Technical Documentation of 50cm 300-900 MHz (P500)
|Type|HEMT LNA, unclooled|
|Channels|2|
|Tsys|300K(Trec~150K)|
|RF Frequency Range|300-900 MHz|
|Band Width RF Filters wide band|300 - 505 MHz|
|->|608 - 685  MHz|
|->|790 - 915 MHz, all parallel|
|Band Width RF Filter 400 MHz band|401 - 405 MHz|
|Band Width RF Filter 600 MHz band|608 - 614 MHz|
|1. Local Oscillator|ULO1 = 1250-1850 MHz|
|1. IF|2100 - 2200 MHz|
|2. Local Oscillator|ULO2 = 1400MHz fixed|
|2. IF|500 - 1000 MHz|
|Polarization|LHC and RHC|
|Calibration|Noise Diode|
|Feed|11-Feed from DRAO|
|Output|300 - 900 MHz direct or 500 - 1000 MHz with IF converter|
====== Block Diagram ======

==== Receiver ====

{{:electronics:rx:techinfo:bsb_geradeaus-rx_50cm_20201211.jpg|}}

==== IF Converter ====

{{:electronics:rx:techinfo:bsb_up_downconverter_vlba_2250_reduziert.jpg|}}


**Comments**
>This receiver is a straight forward 300 MHz to 900 MHz receiver with no down conversion. Due to intensive RFI in this broad frequency band three filter bands are installed in the main part to prevent the system from saturation by the strongest interferer. Nevertheless, there is much more RFI in the band that has to be filtered in the backend. For dedicated projects, switchable RF filters plus LNAs have been inserted for frequencies around 402 MHz and 611 MHz. The filters have a bandwidth of 7 to 10 MHz. For continuum measurements an analogue filtering down converter module to an IF of 100 MHz to 200 MHz for both channels is available.