Stockholm radio
Stockholm Radio ( callsign SDJ ) is the oldest and only commercial public Swedish coastal radio station . The radio station is operated by NMSS (Nordic Maritime Services Stockholm AB).
Aviolinx has been the operator of the aeronautical radio service since 2003.
history
The history of the maritime radio service in the Stockholm area begins in 1902. In that year the Royal Swedish Navy began setting up an experimental coastal radio station at the Waxholm Fortress (Vaxholm Radio / SAF) at the entrance to the Baltic Sea from Stockholm. This first radio station was opened to the public maritime service in 1914. The station was operated jointly by the Navy and the Swedish Telecommunications Authority. The station was equipped with an 8 kW Telefunken - extinguishing radio transmitter equipped. In the 1920s, this coastal radio station was equipped with an additional transmitter that could now transmit both telegraphy and telephony signals. At that time, the Navy withdrew as there was a dispute over the funding and management of the station.
The station remained at Waxholm Fortress until 1937. Then a new radio station for medium wave radiotelegraphy and telephony was built on the place Stavsnäs in the archipelago, about 40 km east of the city of Stockholm. At the new station, the transmitting and receiving points were separated: the transmitting point was built on the coast, the receiving radio station was set up on the upper rented floor of a villa in the heart of the village of Stavsnäs. During the war years, the station had a high volume of work at times due to the war-related dangers for commercial shipping and the flow of refugees on the Baltic Sea.
In 1947 a new building for the operational and receiving radio station was built in an area on the outskirts of the village. In the same year, the role of civil coastal radio stations in the Swedish search and rescue system was redefined and "Stockholm Radio" / SDJ was designated the Maritime Rescue Coordination Center (MRCC) for the Swedish part of the Baltic Sea . In 1973 a major reorganization of the transmitter network was carried out. Due to the technical replacement of border wave technology by VHF transmitters, a number of smaller medium wave stations were closed and the VHF and border wave service concentrated on the three remaining radio stations. These were Göteborg Radio (SAG) in the west, Stockholm Radio in the east and Härnösand Radio (SAH) in the north.
In 1979, Stockholm Radio moved to one floor of the regional telecommunications authority building in the south of Stockholm. This move was also part of the association with the shortwave ground / air and point to point station "Enköping Radio" (SAZ). In 1980 the move and the union was complete. VHF radio communications with merchant shipping and weekend sailors in the area of the Stockholm archipelago, together with the tasks of MRCC, became the main business.
In 1992, a study by the maritime authority determined that the MRCC structure should be structured differently. One result was that "Härnösand Radio" (SAH) as the northernmost radio station was no longer necessary. The employees from Härnösand were quickly transferred to other workplaces and the devices are now computer-controlled. A few months after this project, the maritime authority decided to operate the MRCC Gothenburg on its own. This meant that the MRCC was no longer involved in the commercial coastal radio service.
Göteborg Radio's hand-operated cut-off wave, shortwave and VHF services were discontinued and commercial operations moved to Stockholm Radio. The remote control of all devices from Stockholm became functional in autumn 1994. As part of this project, the Stockholm Radio operations center was relocated to a new building about ten kilometers east of Stockholm city center.
Stockholm Radio performs many different tasks today. About 30 employees are employed for the operation and a typical day shift is manned by 5 to 6 radio operators and 3 on the night shift. The volume of traffic has slowly but steadily decreased since mid-1980. Border wave telegraphy experienced a renaissance after the opening of the Iron Curtain and the increase in foreign trade of the Russian Federation via the Baltic Sea ports. Between 1991 and 1995, an average of 40 additional telegrams were accepted. During the high season, during the summer vacation weeks, VHF radio traffic receives around 200–300 VHF calls, and 30 to 50 calls per day during the remaining months.
job
Maritime Rescue Sub-Center
Stockholm Radio works as the MRSC (Maritime Rescue Sub-Center) as an extension of MRCC Göteborg. MRSC Stockholm is responsible for the entire area of the Swedish Search and Rescue Area (SRR). "Stockholm Radio" / MRSC is also the technical center for the VHF DSC (channel 70) and the boundary wave DSC (2187.5 kHz) emergency surveillance system. In addition, Stockholm Radio broadcasts all navigation warnings, weather reports and other safety information, as well as the Swedish NAVAREA information via radio and NAVTEX .
Commercial maritime services
Stockholm Radio offers:
- Security guard at 500 kHz (MRCC)
- Boundary wave telephony
- Boundary wave fishing reports
- Security guard on VHF channel 16 (MRCC)
- VHF telephony
- Shortwave telephony (Maritex Seaphone)
- Use of calls and bookings through the Maritex Radiotelex system
- Maritex customer service and system monitoring outside of normal working hours
The coverage areas for the commercial services are the entire Swedish coastal waters, plus shortwave services for the Atlantic , Indian Ocean and Mediterranean. Other services are traffic control in ports and pilot monitoring.
Aeronautical radio services
Stockholm Radio has also offered a shortwave aeronautical service since the 1970s. The station offers the Long Distance Operational Control Facility (LDOC) for a number of international airlines.