Re: [Discuss-gnuradio] WBX power level

[Eric Blossom]

> >>>>Please try the following command with non-UHD for comparison:
> >>>>
> >>>>usrp_siggen_gui.py -x 250k -i 64 --tx-gain=25 -A 1.0  -f 1.3G
> >>>>
> >>>>You should see about 50mW (17dBm) at 1.30025GHz
> >>>>
> >>>>If you change the final argument to 100M you should see around
> >>>>80-100mW (19-20dBm) in the tone at 100.25MHz
> >>>>
> >>>>If you can confirm those numbers, perhaps we have a constant scalar
> >>>>missing in either your flowgraph or the UHD code someplace.
> >>>>
> >>>>Thanks
> >>>>Jason
> 
> Hi Jason,
> 
> I got the test done this morning (after I re-installed gnuradio 3.2.2 )
> 
> Using
> 
> usrp_siggen_gui.py -x 250k -i 16 --gain=25 -a 1.0  -f 1.3G
> 
> 60mW @   1.3 GHz
> 126mW @ 100 MHz
> 
> Using my code and UHD (my code modified to write  I = 0x7FFF, Q = 0x7FFF)
> 
> 14.4mW @  1.3 GHz
> 33.8 mW @ 100 MHz
> 
> Using my code and UHD ( my code modified to write  I = 0x7FFF, Q = 0x0)
> 
> 14.8mW @  1.3 GHz
> 24.8 mW @ 100 MHz
> 
> I ran the power meter's self calibration routine before taking the 
> measurements
> this time and applied the correct frequency correction.
> 
> Looks like we have a bit missing :-(
> 
> - Charles
> 
> http://www.g4guo.blogspot.com/


Does your code set the transmit gain on the WBX?

Eric