Updated: Dec 9, 2025 | Source: 2023-2027 Question Pool | Topic: G4D
G4D04G4D

What does an S meter measure?

Deep Dive: G4D04

The correct answer is C: Received signal strength. What an S meter measures is received signal strength. S meters indicate how strong received signals are, typically on a scale of S1-S9 plus dB over S9. For amateur radio operators, this helps assess signal quality. Understanding this helps when reading S meters.

Why Other Answers Are Wrong

Option A: Incorrect. S meters don't measure carrier suppression - that requires specialized equipment. Carrier suppression is a transmitter parameter. Option B: Incorrect. S meters don't measure impedance - that requires impedance meters. Impedance is a different parameter. Option D: Incorrect. S meters don't measure transmitter power output - that requires power meters. Power output is a transmitter parameter.

Exam Tip

S meter measures = received signal strength. Think 'S' meter = 'S'trength meter (received signal). Indicates how strong received signals are, typically S1-S9 plus dB over S9. Not carrier suppression, not impedance, not power output - just received signal strength.

Memory Aid

S meter measures = received signal strength. Think 'S' meter = 'S'trength meter. Indicates how strong received signals are, typically S1-S9 plus dB over S9. Helps assess signal quality and propagation.

Real-World Example

You receive a signal and the S meter reads S7. This indicates the received signal strength is S7 (moderately strong). If it reads S9+20 dB, the signal is very strong (20 dB over S9). S meters help you assess signal quality and propagation conditions.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G4D

Reference: 2023-2027 Question Pool · G4 - Amateur Radio Practices

Key Concepts

S meter Received signal strength Signal strength Receiver features

Verified Content

Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G4D topic.