Yesterday I successfully received APRS transmissions from the International Space Station on 145.825 MHz using my Yaesu FT-817 connected to my MacBook Pro via a Signalink audio interface and a USB sound adapter.
Radios
Articles and blogs about radio receivers and transmitters. Both commercial off the shelf radios and home made DIY experiments by Alexandru Csete OZ9AEC.
Qtmm soundcard modem for decoding AFSK1200
Last week I started on a new experiment trying to integrate the AFSK1200 demodulator code from multimon into a simple Qt-based graphical application. This experiment had two objectives:
- Test the feasibility of integrating the AFSK1200 demodulator from multimon into other applications.
- Try using the QAudio framework from Qt for audio I/O that should work on both Linux, Windows and Mac OS X.
First on the air tests of gqrx
With both the frequency controller and FFT plot widgets in place gqrx was ready for the first on the air tests. The video below shows the first reception of the AO-27 amateur radio satellite during orbit 92436 and 92437, using the Funcube Dongle receiver that I use for portable space communication.
FFT plot and waterfall for gqrx
Following my success with integrating the frequency control widget from cutesdr into gqrx I have decided to try the same with the FFT plot and waterfall widget. This too seemed to be a single C++ class that might be easy to integrate into my experimental software receiver powered by GNU Radio and Qt GUI.
An awesome frequency control widget
Gqrx / C++ update June 4, 2011: After establishing the basic framework for a GNU Radio receiver written in C++ it was time to start working on the GUI framework. As you may recall the GUI will be written in Qt and I am hoping that it will simplify porting the application to Mac OS X.
GQRX C++ Edition
About a week ago I resumed working on GQRX – an experimental AM/FM/SSB software receiver powered by GNU Radio and using Qt for user interface. This time, however, I am not going to continue working on the Python receiver but create a new receiver from scratch written in C++. It will support Funcube Dongle and USRP/UHD devices.
Simple APT decoder prototype
I have wanted to implement a simple APT decoder for the NOAA weather satellites in GNU Radio for quite some time now, in particular since the USRP equipped with a TVRX or WBX daughterboard and a GNU Radio FM receiver can be an extremely good receiver for this purpose. Today I have spent some time looking at the details of decoding APT and actually ended up with a working prototype implemented using the GNU Radio Companion.
FO-29 satellite reception with Funcube Dongle and Arrow antenna
This is the last satellite reception of a series recorded on Monday, February 28, 2011 using the Funcube Dongle software defined radio receiver and the Arrow II hand-held satellite antenna. The satellite is the good old Fuji FO-29 and the recording was made in JO45KG during orbit 71777.
HO-68 CW beacon with Funcube Dongle and Arrow antenna
This is the seventh satellite reception of a series recorded on Monday, February 28, 2011 using the Funcube Dongle software defined radio receiver and the Arrow II hand-held satellite antenna. The satellite is HO-68 / XW-1 and the recording was made in JO45KG during orbit 5791.
Qthid 3.0 for Windows
The Qt-based Funcube Dongle Controller is now also available as a windows binary package – thanks to Mike Willis G0MJW and David Barber G0OQW who have been trying to build it until we eliminated the two build issues (one of them was my fault 😉