All SDRs supported by gr-osmosdr and which can tune to the DAB frequencies can be used with grdab. It has
been verified to work with RTL-SDR, HackRF and USRP B200. grdab can receive both DAB and DAB+ audio.
Calibration:
When connecting a new radio, run:
grdab adjust
This will bring up a GUI where you will see the frequency spectrum and the constellation diagram.
1. Drag the channel selector to a valid DAB/DAB+ frequency in your area.
2. Adjust the gain sliders such that frequency spectrum looks good. It should be an almost square
looking wide signal.
3. Adjust the ppm slider until the constellation diagram consists of 4 quite confined dots.
4. Then click 'save configuration'
5. Your SDR is now calibrated and can be used to receive DAB/DAB+ audio.
The calibration data is stored in the file ~/.grdab/adjustment.yaml. Whenever connecting a new SDR, you
will have to repeat the adjustment procedure above.
Checkavailablechannels:
To see what channels are available on a chosen frequency, run:
grdab info -f <frequency_in_mhz>
ListentoDAB/DAB+:
When you find a channel, you can start receiving audio with:
grdab receive -f 227.360 --bit_rate 80 --address 204 --subch_size 60 --protect_level 2 --audiorate 48000
where you replace the different options with the output from 'grdab info' for the desired channel. You
might have to experiment with a few different values for '--audiorate' (such as 44100 or 48000). Note
that DAB+ is default. To receive classic DAB, add '--classic' an argument.
Ncursesapp:
If you create a file called ~/.grdab/channels.yaml, and list all the channels in your area, you can
afterward use the grdab ncurses application:
grdab curses
It allows you to select a channel and listen to it. See /usr/share/doc/gr-dab/examples/channels.yaml for
an example of a channels.yaml file
ZMQsource:
To allow starting and stopping grdab without having to reinitialize the Software Defined Radio, you can
start apps/sdr-zmq-daemon in the background. If you then start grdab with `grdab-z`, it will start much
faster.