Re: [Discuss-gnuradio] Need help identifying jammer signal

[Patrik Tast]

Well done!

Patrik

On Tue, 2013-12-17 at 17:40 -0500, Juha Vierinen wrote:
> Last Friday we managed to finally track this thing down. It was a
> broken FSK telemetry system on an FM radio tower. It was about 30 km
> Southwest of our radar.
> 
> 
> I did a small write up about this:
> http://kaira.sgo.fi/2013/12/perfect-incoherent-scatter-radar-jammer.html
> 
> 
> 
> Thanks for all the help. 
> 
> 
> juha
> 
> 
> On Wed, Dec 11, 2013 at 4:34 PM, Johnathan Corgan
> <address@hidden> wrote:
>         On 12/10/2013 02:00 PM, Miki Lustig - KK6GEO wrote:
>         
>         > These look like 2pi jumps -- which is the an artifact if the
>         > unwrapping is not working well.
>         
>         
>         Sure, I see what you mean.
>         
>         Backing up and just plotting the unwrapped phase, you can see
>         in the
>         first image that overall it is increasing at one rate, then
>         shifts to a
>         lower rate about 1.5 seconds into the file.
>         
>         The finer structure is much more interesting.  The second
>         image shows
>         the phase making fast jumps every 500 samples (10 ms), with
>         periods of
>         oscillation in between.  The detail on this is in image 3.
>         
>         I still have no idea what this is, but it sort of looks like
>         an
>         oscillator that is disciplined at 100 Hz.
>         
>         --
>         Johnathan Corgan, Corgan Labs
>         SDR Training and Development Services
>         http://corganlabs.com
>         
> 
> 
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