Today I was testing againg the accuracy of the automatic recording feature. Again I used one Raspberry Pi, two SDR Dongles and two directional antennas. On antenna one, an extra Low Noise Amplifier (LNA) was added to see an improved signal strength. So in red is antenna one with the LNA and in blue antenna two without an external amplification.
Blue: no external amplification
The first 20 minutes the transmitter was switched off, to see how well noise is filtered. The signal strength is clearly increased with the Low Noise Amplifier.