Originally Posted by Troppo
So, at least 500 remains as a safety freq for the maritime service.
Frequencies are worth big bucks these days and at every opportunity those with the money (broadcasters and cellular mobile telephone services) try to obtain a bigger share. The only protection that any of the less profitable services have is by designating frequencies for safety and distress communications. Even then they have to provide extensive evidence that the uses that the frequencies are put to cannot be achieved in any other way.
Amateurs are well down at the bottom of the heap (just) below even the lowly maritime services. So if 500 kHz had not been assigned by the ITU to a safety-related maritime service such as Navtex or DSC, it would have been re-assigned not to the amateurs but to some other service with money to spend. Remember that few of the 200 or so countries that make up the ITU (the organisation that allocates frequencies - not
the IMO) have any active involvement with merchant shipping. Aeronautical comms (they all have airports and nobody wants a 747 dropping out of the sky because of lack of available navaids or safety cmms), broadcasting and cellphones are in every country so pinching lumps of frequency spectrum for those purposes gets all their votes.
Rejoice that it is still in the maritiime community and will continue to make a contribution to safety.