Proposal for the future of the medium frequency maritime radio band and making 500 kHz a heritage frequency.
Background
From his earliest experiments Guglielmo Marconi sent messages between shore stations and lightships. In 1900 the Marconi International Marine Communication Company was formed to put wireless on board ships and to establish shore stations to serve them. The frequency used was on or around 500kHz
The Berlin Telegraph Convention 1906 nominated 600m (500 kHz) as an operating frequency. It also made SOS the international distress call.
For over 100 years a continuous watch has been kept on 500 kHz. SOS has saved over 10,000 lives (including over 700 on the Titanic), and 500 kHz has made a priceless contribution to Safety of Life at Sea (SOLAS).
The operating system in the medium wave maritime band has been, mainly Morse code, an international signalling system which enables mutual understanding and collaboration between wireless operators of all nations. On 500kHz two silence periods were observed every hour to listen for distant distress signals on 500kHz.
500 kHz was the distress and calling frequency and spot frequencies above it were used as “working” frequencies. Other frequencies in the band were used for direction finding, very important before modern radar. It was the foundation of the maritime communications industry resulting in the refinement of transmitters, receivers and radar equipment.
500 kHz is the only spot frequency in the whole spectrum that can be identified as having life saving historical significance. It can be retained and continue to be used to demonstrate is past role for the benefit of future generations. It is an identifiable location on the wireless spectrum that should be maintained as a heritage site, with its international morse code and own signalling techniques it will continue to be a conduit of peace, cooperation and universal respect.
The frequencies 490kHz and 518kHz are currently used for Navtex a maritime advice service for this reason alone the maritime use of the 405-535kHz maritime band should be maintained with 495-515kHz or 495-505kHz3 nominated a heritage section.
Proposal.
Radiotelegraphy Heritage Frequency (RHF)
That the frequency of 500 kHz be designated as the Radiotelegraphy Heritage Frequency.
Recognising that the two NAVTEX frequencies of 490 kHz and 518 kHz are vital components of GMDSS for the dissemination of Maritime Safety Information and are likely to remain so in the future. Therefore the proposed heritage frequency band is suggested to ensure that there will be no interference with this service. It is proposed that either:-
495 kHz to 505 kHz
or
495 kHz to 513 kHz
be designated as the radiotelegraphy heritage band.
That organisations approach their regional International Telecommunications Union (ITU) representatives to ensure that this proposal is put before the next ITU Telecom World Conference.
That holders of maritime certificates of competence in radiotelegraphy be licenced to use the aforesaid frequencies in the manner laid down in the ITU regulations 1990 and the International Convention for the Safety of Life at Sea (SOLAS) 1988. Such licencees to train new operators in the procedures involved to preserve continuity.
FOR CONSULTATION:-
1. The RHF may be used ONLY as a secondary concession on the strict basis of non-interference when used as laid down as a maritime frequency.
2. That 500 kHz to be retained as the radiotelegraphy calling and distress frequency. That silence periods from xx.15 hours to xx.18 hours and xx.45 hours to xx.48 hours UTC to be observed as originally laid down in the London Convention of 1912.
3. Class of emission
Transmission and reception on the RHF will be by A1A, A2A or H2A emissions only.
4. Radio Personnel – Certificates and Qualifications
4a). Individuals.
Operation on the radiotelegraphy heritage frequency shall only be granted by an authorised body in each signatory state to: -
Persons producing a copy of their former national radiotelegraphy qualification that permits them to operate on the maritime bands. (In the UK this would be a 1st or 2nd Class Postmaster General’s Certificate of Competence in Wireless Telegraphy or a Maritime Radiocommunication General Certificate). Such certificates may have expired but will be considered valid for the purpose of operating on the RHF.
4b). Coast stations and wireless museums
Permanent stations on the sites of shore stations and in wireless museums may be established and operated by persons qualified in above.
Maximum Power level in Watts (dB relative to one Watt) PEP 32W (15dBW).
Signatory states will issue call signs to those persons qualified as outlined in the preceding section. The call signs will be distinct and separate from those issued to commercial stations and to radio amateurs. They will apply only to the radiotelegraphy heritage band and may not be used on any other band.
7. Permanent Stations.
Stations may be set up in the sites of previous shore stations, museum ships, historic wireless sites and other locations with past connection with the maritime radio service. Such sites may be granted call signs that have particular reference to their original call signs.
8. Method of operation.
a). Spot frequencies will be established every kilocycle up or down from 500 kHz within the allocated radiotelegraphy heritage band if possible coinsiding with the former working frequencies.
500 kHz may be used as the calling frequency with the exception of, during silence periods or,
(b) when the frequency is in use for distress purposes.
Method of calling.
a). To an individual station
Stations wishing to operate on the radiotelegraphy heritage band must use the following method when calling another station.
The call sign of the station called, not more than three times;
DE;
The call sign of the calling station, not more than three time.
Example.
GLV GLV GLV
DE
GBGA GBGA GBGA
This initial call should include an indication of the spot frequency proposed as the working frequency. Once contact has been established both stations move to the agreed working frequency.
One such call will be permitted within a two-minute period on 500 kHz. Once established on the spot frequency a call of QRZ? may be made on completion of the initial contact. If no reply is received, then the station returns to listening on 500 kHz.
b). To all stations
Stations wishing to operate on the radiotelegraphy heritage band must use the following method when making a general call to all stations.
The “all stations” abbreviation CQ, not more than three times;
DE;
The call sign of the calling station, not more than three time.
Example.
CQ CQ CQ
DE
GBGA GBGA GBGA
This call may be made on 500 kHz outside silence periods. Only one such call is permitted in a two-minute period. If a reply is received both stations then move to an agreed spot or working frequency for the exchange of traffic.