|Raspberry Pi Hat|
The Live System can be accedes here http://rfnoise.amsatsa.org.za/
I Developed a rf noise monitoring system and there was a need to standardize on an active antenna for the system.
My thinking was sins most Remote Stations is Raspberry Pi with RTL-SDR dongles I felt developing a front end power injector with Galvanic isolation from active antenna with the necessary RF filters.
I also had a requirement to resolve the rtl-sdr dongle front end filter problem.
There is an Rf image on center frequency 14.2 Mhz.
I then Developed a Low and High band pass filters on the same PI HAT that can be switched via IO pins on Pi.
Here is the circuit diagram of my design with out the Active Antenna.
|Raspberry Pi HAT with Filters,Isolation and Power injection|
Filter design details.
|High Pass Filter|
|Low Pass Filter|
I will work on an active Antenna board.
|3D View of Boards|
|RF Noise Filter HAT for Raspberry Pi|
All seems to work fine will add spectrum Analyses details.