L-Band receiver
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This receiver has one beam on the sky, with dual polarizations. The feed has a cooled OMT producting linear polarizations. You can select circular polarization which is synthesized using a hybrid (after the first amplifiers) in the front-end. Allowed internal switching modes are frequency and/or polarization switching. You can select one of four RF filters: 

* 1.1-1.8 GHz
* 1.1-1.45 GHz
* 1.3-1.45 GHz
* 1.6-1.75 GHz

A notch filter between 1.2 and 1.34 GHz is available to suppress interference from a nearby Air Surveillance Radar. There is a choice between two noise diodes with different levels (~10% or ~100% of the system temperature) for flux calibration.