NDB - non-directional beacons on lighthouses, lightvessels, airports, and from the countryside in and around ICELAND :
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as you can see, this screenshot of an online receiving session in the NDB band from 319 to 419 kHz was made on a summer afternoon in June 2011, thanks to the online receiver at the amateur radio station TF4M / TF4X. Lots of signals to see - and hear...
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