by Rolf Marschner and Norbert Gabriel, January 2009
(A translation from the original German document)

 * Preserving  radio heritage on 500 kHz*

This summary was composed from input by the 500 kHz Interest Group of the Maritime Radio Operator Association registered in Bremen, Germany and is meant to provide background information for the amateur radio service regarding future use of medium wave frequencies as well as for radio-historical purposes. The intent is to outline the heritage of the maritime distress frequency  of 500 kHz and the extinct profession of the maritime radio operator and a call to preserve the 500 KHz frequency.

For more than a century electromagnetic waves have been used for wireless communication. Due to the nature of radio waves propagating across borders, international coordination for the use of the radio spectrum has been in existence since 1903. To enable as many simultaneous radio applications as possible, rules have been established for the use of different wavelengths. In addition to technical procedures, arrangements for operational rules have been agreed upon. Wireless communication in navigation at sea proved to be the first significant step towards progress.

Before the year 2000, wireless communication at sea was only possible by technically well trained radio operators. For 100 years radio operators on ships and at coast stations kept up the connection between sea and land. This invisible link was of extreme value especially in emergencies. Worldwide, thousands of human lives were saved by using the 500 kHz ( 600 metres) radio distress frequency and manually keyed maritime SOS distress signals. Without the special qualification of radio operators, this could not have been achieved.

The profession of maritime radio operators existed for 100 years in all seafaring countries of the world, but today maritime distress alerting and subsequent distress communication is executed mainly by an automatic system. It is called "Global Maritime Distress and Safety System" (GMDSS). To a great extent it works on the principle of  data transmission and only on a small scale via radio telephony. The data transmission uses shortwave frequencies as well as transmission paths via satellites. But the percentage of false alerts still is too high even though the system was been in operation since 1999. The number of false alarms compared to the time when the distress
system was operated manually, in the opinion view of professional radio operators,  is not acceptable.

At the beginning of the 21st century, the International Telecommunications Union (ITU) no longer required the distinct qualification of being able to send messages by hand using Morse code. Morse code telegraphy in maritime mobile radio service is regarded as a kind of world language enabling international communication without knowledge of foreign languages. This unique language is “spoken” by hand using Morse code and applying many abbreviations and signals as text to overcome language barriers.

The use of manually keyed Morse code is an impressive skill. The application of Morse code simplified communications in all regions and among all nations especially in emergencies when applied on the 500 kHz maritime distress frequency. There has never been another radio frequency in the whole spectrum of electromagnetic waves, which served the sole purpose of saving lives in such a unique manner. Even during the World Wars, the status and purpose of this frequency was never questioned and countries used 500 kHz to communicate for purely humanitarian purposes. Therefore this maritime distress frequency, which has been used for more than 100 years by professional radio operators, represents a radio-historical cultural heritage. In the history of radio, several significant events could be mentioned, however within the relatively new medium of wireless communication this unique use of radio on a world wide basis is unprecedented. The former maritime distress radio frequency and all that is connected with its use, is therefore of exceptional cultural importance. Therefore, the actual frequency of 500 kHz should be preserved for all mankind as some sort of virtual radio memorial.

This request is also in the interest of the International Federation of Shipmasters’ Association (IFSMA). Preservation of radio-historical culture is in full agreement with the UNESCO Convention for the safeguarding of intangible heritage.

However, the 500 kHz frequency remains a subject of debate only within the scope of preparations for the forthcoming World Radio Conference 2011 (WRC 2911) of the ITU. After WRC 2011, it will be reassigned to other spectrum users if no other claims of protection are made. It would once again confirm the good reputation that ITU enjoys among all other international institutions, if they were to choose this one frequency as a radio memorial. After all, (Article 1, Number. 1a) of the ITU Constitution proclaims that it will promote telecommunications for all purposes. Consequently it would be appropriate according to agenda item 1.23 of WRC 2011 to allocate some medium wave spectrum which includes the 500 kHz frequency. Radio amateurs could take over the radio-historic heritage and would be their custodians.

In November 2008 the International Amateur Radio Union Region 1 conference expressed the need for a medium wave allocation, which would include a permanent 500 kHz radio memorial. To keep the radio distress system in the public' memory, it is proposed  that the following major action be taken:

The Amateur Radio Service becomes the curator of the 500 KHz heritage .

Other than professional radio operators today, only radio amateurs will be able to perform and demonstrate radio traffic in the way it was done for more than one hundred years in the maritime mobile radio service. The ability to send Morse code messages by hand is of major importance. A future “museum frequency” of 500 kHz should be used for a practical demonstration of maritime distress radio traffic and for activities related to other events of radio history. In doing so, the contents of the emissions should deal with topics of national as well as international radio history. In addition radio service procedures should be demonstrated, especially those of the maritime mobile radio service. Such radio traffic should be established between ships and coast stations, between ships as well as between stations on land. Furthermore historical radio equipment may be applied to demonstrate formerly used radio applications, transmission modes and various emissions. The occasional transmission of “Grimeton Radio/SAQ” Sweden 17.2 kHz as well as those of “San Francisco Radio/KSM” USA on 500 kHz is an example of demonstrating radio history. Other activities are:

1. Prof. F. Braun Day in September
2. International Marconi day in April
3. International Lighthouse and Lightship Event
4. International Museum Ship Event
5. Maritime Radio Operator Activity Day (Marine Funker - MF)
6. Maritime Radio Day
7. Activity days of other international associations, for example

By creating an official museum frequency embedded in the amateur radio service, the operators will have more opportunities to demonstrate technical and operational intercommunications. Radio operations for historical purposes shall be available to ships operated as museums, maritime museums, telecommunication schools, former coastal stations, general technical museums with radio sections and amateur radio stations. Only persons with proven qualifications may be permitted to transmit in Morse code generated by hand (maritime, amateur, military, police etc.), in order to guarantee proper identification of the transmission. Radio traffic will fall within the services of amateur radio which means that communication for commercial purposes or for third parties is excluded. Cross band operations with other amateur radio stations operating in frequency bands allocated to the amateur radio service are permitted. The “museum frequency” may not be used in connection with amateur radio contests. Any competent person should be permitted to transmit on 500 kHz for historical purposes without necessarily being a qualified amateur radio operator.

If Telecommunication Administrations agree, call signs used for historical emissions could be supplemented by the letter h (as in heritage, historical, historisch, histoire). The former radio silence periods (SP) taking place on the hour on 500 kHz should be observed at least between 12.00 and 13.00 o’clock local time. This means that from 12:15 to 12:18 and 12:45 to 12:48 o’clock local time, no emissions on 500 kHz are allowed, except in case of emergency.

Within the amateur radio operator community, there is an initiative under way to also dedicate a frequency as an amateur radio distress frequency if the amateurs get access to a medium wave band. In ideal case this frequency would be 500 kHz. Since the telegraphy distress signal SOS is not used any more by other radio services it could be taken over by the amateur radio service as well. Up to now the use of SOS in amateur radio service is not allowed and a special amateur radio distress signal does not exist on a world wide basis.

Credits and References:

1) Rolf Marschner and Norbert Gabriel (Germany) , January 2009

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