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Amateur Extra Class: 2020–2024
Today
Sections
E1: Commission's Rules
E2: Operating Procedures
E3: Radio Wave Propagation
E4: Amateur Practices
E5: Electrical Principles
E6: Circuit Components
E7: Practical Circuits
E8: Signals and Emissions
E9: Antennas and Transmission Lines
E0: Safety
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Element 4
E9
E9H
E9H03
E9H03:
What is Receiving Directivity Factor (RDF)?
Forward gain compared to the gain in the reverse direction
Relative directivity compared to isotropic
Relative directivity compared to a dipole
Forward gain compared to average gain over the entire hemisphere
E9H01
E9H02
E9H03
E9H04
E9H05
E9H06
E9H07
E9H08
E9H09
E9H10
E9H11