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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
E7
E7C
E7C09
E7C09:
What is a crystal lattice filter?
A power supply filter made with interlaced quartz crystals
An audio filter made with four quartz crystals that resonate at 1kHz intervals
A filter using lattice-shaped quartz crystals for high-Q performance
A filter with narrow bandwidth and steep skirts made using quartz crystals
E7C01
E7C02
E7C03
E7C04
E7C05
E7C06
E7C07
E7C08
E7C09
E7C10
E7C11
E7C12