications and compares it against an MFJ switch, which has some rather terrible specifications.

Add a SDR Receiver to ANY Ham Radio Rig!

HOPE XV Conference 2024: Ham Radio for Hackers Talk Video

Back in July 2024 we posted about Dan's (KB6NU) talk at the HOPE (Hackers of Planet Earth) conference about how Ham radio can be for hackers, and how hackers are the future of ham radio. Back then only the slides were available.

The video of the talk has recently been uploaded to YouTube, and is embedded below. The talk emphasizes how ham radio is not only about the traditional thought of making contacts, which is probably in most people's heads, but also about hacking radios, antennas, microcontrollers, satellites, pico balloons, digital communications, GNU Radio, and more. Dan mentions his goal is to promote ham radio to the much younger hacker crowd, where he believes it is underrepresented.

HOPE XV (2024): Ham Radio for Hackers

Building an “HF Helper” for Improving RTL-SDR HF Reception

Over on YouTube Amateur Radio VK3YE has uploaded a video showing his 'HF Helper' project. The HF Helper is a tunable HF filter and attenuator that helps improve HF reception when in the presence of strong overloading signals. VK3YE writes:

Using an RTL-SDR.COM dongle (genuine model V4) and a computer with SDR Sharp you can get quite good reception of HF signals. However reception can sometimes be spoiled by overload from signals on or away from the desired reception frequency. The 'HF Helper' presented here can reduce these problems. And you can use it in conjunction with a QRP transmitter to form a simple transmitting station.

RTL SDR HF Helper improves reception

Also as a bonus, in a related video VK3YE also shows the RTL-SDR Blog V4 being used on SDR Touch on an Android phone for portable HF, VHF and UHF reception.

Hear HF VHF UHF on an Android phone

Ham Radio for Hackers

Over on Hackaday we've seen a post about Dan's (KB6NU) talk at the HOPE (Hackers of Planet Earth) conference about how Ham radio can be for hackers, and how hackers are the future of ham radio. Hackers in this context mean people who enjoy experimenting with electronics, building stuff, and understanding how things work.

Dan's slides have been uploaded on his blog. The slides emphasize how ham radio is not only about the traditional thought of making contacts which is probably in most people's heads, but also about hacking radios, antennas, microcontrollers, satellites, pico balloons, digital communications, GNU Radio and more. Dan mentions his goal is to promote ham radio to the much younger hacker crowd, where he believes it is underrepresented.

Ham radio for hackers
Ham radio for hackers