Every 3rd weekend of the month, the Austrian microwavers experiment with propagation and technology at 1 GHz and up. The so-called microwave activity contest takes place on Sunday mornings. The fotos below shows the experimental setups of OE4WOG/P (left) and OE1XTU (right) used on 21.01.2018 for a 10G phone contact. Wolfgang, OE4WOG/P, has setup his rig on a parking spot of Burg Forchtenstein, some 56 km south of TU Wien (see the map). Link parameters: frequency: 10,3681 GHz, polarization: horizontal, modulation: SSB, bandwidth: 3 kHz, link distance: 56km. Transmit power of OE1XTU: 0,26 W, antenna directivity of OE1XTU: 34 dB, resulting in approximately 28 dBW EIRP.
This year’s short wave radio course at TU Wien had 16 participants. We had fun on the longer bands: 160m / 80m / 40m using dipole antennas and a potpourri of modulation formats.
First agenda item in the practical part of the course is the chilly roof visit with antenna inspection. See foto below right.
After we returned to the shack, we experimented with a freshly built Lima-SDR and the SDRadio software on a PC. AM broadcasts can be demodulated with a variety of techniques: the non-coherent envelope detector, the phase-locked product detector which is also known as Exalted-Carrier Selectable-Sideband (ECSS) reception, as well as Upper/Lower Sideband demodulation. These four techniques aren’t equivalent and they sound audibly different.