Definition
A VOR test facility (VOT) that broadcasts its test signal over the air across the airport surface, allowing pilots to check VOR receiver accuracy from any usable location on the ground rather than only at a designated checkpoint. The signal radiates the 360° radial in all directions, so a correctly tuned and functioning receiver will indicate FROM with a 360° course, or TO with a 180° course, regardless of the aircraft's position on the field. Permitted error is ±4°.
Plain English
A test signal sent out across the airport so a pilot can confirm the VOR receiver in the aircraft is reading correctly before flight. Tune it in, and the instrument should show a fixed reading no matter where you are parked.
Context Anchor
Seen during VOR receiver accuracy checks, especially before instrument flight, when a pilot uses a listed VOT frequency and the authorized reception area for that facility.
Derivation
Radiated' comes from the Latin radiare, 'to send out rays.' Here it describes a test signal that is broadcast outward across the whole airport, in contrast to a ground VOT signal that is only usable at one painted checkpoint spot.
Why Pilots Care
Accurate VOR checks prevent navigation errors that could lead to incorrect course tracking or missed approaches.
Intuition Check
Radiated does not mean radioactive or hazardous here. It means the VOT signal is being broadcast through the air from an antenna.
Example Sentence 1
Before the IFR flight, the pilot tuned the radiated VOT frequency listed in the Chart Supplement and confirmed the receiver was within the four-degree tolerance.
Example Sentence 2
During the instrument proficiency check the examiner had the student verify receiver accuracy using the radiated VOT signal from the ramp.