[Noisebridge-discuss] Using the National Weather Radio to calibrate SDR-dongles?

[Adrian Chadd]

On Tue, 29 Dec 2020 at 15:12, Andreas Hornig
<andreas.hornig at aerospaceresearch.net> wrote:
>
> Hi noisebridge people,
>
> this is a small call to help that addresses people interested in Software Defined Radio (SDR).
>
> during the corona lockdown in Germany and the holiday season, I had enough time to code a small Python tool for calibrating the known RTLSDR dongles, CalibrateSDR [0, MIT license]. For that I use the DAB+ digital radio system[1], but that is only available in parts of the EU and some other selected places, like in the places I live.
> DAB+ is not available in the US but I have been told that the National Weather Radio NWR[2, 3] could be an interesting candidate to do the same frequency calibration and make my programme useful for you also.
>
> I would like to try to add this feature to CalibrateSDR, but for that I need some recordings of the signal.
> so my call to help goes out to all of you with an RTLSDR, some free time [30 minutes] to tune to the frequency band in your area[2], check with a programme (gqrx SDR#) you like if there is an active signal, and then record it for me (in IQ baseband, a minute or so, 2Msamples samplerate, as 8bit wav-file or dat-binary-file).
>
> that help would be really appreciated, because I cannot do that myself for obvious reasons.
> if you want to help, please feel free to answer in this thread, or contact me directly.

Hi!

Those are all FM stations, so there's 24/7 people saying stuff on it.

So if you want to calibrate against them, you "just" need to find the
carrier frequency, which is easiest when they're not talking. :-)




-adrian
(kk6vqk)