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The length of an antenna is related to the length of the radio waves used. Due to the short wavelengths, UHF antennas are conveniently stubby and short; at UHF frequencies a quarter-wave monopole, the most common omnidirectional antenna is between 2.5 and 25 cm long.
A directive antenna with moderate gain of about 8 dBi often used at UHF frequencies. Consists of a dipole mounted in front of two reflective metal screens joined at an angle, usually 90°. Used as a rooftop UHF television antenna and for point-to-point data links. Parabolic The most widely used high gain antenna at microwave frequencies and above.
A horn antenna is used to transmit radio waves from a waveguide (a metal pipe used to carry radio waves) out into space, or collect radio waves into a waveguide for reception. It typically consists of a short length of rectangular or cylindrical metal tube (the waveguide), closed at one end, flaring into an open-ended conical or pyramidal ...
222–225 MHz: 1.25 meters (US) (Canada 219–220, 222–225 MHz) amateur radio; 225 MHz and above (UHF): Military aircraft radio, 243 MHz is an emergency frequency (225–400 MHz) AM, including HAVE QUICK, dGPS RTCM-104; Cable television, though not transmitted aerially, uses a spectrum of frequencies overlapping VHF. [13]
This mast has two UHF antennas for receiving signals from different directions. The lower antenna is a bowtie array. The upper antenna is a Yagi design. UHF television broadcasting is the use of ultra high frequency (UHF) radio for over-the-air transmission of television signals. UHF frequencies are used for both analog and digital television ...
The Sudbury transmitting station is a facility for telecommunications and broadcasting transmission at Sudbury, England.It consists of two guyed masts, one, the original, being 165.8 metres (544 ft) high, and a second mast (no longer in service) at 103 metres (338 ft).
The 33-centimeter or 900 MHz band is a portion of the UHF radio spectrum internationally allocated to amateur radio on a secondary basis. It ranges from 902 to 928 MHz and is unique to ITU Region 2 (Americas). [1] It is primarily used for very local communications as opposed to bands lower in frequency.
The 800 MHz frequency band is a portion of the electromagnetic spectrum, or frequency band, that encompasses 790–862 MHz.. Being a part of the spectrum known as "UHF Bands IV and V" (i.e. 470 MHz to 862 MHz) it was allocated by the ITU to Broadcasting as the primary user in Region 1 and was used for analogue television broadcasting before changing to digital terrestrial television in many ...