ARLA/CLUSTER: Teste TX em DRM por radioamadores suíços

[João Gonçalves Costa]

Amateur radio DRM trial in Sottens

The Radio Amateurs Vaudois club has been granted the experimental use of the old Sottens MW broadcast antenna. A video shows a test using digital radio DRM.

The YouTube description reads

Amateur radio DRM test transmission from HB9MM in Sottens, Switzerland using a phased out 188 meters high MW antenna. The DRM test setup based on Software Defined Radio consisted of a PC running Spark software for DRM signal generation, a USRP for RF output, a mini-circuits Gali74 amplifier, an unknown brand pre-amplifier and a final 1kW Motorola amplifier normally designed for SSB but running at 150-200W. The signal transmitted was an audio loop announcing the special callsign HE3OM in English and French. Two constellations have been tested 16QAM and 64QAM both in mode B (for skywave propagation).

The signal could be received throughout Europe with reports even from Sweden or Latvia.

Watch Amateur Radio DRM Trial In Sottens
http://www.youtube.com/watch?v=LwOQJY9xzSc

It is understood the transmission bandwidth was 4.5kHz and frequencies of 7.180MHz and 3.780MHz were used during tests on Feb 13 and 20, see
http://bclnews.blogspot.com/2011/02/drm-trial-transmission-from-sottens.html

The group's webpage indicates tests on 160m, 80m and 137.3kHz 
http://www.hb9mm.com/sottens-en?set_language=en

HB9MM Radio Amateurs Vaudois (RAV) in Google English
http://tinyurl.com/HB9MM-RAV