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The electromagnetic spectrum between approximately 450 and 470 MHz is used largely for UHF business communications, although this spectrum is not exclusively for business use. In some large metropolitan areas, such as New York, the UHF-T band (between 470 and 512 MHz) is also used due to congestion on the standard VHF or UHF bands.
A radio band is a small frequency band (a contiguous section of the range of the radio spectrum) in which channels are usually used or set aside for the same purpose. To prevent interference and allow for efficient use of the radio spectrum, similar services are allocated in bands.
450–470 MHz: UHF business band, General Mobile Radio Service, and Family Radio Service 2-way "walkie-talkies", public safety; 470–512 MHz: Low-band TV channels 14 to 20 (shared with public safety land mobile 2-way radio in 12 major metropolitan areas scheduled to relocate to 700 MHz band by 2023 [13])
Amateur repeaters in the 144–148 MHz band usually use a 600 kHz (0.6 MHz) separation, in the 1.25-meter band use a 1.6 MHz separation, in the 420–450 MHz band use a 5 MHz separation, and in the 902–928 MHz band use a 25 MHz separation. Systems in the 450–470 MHz band use a 5 MHz separation with the input on the higher frequency.
Commercial radios are typically available in the VHF and UHF frequency bands. 30−50 MHz (sometimes called "Low VHF Band" or "Low Band"), 150.8−174 MHz (sometimes called "High VHF Band" or "High Band"), 450−470 MHz "UHF". Many larger populated areas have additional UHF frequencies from 470 to 512 MHz.
In the 1960s, the UHF 450–470 MHz band was re-allocated to 25 kHz channels. This meant transmitter deviation was reduced to ±5 kHz. This doubled the number of channels available across the entire 450–470 MHz band. Class B Citizens Radio Service channels were re-allocated to other radio services.
American radio amateurs may use a maximum of one watt of radiated RF power, on any ham frequency authorized for data emissions, to control RC models. [10] Canadian radio amateurs may use any amateur frequency above 30 MHz for the control of RC models. [11] Plus or minus 5 MHz is a common repeater frequency offset in the 70 cm band.
Frequency pair (MHz) Band 1 Band 2 Emergency systems 1: 380–383: 390–393 2: 383–385: 393–395 ... 410–430, 450–470, 870–921 Air interface encryption