Deep Dive: E6D09
The correct answer is C: Ferrite beads. What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier is ferrite beads. Ferrite beads suppress parasitic oscillations at VHF/UHF. For amateur radio operators, this is important for amplifier stability. Understanding this helps when stabilizing amplifiers.
Why Other Answers Are Wrong
Option A (Electrolytic capacitors): Incorrect. Electrolytic capacitors aren't parasitic suppressors - ferrite beads are. Electrolytic capacitors isn't the device. Option B (Butterworth filters): Incorrect. Butterworth filters aren't parasitic suppressors - ferrite beads are. Butterworth filters isn't the device. Option D (Steel-core toroids): Incorrect. Steel-core toroids aren't used - ferrite beads are used as parasitic suppressors. Steel-core toroids isn't the device.
Exam Tip
VHF/UHF parasitic suppressors at HF amplifier = ferrite beads. Think 'F'errite 'B'eads = 'F'ilters 'B'and (parasitic suppression). Ferrite beads suppress parasitic oscillations at VHF/UHF. Not electrolytic capacitors, not Butterworth filters, not steel-core toroids - just ferrite beads.
Memory Aid
VHF/UHF parasitic suppressors at HF amplifier = ferrite beads. Think 'F'errite 'B'eads = 'P'arasitic suppression. Ferrite beads suppress parasitic oscillations at VHF/UHF. Important for amplifier stability.
Real-World Example
VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier: Ferrite beads are commonly used. Ferrite beads add resistance to VHF/UHF signals, suppressing parasitic oscillations. This is the device - ferrite beads.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E6D
Reference: 2024-2028 Question Pool · E6 - Circuit Components
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E6D topic.