Deep Dive: G3C06
The correct answer is B: Signals have a fluttering sound. A characteristic of HF scatter is that signals have a fluttering sound. Scatter signals are created by multiple reflection paths, causing rapid signal variations that sound like fluttering. For amateur radio operators, this distinctive sound helps identify scatter propagation. Understanding this helps recognize scatter signals.
Why Other Answers Are Wrong
Option A: Incorrect. Scatter signals don't have high intelligibility - they're often distorted and hard to copy. High intelligibility isn't a scatter characteristic. Option C: Incorrect. Scatter signals don't have very large, sudden swings - they have rapid, small variations (fluttering), not large swings. Fluttering is the key characteristic. Option D: Incorrect. Scatter propagation doesn't occur only at night - it can occur at any time. Time isn't the defining characteristic.
Exam Tip
HF scatter characteristic = fluttering sound. Think 'S'catter = 'S'ignal 'S'cattered = 'S'ound 'S'cattered (fluttering). Signals have rapid variations from multiple reflection paths, creating fluttering sound. Not high intelligibility, not large swings, not night-only - just fluttering.
Memory Aid
HF scatter characteristic = fluttering sound. Think 'S'catter = 'S'ignal 'S'cattered = 'S'ound 'S'cattered. Signals have rapid variations from multiple reflection paths, creating distinctive fluttering sound. Key identifier of scatter propagation.
Real-World Example
You receive an HF scatter signal. It has a distinctive fluttering sound - rapid, small variations in signal strength caused by multiple reflection paths. The signal may be weak and distorted, but the fluttering characteristic identifies it as scatter propagation. This is different from normal skywave signals.
Source & Coverage
Question Pool: 2023-2027 Question Pool
Subelement: G3C
Reference: 2023-2027 Question Pool · G3 - Radio Wave Propagation
Key Concepts
Verified Content
Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G3C topic.