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VHF is the first band at which wavelengths are small enough that efficient transmitting antennas are short enough to mount on vehicles and handheld devices, a quarter wave whip antenna at VHF frequencies is 25 cm to 2.5 meter (10 inches to 8 feet) long.
Commercial Private Land Mobile systems are available for businesses in the Business, Industrial, and Land Transportation sectors. Most frequencies are shared with other users. Land mobile radio systems use channels in the VHF or UHF bands, since the antennas used at these short wavelengths are small enough to mount on vehicles or handheld ...
The pointed lower end of the antenna ended in a large ceramic insulator in the form of a ball-and-socket joint on a concrete base, relieving bending moments on the structure. The first, a 665 foot (203 m) half-wave mast was installed at radio station WABC 's 50 kW transmitter at Wayne, New Jersey in 1931.
The base station is one end of a communications link. The other end is a movable vehicle-mounted radio or walkie-talkie. [6] Examples of base station uses in two-way radio include the dispatch of tow trucks and taxicabs. Basic base station elements used in a remote-controlled installation. Selective calling options such as CTCSS are optional.
Inevitably some antennas won't conveniently fit into any one basic type, so the last section on real antennas is an "everything else" category for a few peculiar antennas that don't fit cleanly into any of the categories or subcategories used in this article; for example, random wire antennas and antennas that are laid down on the ground ...
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. There are also a number of specific frequencies, in both the VHF and UHF spectrums, that are for business use; some of these have color-coded names, such as Red Dot or Blue Star.