In this tutorial, I'll show you how to work with SDR receivers in Linux. Manjaro Linux will be used for the work, however, any Arch-based distribution will worked with this manual.
There are several reasons why I chose Manjaro Linux. I used Arch Linux for a long time and I'm just used to working with this distribution, however, this distribution can be difficult to configure for beginners. Therefore, it was decided to find something simple to configure, "working out of the box", so that a user who had not previously encountered Linux could easily figure out what's what. For this reason, Manjaro Linux was chosen. As for the popular Ubuntu Linux distribution, in my opinion, the instructions presented below will be slightly simpler than the existing instructions for a similar configuration for the Ubuntu Linux distribution.
- SDR receiver (I will use RTL-SDR.COM V3);
- Antenna for the range you are interested in (I will use Antenna Mini-Whip (TH));
- Computer with Manjaro Linux installed (Preferably a laptop with battery power, will be less noise when receiving);
- Internet connection (for downloading the required packages);
At this tutorial, I will use Manjaro Linux 17.1.7 with Deepin DE with a pre-installed fish shell and a disabled sudo password. However, you don't need set this shell and turning off the password, all actions are repeated on the newly installed, clean system.
First, open the terminal and perform a complete system upgrade using the command:
sudo pacman -SyuThis command synchronizes the repository databases and updates the system's packages.
The next step is to install the Gqrx package, which is used to work with SDR receivers.
sudo pacman -S gqrx
After completing this step, all necessary dependencies will be automatically downloaded and installed. Also, automatic unloading of the kernel modules interfering with the operation of the receiver in the SDR mode will be performed.
After the above steps, you can start working with your SDR receiver. Now, run Gqrx and setting up its initial configuration.
gqrxAfter executing this command, you will see the basic Gqrx settings window. To work with your SDR receiver in the field "Device" select the value "Realtek RTL2832UHIDIR SN: 00000001" (may be different, depends on the receiver used).
If you need the "Direct sampling" mode, the "Device string" field is given to the following form: "rtl=0,direct_samp=2" (without the quotes). If the mode "Direct sampling" is not needed, leave the "Device string" field in the form: "rtl=0" (without the quotes). The parameter "rtl" shows the id of the used SDR receiver, if you use several receivers, this parameter can have a value different from the one specified in the example.
The value of "Input rate" is set to a value of 2400000;
The value of "Decimation" is set to a value of 16;
The last two parameters can be set in their own way, but the settings shown above allow you to simultaneously display a bandwidth of 150 kHz, which is more convenient for me.
If using SDR receiver RTL-SDR.COM V3, do not try to set the value of the "Input rate" parameter more than 2400000, if this parameter is exceeded, stable operation of the SDR receiver is not guaranteed.
Example of settings for working in the normal mode:
Example of settings for working in "Direct sampling" mode:
In the case of using the upconverter, you need to set the LNB LO parameter to the frequency of the converter oscillator with a minus sign. For example, if you use a converter module from this repository, LNB LO value will be -125.00 MHz. In addition, you will need to disable the "Direct sampling" mode (Device string: rtl=0).
Example of settings for working in conjunction with the HF Upconverter:
After setting all the parameters press the "OK" button and get into the Gqrx program. To start receiving, press the "Play (Start DSP processing)" button in the upper left part of the program.
For a more detailed guide to working with the Gqrx program, you can use the following link: Practical tricks and tips - Gqrx SDR
To find additional software for working with the received signal, you can use the following link: Amateur radio (Software list) - ArchWiki
Insert your receiver into the USB connector of the computer and run the following command (Gqrx and any other programs using the receiver should be closed):
rtl_testThis command will be executed indefinitely, until the user aborts execution. Stop the command about a minute after the start (Ctrl + C). If, as a result of the command, the value of "Samples per million lost (minimum)" is zero, your device is working properly.
For using software selectable Bias Tee you should make following steps (manual from RTL-SDR Blog V.3. Dongles User Guide):
sudo pacman -S cmake
git clone https://github.com/rtlsdrblog/rtl_biast
cd rtl_biast
mkdir build
cd build
cmake ..
make
cd src
./rtl_biast -b 1
Important notice, do not try to make "sudo make install", this command will work fine, but running the package with rtl_biast -b X will not work. This error was not eliminated by the developer at the time of April 2018. However, this can be corrected by the following actions (being in the ~/rtl_biast/build/src directory):
sudo cp rtl_biast /usr/local/bin/rtl_biast If you want to disable Bias Tee mode, use the following command:
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