These satellites normally have a transponders supporting a number of different frequency payloads, including UHF / S & X Band. Its worth noting that all these satellites are geo-stationary, operating in a fixed position above the equator.
Below is a screenshot from the traces I took today of satellites operating in the UHF band.
This screenshot above covers a number of different satellites, illustrating the different transponder outputs, signal bandwidths and modulation types. The signals illustrated above have been identified as the following:
243.625 - ComSatBW-2 38KHz Channel - Operating at 13.2 East
243.785 - MilSat 2-3 50KHz Channel - Operating at 30.0 East
243.8225 - Milsat 1 50KHz Channel - Operating at 39.1 West
243.995 - US UFO F2 8x 6KHz Channels - Operating at 28.3 East
244.075 - US UFO F7 8x 6KHz Channels - Operating at 23.3 West
244.185 - US FltSatCom F8 5x 6KHz Channels - Operating at 15.1 West
The next screenshot below is a slightly wider panoramic display, showing around 8MHz of sprectrum in the upper part of the 240-270MHz band. This shows some good traces for the following satellites:
269.750 - UFO F2 - 34KHz Channel
268.675 - SDS3-F2 - 25KHz Channel
265.350 - UFO F2 - 34KHz Channel
268.000 - Sircal 1b - 5x 34KHz Channels
A few notes on my monitoring system setup. In order to capture the above traces, I used the following kit:
AirSpy SDR Receiver
SDR# Software
RFBay LNA-1000 (10-1000MHz 30db Amplifier)
Trivec 2030 UHF MilSat Antenna
Acknowledgements:
Many thanks to the following websites for their supporting content and details:
http://www.uhf-satcom.com/
http://www.satellitenwelt.de/uhfmilsat.htm
