Plain English Meaning

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.

Full 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 on the . Permitted error is ±4°.