Re: [Discuss-gnuradio] Max Output Power from the LFTX daughterboard

[Marcus D. Leech]

On 01/06/2015 08:43 AM, khalid.el-darymli wrote:
> Hi,
>
> What is the maximum output power from the LFTX daughterboard when used 
> with the USRP N200?
>
> According to this datasheet [1], the N200 with the WBX daughterbaord 
> provide an output power of 15 dBm. However, when using the LFTX 
> daughterboard, I am getting a much less output power.
> [1] 
> http://www.ettus.com/content/files/07495_Ettus_N200-210_DS_Flyer_HR.pdf
>
> In GNU Radio with the USRP N200, we use a sinusoid with a frequency of 
> 150 kHz and an amplitude of 0.98, fed into the LFTX daughterboard for 
> a center frequency of 5 MHz. When the output of LFTX is plugged into a 
> scope terminated with a 50-ohm terminator, the scope reads 24.8 mV 
> (peak-to-peak). This is around -28.13 dBm.
>
> Is this the max power one can get out of the LFTX daughterboard?
>
>
> Thanks.
>
> Best regards,
> Khalid
Probably somewhere in the neighborhood of +7dBm, maybe a little more.

The LF/BASIC series have *no* gain in either path, so you're just looked 
at buffered ADC ouput.



--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org