Deep Dive: E7F05
The correct answer is B: At least twice the rate of the highest frequency component of the signal. How frequently must an analog signal be sampled to be accurately reproduced is at least twice the rate of the highest frequency component of the signal. This is the Nyquist sampling theorem. For amateur radio operators, this is important for digital signal processing. Understanding this helps when working with ADCs.
Why Other Answers Are Wrong
Option A: Incorrect. At least half the rate isn't correct - sampling must be at least twice the highest frequency (Nyquist). Half the rate isn't correct. Option C: Incorrect. At the same rate as highest frequency isn't correct - sampling must be at least twice the highest frequency. Same rate isn't correct. Option D: Incorrect. At four times the rate isn't required - sampling must be at least twice the highest frequency. Four times isn't required.
Exam Tip
Sampling frequency for accurate reproduction = at least twice the highest frequency component. Think 'N'yquist = 'N'eed '2'× highest frequency. This is the Nyquist sampling theorem. Not half, not same rate, not four times - just at least twice.
Memory Aid
Sampling frequency for accurate reproduction = at least twice the highest frequency component. Think 'N'yquist = '2'× highest frequency. This is the Nyquist sampling theorem. Important for digital signal processing.
Real-World Example
An analog signal to be accurately reproduced: It must be sampled at least twice the rate of the highest frequency component of the signal. This is the Nyquist sampling theorem - sample at 2× the highest frequency. This is the frequency - at least twice the highest frequency.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E7F
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 E7F topic.