Deep Dive: G4D07
The correct answer is C: Approximately 4 times. How much the power output of a transmitter must be raised to change the S meter reading on a distant receiver from S8 to S9 is approximately 4 times. One S unit is 6 dB, and 6 dB represents a 4:1 power ratio (6 dB ≈ 4×). For amateur radio operators, this helps understand power requirements. Understanding this helps when trying to improve signal reports.
Why Other Answers Are Wrong
Option A (1.5 times): Incorrect. 1.5 times is too little - one S unit (6 dB) requires 4 times power, not 1.5 times. 1.5× would be less than 2 dB. Option B (2 times): Incorrect. 2 times is too little - one S unit (6 dB) requires 4 times power, not 2 times. 2× would be 3 dB. Option D (8 times): Incorrect. 8 times is too much - one S unit (6 dB) requires 4 times power, not 8 times. 8× would be 9 dB (1.5 S units).
Exam Tip
S8 to S9 = approximately 4 times power increase. Think 'S'8 to 'S'9 = 'S'ix dB = '4'× power. One S unit is 6 dB, which represents 4:1 power ratio. Not 1.5, 2, or 8 times - just 4 times.
Memory Aid
S8 to S9 = approximately 4 times power increase. Think 'S'8 to 'S'9 = 'S'ix dB = '4'× power. One S unit is 6 dB, which represents 4:1 power ratio. Significant power increase required.
Real-World Example
Your signal reads S8 at a distant receiver. To increase it to S9, you need to increase power by approximately 4 times (e.g., from 100 watts to 400 watts). One S unit is 6 dB, and 6 dB represents a 4:1 power ratio. This is a significant power increase.
Source & Coverage
Question Pool: 2023-2027 Question Pool
Subelement: G4D
Reference: 2023-2027 Question Pool · G4 - Amateur Radio Practices
Key Concepts
Verified Content
Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G4D topic.