List of SDRSharp Plugins

There are a number of SDRSharp plugins that extend its functionality. Here is a collection of all the plugins and download links that we know of.

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Decoding Inmarsat STD-C EGC Messages

With an RTL-SDR dongle, a cheap $10 modified GPS antenna or 1-2 LNA’s and a patch, dish or helix antenna you can listen to Inmarsat satellite signals, and decode the STD-C NCS channel which contains information such as search and rescue (SAR) and coast guard messages as well as news, weather and incident reports.

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Listening to TETRA Radio

Use your RTL-SDR in Linux to listen to TETRA, a digital trunked radio communications system that stands for “Terrestrial Trunked Radio”.

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Analyzing GSM with Airprobe/GR-GSM and Wireshark

The RTL-SDR software defined radio can be used to analyze cellular phone GSM signals, using Linux based tools GR-GSM (or Airprobe) and Wireshark.

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Decoding Meteor-M2 Weather Satellite Images in Real-Time

It is now possible to decode the Meteor M2 weather satellite images in real time on Windows using an RTL-SDR and a plugin for SDR#.

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Receiving Meteor-M N2 LRPT Weather Satellite Images

The Meteor-M N2 is a polar orbiting Russian weather satellite. With an RTL-SDR an appropriate antenna, you can receive and decode its image downlink and download LRPT weather satellite images.

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Measuring filter characteristics and antenna VSWR with an RTL-SDR and noise source

By using an RTL-SDR dongle together with a low cost noise source it is possible to measure the response of an RF filter. Also, with an additional piece of hardware called a directional coupler the standing wave ratio (SWR) of antennas can also be measured.

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RTL-SDR for Budget Radio Astronomy

With the right additional hardware, the RTL-SDR software defined radio can be used as a super cheap radio telescope for radio astronomy experiments such as observing the Hydrogen Line and meteor detection.

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POCSAG Pager Decoding

Decode POCSAG pager messages with an RTL-SDR. Even in the modern day pagers are still popular with doctors, some fire and ambulance agencies and various service companies, as they tend to be more reliable and have greater coverage.

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Review: Airspy vs. SDRplay RSP vs. HackRF

When people consider upgrading from the RTL-SDR, there are three mid priced software defined radios that come to most peoples minds: The Airspy, the SDRplay RSP and the HackRF.  These three are all in the price range of $150 to $300 USD. In this post we will review the three units and compare them against each other on various tests.

 

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RTL-SDR for Budget Radio Astronomy

With the right additional hardware, the RTL-SDR software defined radio can be used as a super cheap radio telescope for radio astronomy experiments.

Marcus Leech of Science Radio Laboratories, Inc has released a tutorial document titled “A Budget-Conscious Radio Telescope for 21cm“, (doc version) (pdf here) where he shows

Two slightly-different designs for a simple, small, effective, radio telescope capable of observing the Sun, and the galactic plane in both continuum and spectral modes, easily able to show the hydrogen line in various parts of the galactic plane.

He uses the RTL-SDR as the receiving radio with an LNA (low noise amplifier) and a couple of line amps, a 93cm x 85cm offset satellite dish (potential dish for sale here, and here), and GNU Radio with the simple_ra application. In his results he was able to observe the spectrum of the Galactic Plane, and the Hydrogen Line. Some more information about this project can be found on this Reddit thread.

Here is a link to an interesting gif Marcus made with his RTL-SDR, showing a timelapse of recorded hydrogen emissions over 24 hours. Reddit user patchvonbraun (a.k.a Marcus Leech) writes on this thread an explanation of what is going on in the gif.

Interstellar space is “full” of neutral hydrogen, which occasionally emits at photon at a wavelength of 21cm–1420.4058Mhz.

If you setup a small dish antenna, and point at a fixed declination in the sky, as that part of the sky moves through your beam, you can see the change in spectral signature as different regions, with different doppler velocities move through your beam.

This GIF animation shows 24 hours of those observations packed into a few 10s of seconds.

 Marcus’ setup is shown below.

RTL-SDR Radio Telescope Setup

And here is just one of his many resulting graphs shown in the document showing the Hydrogen line.

RTL-SDR Radio Telescope Hydrogen Line

A similar radio astronomy project has previously been done with the Funcube. More information about that project can be found in this pdf file. In that project they used the Funcube, a 3 meter satellite dish and the Radio Eyes software.

However, in this Reddit post patchvonbraun explains that the Funcube’s much smaller bandwidth is problematic, and so the rtl-sdr may actually be better suited for radio astronomy.

This image is from the Funcube project document.

Funcube Radio Telescope Project

Another related project is the Itty Bitty Telescope (IBT), which does not use SDR, but may be of interest.

You may also be interested in Marcus Leech’s other tutorial where he uses the RTL-SDR to detect forward meteor scatter. (doc here) (pdf here)


If you enjoyed this tutorial you may like our ebook available on Amazon.

The Hobbyist’s Guide to the RTL-SDR: Really Cheap Software Defined radio.

13 comments

  1. kiss marco

    hello guys ,i have a typical helical antenna with 12 turns ,for hydrogen line , and i bought it yesterday from somebod ,he made me this antenna by custom , and i have an rtl sdr r820t 2832u , the first appeared on the market, and i bought even a special coax rg 316 and i mount everything in sight and i started to scan to see if the antenna works ,and it scans nothing to me ,no peak or other thing comes in why is that , and what else do i need to receive on 1420 mhz, please help me?

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