Observation 4909768: FUNCUBE-1 (39444)

Regarding Observation 4909768
This seems fairly low-powered to me. Is it significant enough to be a signal, or is it just noise?

It is a faint but valid FUNCUBE-1 signal on the center frequency. You can compare it with other vetted signals here

The two pair of curving lines off the center frequency are signal from something else, most likely a terrestrial source.

Hello satcolintel5,
on many of my observations (in Luxembourg, Europe) I also have the strange lines next to my FUNCUBE observations. Others observe these lines too. They also appear for other satellites. They puzzle me.

They appear as Dopplershifted since they have an inflection point around the middle of the pass. In my opinion, that would be too much of a coincidence. Could they somehow come from the SatNogs system (RTL-SDR or so)?

Cheers, 73. Jan

p.s. I guess the waterfalls are Doppler-corrected. If so, then terrestrial sources should look as they appear (with changing frequency).

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Hi Jan,

Sorry, just seeing this now. Yes, waterfalls reflect the fact that the receiver frequency is constantly adjusted (several times per second) during an observation to account for the satellite’s doppler shift – so it should show up as a straight line on the waterfall.

Other satellites in view at the same time as funcube can certainly display as having a doppler shift due to a different orbital path (coming/going, similar path but behind/behind by 2 minutes).

And then there are the terrestrial sources with their wavy lines.

Post a link to some particular observations you have questions about so we can have a look.

Hello Satcolintel5,

thank you very much for confirming this.

Cheers. Jan

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