On 09/28/2012 04:34 PM, LD Zhang wrote: > I looked and ran the attached GRC file. It does work. I have a question on > whether the slider gain is applied before or after the ADC? >
The set_gain call applies to all gain elements on the RF frontend and in the ADC. In this case, when using LFRX + N210, set_gain only adjusts 6dB of digital gain in the ADC itself. -josh > LD > > On Fri, Sep 28, 2012 at 3:28 PM, Josh Blum <j...@ettus.com> wrote: > >> >> >> On 09/27/2012 02:42 PM, LD Zhang wrote: >>> Yes. I can understand the LFRX does not have any adjustable gain. But >> what >>> comes out of the USRP source should be samples already digitized. Surely >>> there is gain to be adjusted before the ADC. According what I see, it is >>> from 0 to 6dB (in voltage?). I don't see how this can be inserted into >> the >>> USRP source block. >>> >> >> You are correct. The N210 has a 6db digital gain. Attached is a GRC >> flowgraph that loopsback TX and RX with Basic daguhterboards. You can >> see the digital gain slider in action. >> >> The gain parameter in the GRC block is a amalgamation of ADC and RF >> frontend gain elements. The API also allows for individual control, but >> this level of control is not available in the GRC gain parameter. >> >> > _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
