radio range


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Related to radio range: Radio telemetry

radio range,

geographically fixed radio transmitter that radiates coded signals in all directions to enable aircraft and ships to determine their bearings. An aircraft or ship can determine its line of position and drift if it knows its bearing relative to the radio transmitter and the geographic location of the transmitter. By taking successive bearings on two or more radio ranges the craft can determine its geographic position. Radio ranges are usually unattended; they emit either repeated call letters or steady signals that are periodically interrupted by station identification letters in Morse code. The aircraft or ship obtains its bearings relative to the radio range by picking up these signals with a receiver having a directional antenna, usually a loop antenna. The strength of the signal received depends on the orientation of the antenna relative to the radio range. By varying the orientation of the antenna and observing the changes in signal strength, the bearing of the vehicle can be obtained. When the antenna is driven automatically, the instrument is called an automatic direction finder (ADF). Both manual and automatic direction finders are also called radio compasses, although in aircraft the radio compass usually means an ADF. Another type of radio range called an A-N range transmits two coded signals via directional antennas so that a pilot on one of four fixed courses hears a continuous tone in his or her receiver when the craft's bearing is correct; if it veers off course either a Morse A or N is heard depending on the direction in which the error is made. A very-high-frequency (VHF) omnidirectional radio range transmits a reference signal and another signal that varies from the reference according to the bearing of the receiver. Radio ranging is being made obsolete by the Global Positioning System (GPS), which uses a network of orbiting satellites to precisely locate the position of an aircraft or ship.
References in periodicals archive ?
The center used the Detachment's air-to-ground and voice communications facilities and was operated from the control tower on the radio range frequency.
The Not Soap Radio range is available from Harvey Nichols.
When the user comes back into radio range, the computer begins unlocking the computer, a process that takes about six seconds.
There are pockets of the city that are out of radio range, which may prove to be a factor in this situation.
They did get within radio range and they delivered their antinuclear message that way,'' she said.
Also, for those out of radio range but with access to the Internet, log onto www.
As long as the pilot heard this steady drone, the aircraft was "on the beam" and could fly directly from radio range to radio range even though the ground was not visible.
A shorter radio range enables the user to break the operation into "zones," but this approach increases infrastructure requirements and reduces the radio's ability to reject radio interference.
To begin with, the scientific drill ship stations itself out of helicopter range - no print media can be flown in - and often it is out of radio range.
It's important to position antennas as close as possible to transmitters to provide the maximum radio range.
Interferometry began as a technique inoptical laboratories, using visible light, but its most widespread use in astronomy so far has been in the radio range.
Now customers in Europe and Canada will have a new and cost-effective solution for radar and radio range testing," said Joe Mazzochette, General Manager, Eastern OptX.