Deep Dive: E7C11
The correct answer is C: Shape factor. Which of the following measures a filter's ability to reject signals in adjacent channels is shape factor. Shape factor measures how sharp the filter transition is. For amateur radio operators, this is important for filter evaluation. Understanding this helps when evaluating filters.
Why Other Answers Are Wrong
Option A (Passband ripple): Incorrect. Passband ripple doesn't measure adjacent channel rejection - shape factor does. Passband ripple isn't the measure. Option B (Phase response): Incorrect. Phase response doesn't measure adjacent channel rejection - shape factor does. Phase response isn't the measure. Option D (Noise factor): Incorrect. Noise factor doesn't measure adjacent channel rejection - shape factor does. Noise factor isn't the measure.
Exam Tip
Measure of filter's adjacent channel rejection = shape factor. Think 'S'hape 'F'actor = 'S'harpness 'F'actor (measures transition sharpness). Shape factor measures how sharp the filter transition is. Not passband ripple, not phase response, not noise factor - just shape factor.
Memory Aid
Measure of filter's adjacent channel rejection = shape factor. Think 'S'hape 'F'actor = 'S'harpness. Shape factor measures how sharp the filter transition is. Important for filter evaluation.
Real-World Example
A filter's ability to reject signals in adjacent channels: It's measured by shape factor. Shape factor is the ratio of bandwidths at different attenuation levels, indicating how sharp the filter transition is. This is the measure - shape factor.
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.