Disable USRP TX-Chain

I want to switch off the TX-chain because of space-problems with my
custom USRP-design. I did this by commenting every occurence of TX_*
in the common_config* file.

Notice: I took the standard-USRP-FPGA-code and deactivated the TX-chain.

After compiling the code with quartus I tested the RBF-file by calling
benchmark_rx.py (which is located in the gnuradio-examples/python/
digital folder) and calling benchmark_tx.py on an other computer with
the standard-usrp-fpga-code.

But even that simple setup doesn’t work, the script is not able to
synchronize the pakets.

On the other hand: When I’m calling usrp_fft.py with my custom RBF-
file, the spectrum looks the same as the spectrum with the standard
RBF-file.