gqrx and tuning

[orcinus]

I've managed to get gqrx (http://gqrx.dk/) to work with bladeRF (not much to it, pretty much works out of the box, once you have gnuradio and osmosdr working), but there's something off...

It looks to me like sometimes tuning stops working, despite the debug messages reading out correct frequencies.

I flip 10 MHz up or down and end up seeing/hearing the exact same spectrum over and over again until i change the frequency by perhaps 100ish Mhz or so. Then it works as expected, but then seems to "lock up" like that again. The way i know it's not just some LO spur i'm seeing is because i've tuned into someone's data bursts (railway sensors, i believe).

The odd part is that if i tune by clicking on the left and right edge of the panadapter, it works as expected (the bursts "move" across the panadapter, or, rather, i can confirm i'm tuning through the spectrum).

Any ideas on what might be causing this?

[bpadalino]

What is your sample rate? And what is your filter bandwidth? If you have a default of 28MHz of bandwidth, but you're sampling at 2MHz, you'll end up getting a lot of aliasing going on which may cause the 'repeated' spectrum - but that's just a guess.

[orcinus]

Sample rate was 1 MHz.
Entirely possible it was aliasing, yeah.

I assumed osmosdr changes the max filter bandwidth to match the sample rate.