Deep Dive: G4D06
The correct answer is A: 6 dB. The change in signal strength typically represented by one S unit is 6 dB. Each S unit represents approximately 6 dB change in signal strength. For amateur radio operators, this helps understand S meter readings. Understanding this helps when comparing signals.
Why Other Answers Are Wrong
Option B (12 dB): Incorrect. 12 dB is too much - one S unit is approximately 6 dB, not 12 dB. 12 dB would be two S units. Option C (15 dB): Incorrect. 15 dB is too much - one S unit is approximately 6 dB, not 15 dB. 15 dB would be 2.5 S units. Option D (18 dB): Incorrect. 18 dB is too much - one S unit is approximately 6 dB, not 18 dB. 18 dB would be three S units.
Exam Tip
One S unit = 6 dB change. Think 'S' unit = 'S'ix dB. Each S unit represents approximately 6 dB change in signal strength. Not 12, 15, or 18 dB - just 6 dB per S unit.
Memory Aid
One S unit = 6 dB change. Think 'S' unit = 'S'ix dB. Each S unit represents approximately 6 dB change in signal strength. Standard S meter calibration.
Real-World Example
A signal increases from S5 to S6. This represents a 6 dB increase in signal strength. If it increases from S5 to S7, that's 12 dB (two S units). Each S unit represents approximately 6 dB change - this is the standard S meter calibration.
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.