Historically the use of pybombs to install OP25 has been very helpful since it takes care of building all the needed prerequisite software. This is no longer necessary as of Ubuntu 14.04, which installs the 3.7 version of gnuradio. As a result we have a new install method that takes 95% less time than the old pybombs method, is less error-prone, and requires no more RAM than a base install of Linux. You can run this install in a machine with 1GB of RAM, although 2GB is recommended (this recommendation comes from ubuntu, and is caused by the memory-hog GUI - OP25 by itself currently does not require 2GB to compile, now that a source build of gnuradio is no longer required)...
This recipe has been tested on ubuntu 14.04 only, it is likely NOT to work in either 12.04 or 16.04...
First, use these commands to install the pre-reqs
sudo apt-get update
sudo apt-get build-dep gnuradio
sudo apt-get install gnuradio gnuradio-dev gr-osmosdr librtlsdr-dev libuhd-dev libhackrf-dev libitpp-dev libpcap-dev git
Second, use these commands to build and install OP25: [Note, the mkdir build; cd build; cmake ../; make; sudo make install sequence is a bog-standard form when source-building apps that utilize cmake.]
cd ~
git clone git://op25.osmocom.org/op25.git
cd op25
mkdir build
cd build
cmake ../
make
sudo make install
sudo ldconfig
Finally you may need to use the command
sudo rmmod dvb_usb_rtl28xxu
to remove the DVB kernel module that conflicts with the RTL USB SDR. You may also need to edit the system udev rules for the RTL -both are common issues and you can search for the needed resources if the RTL isn't getting recognized... Once this is all done (no longer a need to source any env commands into the shell) you should be ready to invoke scope.py, which is the principal OP25 GUI app... As a pre-check, you can also run the osmocom_fft application (which should install as part of the pre-reqs) to test basic RTL connectivity and rule out related problems before invoking scope.py...
I would appreciate feedback and especially any trouble reports when using these procedures. If all is OK we'll add this to the wiki...
73
Max