===Technical Documentation of the 2.8 cm Receiver 10.3 - 10.6 GHz (S28mm)===

|Type|HEMT cooled |
|Channels|4 |
|Receiver Noise|50K |
|Frequency range|10.3 - 10.6 GHz  |
|Polarization|LHC/RHC | 2 horns|
|Calibration|Noise diode |
|Polarimeter | Broadband Polarimeter |
|1st IF| |2.2 - 2.3 GHz | 2.4 - 2.8 GHz |
|  LO1|Valon 5009| fsynt.1 = 4.15 GHz x 2 |fsynt.1 = 3.925 GHz x 2 |
|2nd IF| |100 - 200 MHz |600 - 900 MHz |
|  LO2|Valon 5009| fsynt.2 = 2.1 GHz |fsynt.2 = 1.85 GHz |


{{:electronics:rx:techinfo:2.8cm_rx_bsb_einfach.jpg?900|}}

Simplified {{:electronics:rx:techinfo:2.8cm_rx_bsb_einfach.pdf|Block Diagram}} of the receiver, (RK on 14.4.2021)

{{ :electronics:rx:techinfo:einstellungen_s28mm_für_versionen.pdf |Here}} you can find a table with the settings needed to get access to the IF (in German).

==Comment==

The system comprises 2 feeds, 4 channels and 2 Broadband Polarimeters. 8 data channels, 2 total power and 2 polarization signals per feed are recorded. This total power system is being used in a "software beamswitching" mode to observe extended sources. The feeds are mounted in a row in azimuth direction, having a distance of approximately 3 arcmin. The frequency scheme is fix, the receiver has built-in local oscillators that can't be changed.
The RF-filter is essential to protect against TV-satellites.
The system needs special offline reduction programmes.