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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
E6
E6D
E6D04
E6D04:
Which materials are commonly used as a core in an inductor?
Polystyrene and polyethylene
Ferrite and brass
Teflon and Delrin
Cobalt and aluminum
E6D01
E6D02
E6D03
E6D04
E6D05
E6D06
E6D07
E6D08
E6D09
E6D10
E6D11
E6D12
E6D13