QO-100 Linux Transceiver
June 6, 2021The QO100 transceiver is a fully software-based transceiver for small computer boards with an Adalm Pluto running Linux. Up to now, convenient SDR solutions have been available mainly for Windows users with the SDR console. Users of small Linux boards were limited to solutions that were previously simple or difficult to use.
QO-100 SDR Transceiver for Pluto and Raspberry PI
With this SDR transceiver, especially for QO-100, finally also users of Raspberry PI and Co. are equipped with a comfortable software, which makes the satellite operation easy and clear.
Required components:
- Raspberry PI-4, Odroid C4, Odroid N2 or Rocket-PI-4 have been tested, other and similarly powerful SBCs are also usable, as well as Ubuntu based desktop PCs.
- Adalm-Pluto
- 2.4 GHz power amplifier and satellite antenna with LNB and feed.
Operation
The operation of this SDR transceiver is extremely simple. To observe the entire narrowband transponder and to make QSOs only a few mouse clicks are needed. No keyboard is required for radio operation.
In the upper half of the screen, the entire 500 kHz wide NB transponder is displayed as a spectrum and as a waterfall. By mouse click you can select any frequency. This is then displayed in detail in the lower spectrum/waterfall (zoom function). Here you can see the signals with a resolution of 25Hz and observe the quality and frequency response of a transmission.
Frequency tuning is done with both mouse buttons (for RX and TX) as well as with the mouse wheel in selectable increments.
The software transceiver can be operated directly at the LNB and also after down converters, the corresponding frequencies are freely adjustable. For systems without GPS synchronization, two calibration programs are built in, for the TCXO of the Pluto and for the LNB. A beacon synchronisation can also be switched on, which corrects the drift of the LNB clocks in a range of 2kHz and retriggers the received signal.
For a good SSB modulation an AGC and a voice compressor can be switched on. In transmit mode, the own signal heard back can be muted (mute function). The bandwidth for RX and TX can be selected in different steps. The operation is supplemented by audio diagnostic functions (loops) which allow the adjustment of the QO100 system without having to transmit via QO100. As soon as you are satisfied with the signal quality, you switch to normal operation and are immediately QRV via QO100.
Download and further information
Detailed information about the AMSAT-DL QO100 transceiver can be found in our Wiki in the chapter “Software ” – “QO100 Pluto Transceiver”.
- https://wiki.amsat-dl.org
- https://github.com/dj0abr/QO100_Transceiver
- https://www.dj0abr.de/files/qo100trx_rpi_buster_armhf.img.gz