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Very high frequency (VHF) is the ITU designation [1] [2] [3] for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter.
The original allocation of channels consisted of only channels 1 to 28 with 50 kHz spacing between channels, and the second frequency for full-duplex operation 4.6 MHz higher. Improvements in radio technology later meant that the channel spacing could be reduced to 25 kHz with channels 60 to 88 interspersed between the original channels.
The Pan-American television frequencies are different for terrestrial and cable television systems. Terrestrial television channels are divided into two bands: the VHF band which comprises channels 2 through 13 and occupies frequencies between 54 and 216 MHz, and the UHF band, which comprises channels 14 through 36 and occupies frequencies between 470 and 608 MHz.
Five 2.8 kHz-wide channels are available in the U.S., centered on 5.332, 5.348, 5.368, 5.373, and 5.405 MHz. Since most radios in SSB mode display the (suppressed) carrier frequency, in USB mode the dial frequencies would all need to be set 1.5 kHz lower. Voice operation is generally in upper sideband mode, which is mandatory in the U.S. . The ...
Amateur use of VHF and UHF allocations exploded in the late 1960s and early 1970s as repeaters started going on the air. Repeater use sparked a huge interest in the 2-meter and 70-centimeter (420–450 MHz) bands; however, this interest never fully found its way into the 1.25-meter band.
FM channel 200, 87.9 MHz, overlaps TV 6. This is used only by K200AA.; TV 6 analog audio can be heard on FM 87.75 on most broadcast radio receivers as well as on a European TV tuned to channel E4A or channel IC, but at lower volume than wideband FM broadcast stations, because of the lower deviation.
HF's position in the electromagnetic spectrum.. High frequency (HF) is the ITU designation [1] [2] for the band of radio waves with frequency between 3 and 30 megahertz (MHz). It is also known as the decameter band or decameter wave as its wavelengths range from one to ten decameters (ten to one hundred meters).
The 90–108 MHz section was used for analog VHF TV Channels 1, 2 and 3 (each NTSC television channel is 6 MHz wide). The narrowness of the Japanese band (19 MHz compared to slightly more than 20 MHz for the CCIR band) limits the number of FM stations that can be accommodated on the dial with the result that many commercial radio stations are ...