The bandwidth of a band-pass filter is measured between what two frequencies?

Q: The bandwidth of a band-pass filter is measured between what two frequencies?

The correct answer is A: Upper and lower half-power. The correct answer is A: Upper and lower half-power. The bandwidth of a band-pass filter is measured between the upper and lower half-power frequencies. Bandwidth is measured at the -3 dB points (half-power points) on both sides of the passband. For amateur radio operators, this is a fundamental filter parameter. Understanding this helps when designing filters.

Previous Next

Deep Dive: G7C14

The correct answer is A: Upper and lower half-power. The bandwidth of a band-pass filter is measured between the upper and lower half-power frequencies. Bandwidth is measured at the -3 dB points (half-power points) on both sides of the passband. For amateur radio operators, this is a fundamental filter parameter. Understanding this helps when designing filters.

Why Other Answers Are Wrong

Option B (Cutoff and rolloff): Incorrect. Cutoff and rolloff aren't the bandwidth measurement points - bandwidth is measured between half-power points, not cutoff/rolloff. Cutoff/rolloff aren't the terms. Option C (Pole and zero): Incorrect. Pole and zero are mathematical concepts (filter design), not bandwidth measurement points. Poles/zeros aren't the measurement points. Option D (Image and harmonic): Incorrect. Image and harmonic are interference terms, not bandwidth measurement points. Image/harmonic aren't the measurement points.

Exam Tip

Band-pass filter bandwidth = measured between upper and lower half-power frequencies. Think 'B'andwidth = 'B'etween 'H'alf-power points. Bandwidth is measured at -3 dB points (half-power) on both sides of passband. Not cutoff/rolloff, not pole/zero, not image/harmonic - just half-power points.

Memory Aid

Band-pass filter bandwidth = measured between upper and lower half-power frequencies. Think 'B'andwidth = 'B'etween 'H'alf-power. Bandwidth is measured at -3 dB points on both sides of passband. Standard bandwidth measurement.

Real-World Example

A band-pass filter: The passband extends from the lower half-power frequency (-3 dB point) to the upper half-power frequency (-3 dB point). The bandwidth is the difference between these two frequencies. This is how band-pass filter bandwidth is measured - between the upper and lower half-power points.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G7C

Reference: 2023-2027 Question Pool · G7 - Practical Circuits

Key Concepts

Band-pass filter Bandwidth Upper and lower half-power -3 dB points

Official Pool Source

Question text and answer key are synchronized with the current NCVEC General Class pool and mapped to the G7C topic.