Re: [Discuss-gnuradio] Move USRP LO with USRP sink block? (was: Re: question per your 2/10/15 post on Ruby Forum)

[Marcus Müller]

Hi John,
I'm a bit confused; which discussion is this from?
Ruby-Forum is not actually the platform we use, they just "mirror" the GNU mailing list archives (I don't really know why they do that -- we don't have anything to do with them). I'd recommend joining that mailing list personally [1].

Regarding your question:
10kHz is very small. Possibly, the closest possible physical LO frequency is still the one you'd have if you didn't shift. Try increasing 10e3 to something that is out of the band that you want to observe; for example, if you're using a sampling rate of 10e6, try 11e6. The only important thing is that the whole observed band stays within the analog bandwidth of your USRP (B2x0) or the daughterboard used (modular USRPs).

Best regards,
Marcus

[1] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

On 06/04/2015 11:26 PM, John Petrich wrote:

Marcus,

 

I cannot get the DC component to shift using this command in the USRP Source block properties:  uhd.tune_request(3.545e6,10e3)  What am I missing?

 

Thank you in advance,

John Petrich

 

Re: Move USRP LO with USRP sink block?

Marcus Müller (Guest)

on 2015-02-10 20:10

Well, you nearly already are doing this!

just use "uhd.tune_request(...,...)" where you'd set the TX frequency

normally in the USRP sink's properties dialog.