SAQ transmission of October 24th, 2018
by Alberto I2PHD
SAQ reception of October 24th, 2018 done by Alberto I2PHD in JN45sl, using the Airspy HF+ SDR receiver.
The audio of the transmission can be heard here
The Airspy HF+ was fed from a mini whip antenna, made by Roelof PA0RDT, with a low pass filter to
clean the band, as shown in this photo.
Inside the low pass box there is also a galvanic insulator. The Airspy is modified, the R3 capacitor
is paralleled with a 100nF one.
This is the schematic of the low pass filter :
And this is its Bode plot, as computed by LTSpice :
73 Alberto I2PHD