How to calculate the LNB output frequency from a satellite transponder?

There's a lot of sattelite tracking sites and other information sources that give tunning information as 'Ku band, elevation NN⁰, home transponder = 11015H'.

The question is, what 11015H means? Considering Ku-low band to be 10.70-11.70 GHz, and the universal LNB I have with local oscillator in 9.75 GHz I'm thinking of:

11015H > 11.015GHz Horizontal polarity
11.015GHz - 9.75GHz = 1265KHz //the IF of that transponder in the LNB output


Well, tunning that frequency in fact gave me the proper transponder, but and for Ku-high band? Local oscillator is 10.6 GHz, and using the same math gives me 415KHz -that's out of the expected 950-2150 MHz L band range. What I'm doing wrong?

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1 Answer

My calculations were right - it happens that this is the 'home transponder' - once it is tuned, the stream contains the frequency of the other TPs. A given TP can be only in low or high band, not both (duh!).

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