S-Band receiver
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The S-band receiver has one beam with dual polarizations. The feed has a cooled OMT producing linear polarizations. 
You can select circular polarization synthesized using a hybrid (after the first amplifiers) in the front-end.
Internal switching modes include frequency switching. You can select one of two RF filters: 

* 1.68-2.65 GHz, or
* 2.1-2.4 GHz. 
  
There is choice between two noise diodes with different levels (~10% or ~100% of the system temperature) for flux calibration.

A superconducting notch filter is permanently installed immediately after the first amplifiers and covers the range 2.3-2.36 GHz. 
This filter suppresses interference from the Sirius and XM satellite radio transmissions.