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Download QR code; In other projects Appearance. ... United States Frequency Allocations Chart 2011 - The Radio Spectrum.pdf. Archived at archive.org on 2016-10-30.
Land mobile radio systems are widely used by the military. Separate bands in the radio spectrum are reserved for their use. This includes portions of the 30-50 MHz band, and the entire 100-100, 100-100.8, and 540-2400 MHz bands, plus shared use of the 170- 170 MHz band.
Theoretically, the range between two hand-held units on flat ground would be about one or two miles (about 1.5–3 km). Mobile units might have a slightly farther range when mounted on a car roof. A GMRS repeater with an antenna mounted high above the surrounding terrain can extend the usable range to 20 miles or more (30+ km) depending on height.
A repeater controller can be a hardware solution or even be implemented in software. [6] Repeaters typically have a timer to cut off retransmission of a signal that goes too long. Repeaters operated by groups with an emphasis on emergency communications often limit each transmission to 30 seconds, while others may allow three minutes or even ...
Note: Information in the chart has been superseded by the information in File:United States Frequency Allocations Chart 2016 - The Radio Spectrum.pdf, which was downloaded from the US Department of Commerce web site and archived at archive.org.
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. Many amateurs attribute this to the abundance of commercial radio equipment designed for 136–174 MHz and 450–512 MHz that amateurs could easily modify for use on the 2-meter ...
Frequency Coordination is required for a new filing. Major Modifications and Amendments that change or add frequencies, emissions, ERP, Output Power, Antenna Height, Ground Elevation, change location of Base, Fixed, Mobile or Control stations or number of Mobile units and any change to station class.
In the United States, the Multi-Use Radio Service (MURS) is a licensed by rule (i.e. under part 95, subpart J, of title 47, Code of Federal Regulations [1]) two-way radio service similar to the Citizens band (CB).