Le logiciel de réception SDR Console de G4ELI
The SDR Console software
To use the signals from an SDR stick, we require “processing” software that will allow us to display the received spectrum as well as demodulate the signals. There are several software programs that allow this. What differentiates them, among other things, is the list of supported devices.
For my part, and especially for the reception of the Qatar Oscar 100 satellite, I have chosen to use the “SDR Console” software published by Simon, G4ELI (HB9DRV). It is available in 32 and 64-bit Windows platforms.
SDR hardware supported by SDR Console
The SDR Console software to this day, can manage nineteen hardware products. You can find the complete list on the author’s website on his Supported Radio page.
Install the SDR Console software
Download the latest version from the website SDR-Radio.com (version 3.0.7 or later) and start installing the software.
Install your SDR device
At the first launch, the software offers you to search for your SDR devices, which must be connected to your computer.
On the Radio Definitions window, click Search to add your device that you have connected to the computer. Here I am looking for the RTL stick.
The software confirms that it has found the hardware. I then click on Add.
The dongle is then added to my “Radios“. Don’t forget to click on the “Save” button.
Beforehand, we will ensure that frequencies above 9999 MHz can be displayed without any problems by the software:
- Click on the View banner then in General on Options
- In the options window, check ‘Show frequency and RX details’ with range = 99.9 GHz, from the Spectrum submenu.
In order to have a direct reading of the satellite frequency (10,489 MHz instead of 749 MHz) after the frequency conversion performed by the LNB, we will indicate to the SDR Console software the frequency of 9750 MHz, which is the conversion frequency of the LNB oscillator.
In the “Radios” hardware definition window, click on the Edit button positioned after the “Converter selection” line.
We will now enter the conversion frequency as 009750.000.000.000 and check Down-converter.
Don’t forget to click on the Save button to save your entry. Here, I entered several frequencies, close to 9 750MHz. The reason is explained below.
After connecting the cable to your T-bias and dish to your SDR receiver, we will start receiving with SDR Console. Select the radio, as well as the frequency of the ‘Converter‘. Click on ‘Start‘.
The reception stabilization option
Since version 3.0.7, the SDR Console software has included a very practical reception stabilization feature. Indeed, the LNB PLL drifts slightly depending on the temperature evolution. Simon G4ELI has developed a software system for controlling the reception window by referring to the modulated BPSK beacon located at the end-of-band of the transponder. The beacon frequency is known and fixed at 10,489,800 MHz.
We will immediately start the SDR Console option which allows the frequency stabilization: In the “View” tab, click on Select of the “More options…” button.
Check the line “Geostationary Beacon” and confirm with OK.
Restart SDR Console.
The feedback window to the BPSK beacon of QO-100
Return to the View tab and now click on the ‘Geostationary Beacon‘ button
At the bottom of the screen is the window “Geostationary Satellite Beacon“.
- Start the waterfall of the Geostationary Satellite Beacon screen, by clicking on the first Start button (the circle)
You should see the upper band beacon modulated in BPSK. If, as in the above capture, you do not see this QO-100 beacon, this means that your LNB has a frequency difference too high for display the beacon in the 10489700 – 10489900 range proposed by SDR Console. To display the BPSK beacon, you will then need to add different conversion frequencies (reduced or increased) to the list of Down Converters, as presented above in the text.
2. On the following picture, and in my case, by selecting a Down converter frequency of 9 749 900, the BPSK beacon appears well now in the window. Click with the mouse on the beacon itself, so that the two white lines at the top and bottom of the window are aligned with the beacon. You then read live the delta of frequencies measured by SDR Console, the delta is the difference between the actual frequency and the expected frequency of the beacon. Here on this capture, it is 13,929 kHz. Considering the conversion currently in place (9749900), the delta is actually 113,929 kHz.
3. To start the frequency correction, click on the second Enable button on the side band. The button is active (highlighted). The entire spectrum is then automatically adjusted by SDR Console to place the beacon at its fixed frequency of 10 489 800 kHz, whatever the real drift that the entire spectrum is undergoing due to the drift of the LNB.
When SDR Console is launched in the future, you will no longer have to perform steps 1 and 2, but only step 3 to select the BPSK beacon and launch the locking feature (click on Enable)