Nooelec SDR: Setup

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Summary

We want to get started with the NooElec SDR. At the end of the setup, the SDR will be ready to use and we will be able to see the first incoming radio signals.

Requirements

  • Operating System: Ubuntu 20.04 is used in this Tutorial, but it also works with other Linux distributions


Description

Installation

Run the command lsusb if you have your NESDR SMArt plugged into your Ubuntu computer. This will list all of the USB devices attached to the computer. If things are working as they should be, you will see the NESDR SMArt listed as: RealtekSemiconductor Corp. RTL2838 DVB-T. The DVB-T is the important part, because it means that the operating system has recognized the device and loaded, what it believes to be, the correct driver.

Nooelec picture 1.png

Can also be seen when using command: lsmod | grep dvb, which lists the loaded modules (drivers) and filters them to just show the ones that have the letters dvb in them. You will see they are loaded.

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We need to remove those modules (drivers) and load the appropriate ones using the device as an SDR. We start by “blacklisting” the default drivers. This is done by editing the file/etc/modprobe.d/blacklist-dvb.conf. Add the following line to blacklist this file.

Nooelec picture 3.png

Then reboot and check. You should get nothing when doing the lsmod | grep dvb command.

Nooelec picture 4.png

What that does is disallow the default module (driver) to load. Now we need to tell it to load the driver we want. First, we need to download it onto the computer. sudo apt-get install rtl-sdr .This will have the drivers and utilities related to using a SDR. Now test the SDR if it works at the lowest level, which is tuning on a particular frequency and seeing if we hear anything. We do this by executing rtl_test.

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The first part of the test will test the parameters of the SDR and then it will attempt to tune in to a frequency. It is at this point you want the test to stop printing to the screen. You have the modules and libraries loaded that are needed to run the dongle as a software defined radio. The next step is to use a software, like Gqrx, that has a “waterfall display”, as you will see. With Ubuntu, the easiest way to do that is with Gqrx. It is available in the Ubuntu Software store, and therefore, easy to install.

Nooelec picture 6.png

Add GNU radio to that; I recommend to download it via CLI with: sudo apt-get install gnuradio gqrx-sdr


Receiving Radio Signal

Having the device connected to the PC and the appropriate antenna, open a terminal and launch gqrx with the command: gqrx

Nooelec picture 7.png

Make sure that the Device line shows the FunCube Dongle or the device you are using. Leave the other fields as they are then click OK. The main window of gqrx looks as below, you can listen to radio if you switch mode to WFM (stereo) – for example go to 104.2 MHz for Radio Energy in Vienna.

Nooelec picture 8.png

Used Hardware

  • Nooelec SDR Kit

Courses

  • Wahlfachprojekt 1 (2021)

References