Installation of GNU:

https://wiki.gnuradio.org/index.php/LinuxInstall:

$ apt install gnuradio

Add multicast block to GNU radio:

Voor GNUradio 3.10:

git clone https://github.com/fventuri/gr-rtp.git

cd gr-rtp

mkdir build

cd build

cmake ..

make

sudo make install

GNU radio flowcharts

A flowchart is needed for each band separately. So in total 16 flowcharts.

All flowcharts in the directory: ~/GNUradio4websdr_fifo

The multicast stream is received by the multicast block as floats.

Floats are needed for the noise blanker processing or any other DSP.

The floats are converted using a IShort block with a gain 2^15. This block converts a complex sample to interleaved IQ 16-bit values.

The File Sink block streams the 16-bits IQ data to the fifo pipe using the full path name.

Note:

On 80m and 40m the noise blanker is added using NB_core_3.grc, FFT_overlap_NB_3.grc and IFFT_overlap_NB_3.grc.

FFT_overlap_NB_3.grc and IFFT_overlap_NB_3.grc have to be opened first to generate the python code. Then NB_core_3.grc has to be opened to generate the python code.

Only then the code for 80m and 40m can be generated.

Here you can find the zip file, which contains all core and FIFO GNU files.