[Discuss-gnuradio] USRP spike

[naveen nischal]

> Hi All,
>
> We have been using the USRP1 with the WBX card on it to communicate with
> the AO-51 satellite. We are expecting to hear from the satellite using
> an Fm Receiver GRC at 435.300 MHz but don't receive anything as yet, we
> are pretty sure about our antenna setup and the GRC are right. The
> problem though is a spurious spike of about 17db which appears at
> whatever center frequency we tune to in the spectrum. we think that this
> might be the problem as that might be jamming the signal which was
> supposed be about the same db level. The point of notice for us is that
> this spike is always there even without the antenna connected. the fft
> is directly the output of the usrp source in the grc so, we are
> presuming that the problem might be in the usrp motherboard .
> Attached is the screenshots FM receiver spectrum. Did anyone have this
> problem? How can we fix it?.

Thanks,

Naveen

fm_spec.png
Description: PNG image