OIRT band
The OIRT band (up to 1960 OIR band) is a frequency range between 65.8 MHz and 74 MHz used for VHF broadcasting in Russia and some neighboring countries . The frequency band dates back to the Soviet Union and was also used in Eastern Europe until the 1990s .
history
The name OIRT band comes from the Eastern European radio and television organization Organization Internationale de Radiodiffusion et de Télévision (OIRT), which was based in Prague . It was considered the "socialist counterpart" to the Western European European Broadcasting Union (EBU). The OIRT also had a television standard for television reception that differed from the CCIR 601 .
In the 1950s, VHF radio began in Czechoslovakia , Poland and Hungary, initially in the CCIR band. In the subsequent period, however, the federal states had to switch to the newly created OIRT band according to the wave plan drawn up by the OIRT . Only in the GDR and in Yugoslavia were transmitters never active in the OIRT band.
After the turnaround in Eastern Europe and the dissolution of the OIRT in 1992, numerous former member countries of the OIRT switched to the VHF band II frequency range from 87.5 to 108.0 MHz, which is used worldwide . To differentiate between the two frequency bands, the terms FM low or FM-OIRT for the OIRT band and FM high or FM-CCIR for the band II are also used. Today in Eastern Europe there are radios on the market that can receive both bands. The frequency grid in the OIRT band is finer at 10 kHz than in the CCIR band, in which 50 kHz is standard.
OIRT broadcasts today
The Czech Republic was the first country to complete the complete upgrade of its VHF transmitters to FM-CCIR. In the Baltic States , Hungary , Romania , Bulgaria and most of the CIS countries, the changeover has largely been completed today. Individual transmitters remained active in the OIRT area.
Today the OIRT tape is still used intensively in Russia , Ukraine , the Republic of Moldova and Belarus . However, these countries have now also released the CCIR band, in which newer programs and private broadcasters in particular have found space. However, this can only be partially used there for radio, because in these countries some television stations broadcast in the frequency range between 76 and 100 MHz.
The frequencies of the OIRT band are used for other purposes in Western Europe. TV channel 4 is in the lower range up to 68 MHz. In Germany, according to the frequency plan of the Federal Network Agency, the frequency range above is assigned to mobile company radio , mobile land radio service and railway radio .
In addition to the OIRT countries, there is also a VHF frequency range that deviates from the global standard in Japan , where radio broadcasts on the frequencies 76 to 90 MHz.