Ads
related to: uhf vs vhf walkie talkie antenna adapters for rv tv stands
Search results
Results from the WOW.Com Content Network
The VHF band is the first band at which efficient transmitting antennas are small enough that they can be mounted on vehicles and portable devices, so the band is used for two-way land mobile radio systems, such as walkie-talkies, and two way radio communication with aircraft and ships (marine radio).
TV antenna manufacturers often rated their top-of-the-line "deep-fringe" antenna models with phrases like "100 miles VHF/60 miles UHF" if the antenna included UHF reception at all. (In the practice of electrical engineering, the frequency range in which an antenna is to be used is an important factor in its design.)
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 [12])
Since VHF and UHF frequencies are desirable for many uses in urban areas, in North America some parts of the former television broadcasting band have been reassigned to cellular phone and various land mobile communications systems. Even within the allocation still dedicated to television, TV-band devices use channels without local broadcasters.
Small monopoles ("whips") are used as compact, but low-gain antennas on portable radios in the HF, VHF, and UHF bands. Whip Type of antenna used on mobile and portable radios in the VHF and UHF bands such as FM "boom boxes", consists of a flexible rod, often made of telescoping segments
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 transceivers. Transmitter power is usually limited to a few watts, to provide a reliable working range on the order of 3 to 20 miles (4.8 to 32 km) depending on terrain.
The connector reliably carries signals at frequencies up to 100 MHz. [1] The coupling shell has a 5 / 8 inch 24 tpi UNEF standard thread. [4] The most popular cable plug and corresponding chassis-mount socket carry the old Signal Corps labels PL-259 (plug #259) and SO-239 (socket #239). [12]
The rubber ducky antenna (or rubber duck aerial) is an electrically short monopole antenna, invented by Richard B. Johnson, that functions somewhat like a base-loaded whip antenna. It consists of a springy wire in the shape of a narrow helix , sealed in a rubber or plastic jacket to protect the antenna. [ 1 ]
Ads
related to: uhf vs vhf walkie talkie antenna adapters for rv tv stands