===Technical Documentation of the 6cm Receiver 4.6 - 5.1 GHz (S60mm)===

||Type|HEMT cooled| ||
||Channels|4 | ||
||Receiver Noise|9K | ||
||Frequency range|4.6 - 5.1 GHz | ||
||Polarization|LHC/RHC | 2 horns||
||Calibration|Noise diode| phase cal for VLBI||
||Polarimeter | 2 Broadband Polarimeters ||
||1st IF|2360 - 2860 MHz | ||
||  LO1|Valon 5009| fsynt.1 = 3.73 GHz x 2 (LO1 = 7.46 GHz) | ||
||2nd IF|0.5 - 1 GHz | ||
||  LO2|Valon 5009| fsynt.2 = 2.2 GHz | ||

{{:electronics:rx:techinfo:blockschaltbild_6cmrx_sfk_neu.jpg?1300|}}

Simplified {{:electronics:rx:techinfo:blockschaltbild_6cmrx_sfk_neu.pdf|Block Diagram}} of the receiver, (RK on 24.4.2018)

Detailed {{:electronics:rx:techinfo:6cm_blockdiagram.pdf|Block Diagram}} of the complete receiver, (ZK on 18.5.2018)

==Comment==

This is a 4 channel system with cooled HEMT preamplifiers. It has been constructed for sensitive Continuum, VLBI and Pulsar observations. It is permanently installed in the secondary focus cabin.
The frontend has 2 identical dewars, each comprising one horn, a cooled directional coupler, circular (RHC and LHC) transducer and 2 HEMT amplifiers etc.

The Broadband Polarimeters are placed at the frontend, because the system has a 1 GHz bandwidth.