When using a VOT to check a VOR receiver, what should the OBS indicate if no error exists?

When checking a VOR receiver using a VOR Test Facility (VOT), the correct indication, if no error exists, is 180° TO and 360° FROM. A VOT provides a means to verify the accuracy of VOR receivers by broadcasting a reference signal.

The VOT transmits a signal that is essentially a precise positioning point for the VOR system. When the VOR receiver is functioning correctly, it should indicate a 180° signal when the OBS (Omni Bearing Selector) is tuned to the VOT frequency and set to "TO," indicating that the aircraft is flying towards the station. Simultaneously, it should indicate 360° when set to "FROM,” signaling an outbound course from the station.

Understanding the expected readings at a VOT is crucial for pilots as it ensures that the navigation equipment is functioning properly, which is essential for safe navigation during flight. Options that include angles like 90° or 270° do not correspond to the correct aspects of what the VOT should indicate under ideal conditions, as these do not align with the VOT's purpose of providing a clear test reference signal for VOR navigation.