External remote SDR preselector using Raspberry
- The preselector unit is made by SV1AFN
- Low Noise preamplifier from SV1AFN
- Fixed Attenuator -5db
- The new - Raspberry Pi B+
- Flask server for web remote control of GPIO and preselector
- Apache server for this webpage
- A receiver - any receiver. My receiver is Airspy HF+ connected to Raspberry Pi B+, running Spyserver and listening to sdr://airspypro.no-ip.org:5050/
You can control the preselector via the GPIO server , but keep in mind that Spyserver blocks the bandwidth to 768KHz if more than one listener is connected at the same time. So, please test the preselector, but release the server after your tests, allowing other listeners to QSY.
The receiver is located in Athens, an urban area with RFI problems. It will soon be placed to a more quiet permanent area.
The receiving antenna, Nevada EFW-1, is an End Fed 20m long, 15m. above the ground, with a 9:1 balun.
P.S.1 - Due to radioamateur's activity, receiver may be occasionally off.
P.S.2 - There is not any connected antenna to VHF section.