Here a little night time Halloween experiment with a recovered radio sonde. I used the QFH Antenna of the Sonde-PCB + an external VK5EME L-Band low noise preamp for testing reception with this omnidirectional antenna. I simply removed the GPS SAW filter and connected a short piece of coax to the former SAW input pins. I was to lazy to modify and reuse the internal preamp on the sonde PCB.

SNR on the waterfall was only around 12-13dB but sufficient for absolutely errorless 1200 baud BPSK bulletin board broadcasted frames on the NCS channel...

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