Re: [Discuss-gnuradio] Multi-rtl - making multi-channel receiver out of multiple RTL-SDR dongles

[Marcus D. Leech]

On 06/25/2016 04:25 PM, Piotr Krysik wrote:
> Hi Marcus,
>
> If it is possible to do estimate this frequency offset correctly (better
> than one would expect from normal measurement thanks to some a-priori
> knowledge like ~0.072Hz granularity that as you said might be there) - I
> can live with additional step. What might be possibly harder for me to
> swallow is if the estimated value of frequency offset has some error
> that may be avoided if one patches rtl-sdr driver to include the changes
> mentioned by you before.
>
> Thanks for pointing to Peter's East work - I will try to experiment with it.
>
> Best Regards,
> Piotr Krysik
I agree.  i have a fork of the rtl-sdr driver on github now, which turns 
off dither unconditionally, and also sets the CP loop current to max, just
  as the airspy driver does.  Seems to work just fine.

I'll note than Juha Vierinen was able to estimate the offset in 
software, and that estimate held for many many hours of continuous 
operation.