Deep Dive: E7C05
The correct answer is D: A Chebyshev filter. Which filter type has ripple in the passband and a sharp cutoff is a Chebyshev filter. Chebyshev filters have passband ripple but sharp cutoff. For amateur radio operators, this is important for filter design. Understanding this helps when selecting filters.
Why Other Answers Are Wrong
Option A (Butterworth filter): Incorrect. Butterworth has flat passband, not ripple - Chebyshev has ripple. Butterworth isn't the type. Option B (Active LC filter): Incorrect. Active LC filter isn't a specific filter type - Chebyshev is the type with ripple. Active LC isn't the type. Option C (Passive op-amp filter): Incorrect. Passive op-amp filter is contradictory - Chebyshev is the type with ripple. Passive op-amp isn't the type.
Exam Tip
Filter with passband ripple and sharp cutoff = Chebyshev filter. Think 'C'hebyshev = 'C'heap (ripple) but 'S'harp cutoff. Chebyshev filters have passband ripple but sharp cutoff. Not Butterworth (flat passband), not active LC, not passive op-amp - just Chebyshev.
Memory Aid
Filter with passband ripple and sharp cutoff = Chebyshev filter. Think 'C'hebyshev = 'R'ipple + 'S'harp cutoff. Chebyshev filters have passband ripple but sharp cutoff. Important for filter design.
Real-World Example
A filter type with ripple in the passband and a sharp cutoff: It's a Chebyshev filter. Chebyshev filters trade flat passband response for sharper cutoff. This is the type - Chebyshev filter.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E7C
Reference: 2024-2028 Question Pool · E7 - Practical Circuits
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E7C topic.