Considering 4630KHz emergency communication of amateur radio stations in frequent natural disasters

I used to be engaged in telecommunications in the Self-Defense Forces, and I decided to edit and move what I posted on a miscellaneous blog, which is more suitable for amateur radio than a miscellaneous blog .

　　　　　　　emergency communication frequency

Morse communication　 (F2) is also possible in the FM system
*1　4630KHz is exclusively for emergency communication contact settings, and can directly communicate with government agencies such as the National Police Agency, the Self-Defense Forces, and the Japan Coast Guard . The communication frequency is limited to call and answer contact settings, and must be changed to another frequency within the FM division to continue emergency communication.

frequent natural disasters

Many natural disasters occurred this year, including the Northern Osaka Earthquake, July 2018 heavy rain, Typhoon No. 20, Typhoon No. 21, Typhoon No. 24, and the Hokkaido Eastern Iburi Earthquake.
Typhoon No. 24 caused the largest power outage in the Heisei era, and we were forced to live inconveniently for a long time.

Radio amateurs, who are allowed to use radio waves, which are a limited and precious resource, at an extremely low fee, were made to think about what they could do in such a situation.
The first thing that comes to mind is emergency communications.

Difference between distress communication and emergency communication

Distress communication is communication when a ship's maritime accident or a serious crisis of an aircraft occurs.
Emergency situations in mountain climbing are generally described as distress, but according to radio law, they are emergency communications.
The telegraph distress signal "SOS" is well known to the general public through movies, etc., but the emergency communication "OSO" is not well known unless you are a radio operator.

Distress communication and emergency communication are handled differently by the Radio Law.
In general, emergency communication is basically communication within the scope of the license, except that use other than the intended purpose (emergency communication) is permitted for communication matters.
Distress communication, on the other hand, is a top-priority communication that is permitted even if the frequency, output, model, etc. exceed the range of the license as well as the communication items.

Definition of distress communication
Radio communication by means of a distress signal or other method specified by an ordinance of the Ministry of Internal Affairs and Communications when a ship or aircraft is in serious and imminent danger.
(Please note that accidents such as mountain climbing are not included.)

When conducting distress communication,
it is possible to communicate beyond the scope described in the license of the radio station with respect to "purpose of communication", "communication partner" and "communication items". (Article 52 of the Radio Law)
It is possible to communicate beyond the range described in the license of the radio station with respect to "place of installation of radio equipment", "identification signal", "type of radio wave" and "frequency of radio wave". (Article 53 of the Radio Law)
Regarding "antenna power" (output), communication is possible beyond the range described in the radio station license. (Article 54 of the Radio Law)
In addition, radio stations whose "permissible operation time" is restricted can be operated outside that time. (Article 55 of the Radio Law)

Definition of
Emergency Communication communication made for the purpose of saving lives, relieving disasters, securing traffic communications, or maintaining order when it is extremely difficult to

Emergency communication must be within the range of "place of installation of radio equipment", "identification signal", "type of radio wave", "frequency of radio wave" and "antenna power" which have been licensed in advance.

Only the "purpose of communication", "communication partner" and "communication matters" can be communicated beyond the range described in the radio station license.

4630KHz in amateur radio stations

The total number of amateur radio stations, which continues to decline, is 420,281 stations.
Of these, 43,495 stations are licensed for 4630KHz (searched 2018/06/17), which
is almost 10%.

Since I had been skeptical about 4630KHz amateur radio stations for a long time, I decided to write an article about it the day before the Osaka earthquake, so I searched for information on radio stations, etc. of the Ministry of Internal Affairs and Communications.
I couldn't find anything other than amateur radio stations, but I think there are few licensed stations.
It is interesting to see how many of the Self-Defense Forces, National Police Agency, Japan Coast Guard, Meteorological Agency, and Coastal Bureau have licenses.

In 1949, when emergency communication communication setting frequencies were stipulated as follows, amateur radio stations were not yet permitted.
It resumed in 1952, when the San Francisco Peace Treaty came into force, ending the state of war with the Allies under international law and restoring sovereignty.

At that time, most of the transmitters and receivers for amateur stations were self-made, so it is thought that it was not so difficult to comply with this designation.
After that, almost all amateur radio stations started to use manufacturer-made equipment, and there was a time when domestic radio manufacturers did not have anything that corresponded to this designation, probably because the frequency was far from the hamband.

After that, manufacturers (for example, Icom) realized the significance of this designation and made it possible to send, and now it is possible to jointly operate with domestic set manufacturers.
For this reason, I think that most people apply for it while saying, "Let's get what we can get."

History of emergency communication frequencies

1949 (Showa 24) Private wireless telegraph and telephone regulations were revised, and the wireless telegraph law that was enforced at that time stipulated that wireless telegraph 4,200 kc (Kc notation at that time, equivalent to current KHz) was to be used for emergency communication. it was done.
The Radio Law was enacted in June 1950 (Showa 25), and the Wireless Telegraph Law was abolished.
1953 (Showa 28) ``Emergency stations that communicate by wireless telegraph must be able to send and receive A1 radio waves of 4,200 kc.''

1954 (Showa 29) The emergency communication frequency was changed from 4,200kc to 4,630kc.
4630KHz is a representative frequency established by the government as amateur radio is recognized as a hobby that is useful to society.
According to the Radio Law, the Self-Defense Forces, the National Police Agency, the Japan Coast Guard, the Japan Meteorological Agency, the Coastal Station, etc. and his amateur radio stations are licensed for the purpose of systematically conducting emergency communications using the same frequency as the emergency communication communication setting frequency.
For this reason, we hams also operate this public frequency together with business radio stations.

Is 4630KHz necessary for amateur radio stations?

As mentioned above, radio equipment manufacturers have come to support, and a large number of amateur radio stations have applied and been approved.
However, how many people can actually respond to emergencies?
How many people have an antenna for 4630KHz
? So, he might go out to 4630KHz forcibly.

Assuming that it is possible to transmit and receive at 4630KHz, is it possible to correspond with the Self-Defense Forces, the National Police Agency, the Japan Coast Guard, the Meteorological Agency, and the Coastal Station other than amateur radio stations? Naturally, messages with these stations will be in Japanese
. .
Isn't it just confusing if you don't follow the prescribed format?

In that case, the other party of the emergency communication is limited to the amateur radio station.
When dealing with amateur radio stations, there is no need to use 4630KHz.
Amateur radio frequencies, which many amateur radio stations will be listening to in an emergency, are sufficient.
Only by operating amateur radio stations on amateur radio frequencies can the features of amateur radio stations that can be operated even during power outages such as handheld and mobile machines be demonstrated.

The emergency communication manual for amateur radio stations is available on the JARL website, so I will paste it here.
For the above reasons, the authorities have not applied for 4630KHz.