Updated: Dec 9, 2025 | Source: 2024-2028 Question Pool | Topic: E7C
E7C06E7C

What are the characteristics of an elliptical filter?

Deep Dive: E7C06

The correct answer is C: Extremely sharp cutoff with one or more notches in the stop band. What are the characteristics of an elliptical filter is extremely sharp cutoff with one or more notches in the stop band. Elliptical filters have sharp cutoff and stop-band notches. For amateur radio operators, this is important for filter design. Understanding this helps when selecting filters.

Why Other Answers Are Wrong

Option A: Incorrect. Gradual passband rolloff with minimal stop-band ripple isn't elliptical - elliptical has sharp cutoff with stop-band notches. Gradual rolloff isn't the characteristic. Option B: Incorrect. Extremely flat passband with gradually rounded stop-band corners isn't elliptical - elliptical has sharp cutoff with stop-band notches. Flat passband isn't the characteristic. Option D: Incorrect. Gradual passband rolloff with extreme stop-band ripple isn't elliptical - elliptical has sharp cutoff with stop-band notches. Gradual rolloff isn't the characteristic.

Exam Tip

Elliptical filter characteristics = extremely sharp cutoff with one or more notches in stop band. Think 'E'lliptical = 'E'xtremely 'S'harp cutoff + 'N'otches. Elliptical filters have sharp cutoff and stop-band notches. Not gradual rolloff, not flat passband - just sharp cutoff with stop-band notches.

Memory Aid

Elliptical filter characteristics = extremely sharp cutoff with one or more notches in stop band. Think 'E'lliptical = 'S'harp cutoff + 'N'otches. Elliptical filters have sharp cutoff and stop-band notches. Important for filter design.

Real-World Example

An elliptical filter: Its characteristics are extremely sharp cutoff with one or more notches in the stop band. Elliptical filters provide the sharpest cutoff but have notches in the stop band. This is the characteristic - sharp cutoff with stop-band notches.

Source & Coverage

Question Pool: 2024-2028 Question Pool

Subelement: E7C

Reference: 2024-2028 Question Pool · E7 - Practical Circuits

Key Concepts

Characteristics Elliptical filter Extremely sharp cutoff One or more notches Stop band

Verified Content

Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E7C topic.