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Explain how a VOR signal provides both bearing and identification.



A VOR (Very High Frequency Omnidirectional Range) signal provides both bearing information to an aircraft and a means of identifying the specific VOR station through two distinct components: the phase relationship between two signals and a Morse code identification signal. The bearing information is provided by the VOR's transmission of two signals: a reference signal and a variable signal. The reference signal is transmitted in all directions at the same phase. The variable signal is transmitted in all directions, but its phase varies depending on the direction from the VOR station. The airborne VOR receiver measures the phase difference between these two signals. This phase difference corresponds to the aircraft's bearing from the VOR station, expressed as a radial. A radial is a line extending outward from the VOR station. For example, if the VOR receiver detects a 30-degree phase difference, the aircraft is located on the 030-degree radial from the VOR. This bearing information allows pilots to determine their position relative to the VOR and navigate along specific courses. The identification of the VOR station is accomplished through a Morse code signal that is transmitted along with the VOR signal. The VOR transmits a unique three-letter Morse code identifier, which pilots can listen to using their VOR receiver's audio output. This identifier confirms that the receiver is tuned to the correct VOR station and that the bearing information is valid. For example, if a pilot tunes to a VOR station and hears the Morse code 'ABC', they can check their aeronautical chart to verify that 'ABC' is indeed the identifier for the intended VOR. This prevents pilots from inadvertently navigating using the signal from a different VOR station. Furthermore, some VORs also transmit a voice identifier. Therefore, the VOR signal provides bearing information through the phase relationship between reference and variable signals and identification through Morse code, ensuring accurate and reliable navigation.