Use A TV Tuner Dongle As SDR

Software defined radios are neat rigs. The can be costly however if you have a TV dongle that uses the RTL2832U chipset then you are in luck. For $20 you can have a software defined radio. The one I purchased was from DX.com but any tuner will do. The TV tuners generally do not have the best receive versus the actual SDR dongles but you cant beat the price.

As of this writing you can purchase the one I did via http://dx.com/p/ezcap-eztv665-dvb-t-usb-2-0-hdtv-tuner-receiver-set-1-x-cr2025-158821.

It does take a while to arrive but worth the wait. Use the following instructions below to install a full SDR setup in Linux. For this demonstration I will be using Linux Mint 13, However any recent debian based distribution should do.

Open a console and lets begin

System Preperation

First we will install the needed packages and make a folder for all the builds to reside in:

mkdir SDR cd SDR

Now install all the support packages we need.

sudo apt-get install cmake swig libcppunit-dev python-cheetah doxygen libboost-all-dev python-sphinx libfftw3-dev python-numpy libqwt-dev libusb++-dev libusb-dev libusb-1.0-0-dev libgsl0-dev python-wxgtk2.6 qtcreator libpulse-dev

Build and Install GNU Radio

git clone git://gnuradio.org/gnuradio cd gnuradio mkdir build cd build cmake ../ make sudo make install sudo ldconfig

Build and Install RTL-SDR

cd ../../ git clone git://git.osmocom.org/rtl-sdr.git cd rtl-sdr/ mkdir build cd build cmake ../ make sudo make install sudo ldconfig

After this completes you will have a file called "rtl-sdr.rules", using your favorite text editor copy the files contents and append it to "/etc/udev/rules.d/70-persistent-cd.rules"

Building and Install gr_osmoSDR

cd ../../ git clone git://git.osmocom.org/gr-osmosdr cd gr-osmosdr/ mkdir build cd build/ cmake ../ -Wno-dev make sudo make install sudo ldconfig

Building and Install GQRX

cd ../../ git clone https://github.com/csete/gqrx.git cd gqrx qtcreator ./gqrx.pro

A new window will open (the QT compiler). When it opens click the build menu then the build all option. Note this will take a few minutes give or take depending on your system

Plug in your dongle

cd ../gqrx-build-desktop-Qt_4_8_1_in_PATH__System__Release ./gqrx

GQRX Should now be open. On the first run you will be prompted for a device listing. In the device drop down menu select "ezcap USB 2.0 DVB-T/DAB/FM Dongle", then continue to the main GQRX window.

Select File->Start DSP. You should now be receiving something. I found the easiest way to test was to tune to a FM radio station and be sure to select Wide FM Stero as the Mode Type. You should see a screen similiar to below. Adjust gain and other options to play around with it.

Other options are to install a better antenna or a RF amplifier

Cleaning Up

I suggest moving and renaming the gqrx folder then removing the SDR folder. For my system I did the following

mv gqrx-build-desktop-Qt_4_8_1_in_PATH__System__Release GQRX sudo mv GQRX /usr/bin/ cd .. rm -Rf SDR

Now to create a menu so we dont have to launch the console every time we want to start GQRX.

From a console run "sudo gedit /usr/share/applications/gqrx.desktop" ...and place the following in the file, save then close the text editor

[Desktop Entry] Name=GQRX Comment=Ham Radio SDR Exec=/usr/bin/GQRX/gqrx Icon=terminal Terminal=false Type=Application Categories=Network;HamRadio;Education;Astronomy;Science;

You should now have the GQRX program listed in your start menu