Re: [Discuss-gnuradio] USRP source gain problems?

[Eric Blossom]

On Mon, Jul 21, 2008 at 05:59:23PM -0500, Jason Uher wrote:
> I am trying to read samples from the USRP and the only samples I
> receive back are integers between -2 and 2; not the -1500 to 1500 that
> I get when running the samples.
> 
> As far as I can tell there is no difference between my set up and the
> examples, I initialize the subdevice, set the gain choose the antenna,
> and tune the receiver, but I only get the
> very small integer values, whats wrong?
> 
>   ur = usrp.source_c(0,rx_decim_rate)
> 
>   rx_sd = (1,0) #manually choose the correct device
> 
>   #Set up the USRP mux values
>   r_subdev = usrp.selected_subdev(ur, rx_sd)
>   m = usrp.determine_rx_mux_value(ur, rx_sd)
>   ur.set_mux(m)
> 
>   r = r_subdev.gain_range()
>   r_subdev.set_gain((r[0] + r[1])/2)
> 
>   r_subdev.select_rx_antenna( 'RX2')
>   r = ur.tune(r_subdev._which, r_subdev, 24e8)

I don't know if this is a problem, but you're not checking for errors
after any of the calls.

This should be:

  r = ur.tune(0, r_subdev, 24e8)

Eric