DGCA CPL ATPL Class VOR VHF Omni Directional Range | Aerial CDI | Doppler VOR | Very High Frequency 

The Principle of Operation, Transmission Details, Identification, Monitoring, Types of VOR, The Factors Affecting Operational Range of VOR, Designated Operational Coverage - (DOC), Factors Affecting VOR Beacon Accuracy, The Cone of Ambiguity