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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
Quick Index
Practice Test
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Element 4
E6
E6B
E6B03
E6B03:
What type of bias is required for an LED to emit light?
Reverse bias
Forward bias
Zero bias
Inductive bias
E6B01
E6B02
E6B03
E6B04
E6B05
E6B06
E6B07
E6B08
E6B09
E6B10
E6B11