HackRF in LXC container

 The key requirement is to run a few commands on the host after plugging it in.

mkdir -p /var/lib/lxc/grid22/rootfs/root/bus/usb

umount /var/lib/lxc/grid22/rootfs/root/bus/usb

mount -o bind /dev/bus/usb /var/lib/lxc/grid22/rootfs/root/bus/usb 

This has to be done every time the gadget is unplugged.  There might be a way to automate it by polling /dev/bus on the host or editing a udev script.

 On the container, you have to run

 ln -s /root/bus /dev/bus 

This stays around when the gadget is unplugged.

The container configuration file /var/lib/lxc/grid22/config might require an extra line

 lxc.cgroup.devices.allow = c 189:* rwm

The X server as always requires

lxc.mount.entry = /tmp/.X11-unix tmp/.X11-unix none bind,optional,create=dir,ro

mkdir -p /var/lib/lxc/grid22/rootfs/tmp/.X11-unix

 

 The mane problem is the container's /dev/ directory is a virtual filesystem not part of /var/lib/lxc/grid22/rootfs/.  Anything in /dev/ has to be created after starting the container.  The only way for the container to see anything in the host /dev is to mount it in the visible part of /rootfs & make a symbolic link in the container /dev

 Hackrf/libusb in particular needs to see /dev/bus/usb in the /dev/ directory

 The easiest spectrum analyzer to get working was 

https://github.com/pavsa/hackrf-spectrum-analyzer/releases

You have to download the .zip file.  That works for Linux.

 apt install openjdk-11-jre

 apt install hackrf

Then run hackrf_sweep_spectrum_analyzer_linux.sh 

Fully utilizing the hackrf for transmitting, demodulating, hearing audio, capturing digital TV would require a full gnuradio installation.

 Spent a while trying to get the spectrum analyzer to work in obsolete ubunt 16 but it seems everything is going to require a container now, with the rapid evolution of the C library, no convenient way to keep Ubunt up to date, & no way to have simultaneous versions of the C library.

 



Some captures of the lion kingdom's truck & camera controllers showed their packetized FSK emissions & hardly any harmonics.   The receiver antenna was 915Mhz though.

 qspectrumanalyzer ran into a lot of python dependencies.  It made lions wonder how hard a minimal spectrum analyzer would be. The mane limitation is no way to control the waterfall time scale.

 

 

 

 

 

 

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