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High-altitude ballooning effort Project Horus, a project launched in 2010 by the Amateur Radio Experimenters Group (AREG) of Adelaide, South Australia, has achieve the milestone of transmitting live digital video from the edge of space – using a Lime Microsystems LMS7002M-powered LimeSDR Mini software-defined radio. “Horus 55 was the culmination…

"Just try it," urges Gerhard Burian, who has been experimenting with FreeDV 2020 in partnership with David Rowe and Steve Sampson. "It is amazingly easy to set up a simple satellite station. Just get a LimeSDR Mini, the free SDR-Console software, a small Chinese preamplifier, and 10W power amplifier."

"An open-source software stack allows the students to learn more effectively," says DreamCatcher's Nick Lai. "It also enables them to verify their understanding of the implementation of the protocol stack as per the 3GPP's standard. It is also an excellent platform for developing and testing new algorithms."

Launched in November 2018, Es'hail-2 - QO-100 - is the world's first geostationary satellite for amateur use, and the LimeSDR community has been making full use of it for everything from stabilisation experiments to live TV broadcasting since it entered into active use.

"Using ODR-mmbTools in combination with a low-cost SDR radio like LimeSDR or its smaller counterpart LimeSDR Mini and a small computer such as the Raspberry Pi," engineer Godfrey Laswai explains, "a DAB+ radio station can reach even the most remote areas."

"I attached a cheap 1W high-frequency (HF) amplifier to the LimeSDR Mini," explains system administrator and amateur radio enthusiast Kiril Miloshev, "and with its help I was able to reach Japan, the US, Iceland, the Canary Islands and lots of Europe countries from my home in eastern Europe."

"I would encourage anyone to give this a try," says Daniel Estévez. "If you already have a LimeSDR or a similar SDR supporting large bandwidths, you already have the most expensive piece of equipment. The rest is standard equipment for satellite TV and it is really inexpensive."

"The open software/hardware helps me to understand and utilise all the features that [the LimeSDR Mini] has," explains Kis. "The development time for the limeSNA was about 8-16 hours thanks to the examples and the open source libraries."

"The most important aspect for amateur use of SDRs is that the driver software and toolchain, and the device’s capabilities, are open-source and well-documented," explains BATC chair Dave Crump. "The LimeSDR wins in that it is generally open source, with all the documentation online."

The creation of Andreas Eversberg, Osmocom-Analog - built out of a sense of nostalgia, he explains - allows vintage analogue cellular hardware to live again, connecting to a LimeSDR or LimeSDR Mini equipped PC-based base station.

"I find the ability to modify and look at the source code to be really valuable," explains Carl Michal of his experiments with the LimeSDR in NMR spectroscopy. "I've learned a lot from tinkering with the LimeSDR that I'm sure I wouldn't have with a proprietary system."

"I plan to implement the spectrogram accelerator on a LimeNET Micro and distribute it via LimeNET Store," says developer Gaspar Karm of his effort to implement a hardware-accelerated spectrogram on the LimeSDR family's field-programmable gate array (FPGA) chip.

What do you get if you combine the Raspberry Pi with the LimeSDR Mini? If you're Sam Machin, Andrew Back, and colleagues, you get 16 rapidly-deployable GSM base stations for use at Electromagnetic Field 2018, a three-day event held in the middle of a field every two years.

A project which has seen an LMS7002M-based LimeSDR software defined radio installed on the International Space Station to map and monitor global radio frequency spectrum usage, MarconISSta is already showing interesting results from its early data.

"The final goal is to have a generic satellite receiver that is easy to configure to a new satellite or protocol," project originator Lucas Teske explains of the Open Satellite Project and its open-source weather satellite software.

Evariste Coujard's experimentation with a UNIX-like "KISS" DVB transmission pipeline formed the basis for a self-contained, battery-powered Raspberry Pi and LimeSDR Mini based DVB transmission system.

A LimeSDR-compatible feature-packed open source cross-platform SDR application for ham radio and general purpose SDR workloads.