Low level signals with RTL-SDR, more gain?

SatNOGS
1

Hi, having low signals level with Satnogs/RTL-SDR. Even passes with the NOAA sats show barely anythings on the waterfall.
Satnogs RF gain is set at 32.8. Antenna Diamond X30-N, cable 6m RG213. Lots of signals running the RTL-SDR with SDR++ so hardware seems ok.
SoapySDRUtil --probe is not working “command not found”

Any ideas??

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for reference, obs and station.

regarding command not found, this is true if you follow the old troubleshooting guide and is on the new docker stack.

the antenna is made for terrestrial contacts, as can be seen in the gain plot.

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this somewhat compensates for weaker signals on the horizon and stronger overhead. but they’re often quite deaf to signals at high elevation angles.
it is also not made for 137MHz, so the gain and pattern at that frequency is probably unknown.

1 Like
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Hi SA2KNG,
Thanks for the response. Had the idea that NOAA sats would give signals that could be read with less than perfect antenna’s. But seems this is not the case. Considering that, the whole Satnogs thing is imho only interesting for some lucky ones with dedicated tracking antennas. Pity this is not mentioned in the wiki’s…

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The wiki also shares information on what type of antenna’s that should give good observations.

My guess is that currently most are using stationary antenna systems.

Because NOAA apt is also using circular polarization, have a look for QFH or Turnstile models.

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I think there’s some stats for this, but it is not at all some minimum requirement.
Jan, myself and many others have put a lot of work in their (stationary antenna) stations and the results speak for themselves.
Example of observations with data uploaded on my station 1864
Getting a station up and running is pretty much the first step. Improving reception by experimenting with antennas, filters and preamps is what starts then and there, and many enjoy this part immensely as it can be very rewarding.

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