Observation 1841284: NEXUS (43937)

Regarding Observation 1841284

Sorry for the newbie question.

I am just trying to test out my first ground station with a rdl-sdr and simple dipole antenna connected to a raspberry pi 3. I was expecting to at least see the tangent-shaped lines in the observation, wasn’t expecting to pick up a signal. If that isn’t there does that highlight a problem?

As compared to this example: https://wiki.satnogs.org/File:Waterfall_20499_2017-10-15T07-17-32.png

I have a cross diopole antenna coming, just wanted to check the setup first.

Without really knowing your station, I would say that that is a “bad” observation and not a “failed” one.

The “tangent” lines come from terrestrial noise “birdies”, so if there is no noise at your station, you won’t see those. Typically, failed observations are only when there is no waterfall at all, or the waterfall is a solid color (usually purple).

When vetting observations, I think it is more helpful to think of the options like this:

“good” - evidence of the satellite can be seen in the waterfall
“bad” - no evidence of the satellite can be seen in the waterfall
“failed” - no waterfall, or waterfall is one solid color


I would suggest you start with some strong signals like the ones of NOAAs (15, 18 and 19).

Given that in this fairly good pass of NOAA 19, there isn’t any evidence of the satellite’s signal on the waterfall, I would suggest you experiment with different gains and also check that the setup of the ground station is right and ok, for example cables, cables connection etc.

PS I see your station is on client 1.1, there is a new version (1.1.2) with some improvements.

Thanks all, I finally have things up and running. I believe it was the placement of my groundstation and some troubles I was having with my LNA.