SDR C/Ku Sniffing? (1 Viewer)

lyn

Active SatelliteGuys Member
May 20, 2012
15
1
Eastern US
the typical L-Band frequencies, so usually 950 to 2050 MHZ. I'm not sure what the upper limit of the Airspy R2 is. My RTL-SDR cuts at about 1700 MHZ

If you want to check the beacons, many are published here: http://frequencyplansatellites.altervista.org/Beacon-Telemetry_Americas.html and here: http://frequencyplansatellites.altervista.org/Beacon-Telemetry_Atlantic.html

you then have to convert to L-Band. by subtracting the LO frequency (or from the LO frequency if C-Band)
so for example a beacon at 3950 MHz would be seen by the SDR as 5150-3950 = 1200 MHz
Note that it's not uncommon that the beacons be on circular polarization on an otherwise linearly polarized satellite, or vice versa

you should also be able to see narrow transponders on the spectrum in SDR#

Looking at the manual for my Chaparral CR-10 c/ku band receiver that I mainly use as a dish mover for my FTA receiver, I notice that it has separate outputs for Base Band and Data. The BaseBand output has settings for Deemphasized, Emphasized, Unclamped and Clamped. There is also a terrestrial interference filter that can be switched in. Would using Baseband or Data output to an SDR receiver give better results than using the Loop Out on the FTA receiver?
 

Brct203

SatelliteGuys Pro
Dec 24, 2016
1,152
1,117
Connecticut
Looking at the manual for my Chaparral CR-10 c/ku band receiver that I mainly use as a dish mover for my FTA receiver, I notice that it has separate outputs for Base Band and Data. The BaseBand output has settings for Deemphasized, Emphasized, Unclamped and Clamped. There is also a terrestrial interference filter that can be switched in. Would using Baseband or Data output to an SDR receiver give better results than using the Loop Out on the FTA receiver?
no I don't think that would work. The baseband on an analog receiver was the result of the first FM demodulation of the analog signal, in which you would have found the color subcarrier at 3.58 or 4.43 MHz and the the audio subcarriers at 6.20 and 6.80 for most US signals and often 6.65 or 6.50 for European signals. Now with digital stuff, I would just expect the baseband to be an unusable mess
 

moonbase

Well-Known SatelliteGuys Member
Pub Member / Supporter
Jul 16, 2015
33
16
UK
There are a lot of very narrow bandwidth C-Band frequencies on 95.0W (Galaxy 3C). Has anyone took a look at this satellite in the C-Band range with some type of SDR device?
 

Inclined Orbit

SatelliteGuys Pro
Jan 2, 2018
376
201
Los Angeles
There are a lot of very narrow bandwidth C-Band frequencies on 95.0W (Galaxy 3C). Has anyone took a look at this satellite in the C-Band range with some type of SDR device?
I had to closely monitor everything on G3C from the day it went live at my last job. There is a special 10MHz wide Ku transponder that shuffled data and telephone calls between a US site and several Latin America sites. You could see it all with an SDR but would need an appropriate modem to demodulate things and proper equipment to see the date or hear the phone calls. I believe this has been abandoned in the last several years and the traffic has moved to another satellite.

Otherwise I can't think of anything that can be received and actually heard off G3C with an SDR.
 

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