G4C03: SSB interference: What sound is heard from an audio device

Q: What sound is heard from an audio device experiencing RF interference from a single sideband phone transmitter?

The correct answer is C: Distorted speech. The correct answer is C: Distorted speech. The sound heard from an audio device experiencing RF interference from a single sideband phone transmitter is distorted speech. SSB signals are demodulated by the audio device's non-linear circuits, producing distorted audio. For amateur radio operators, this is a common RFI symptom. Understanding this helps identify SSB interference.

Updated: Dec 9, 2025 | Source: 2023-2027 Question Pool | Topic: G4C

G4C03G4C

What sound is heard from an audio device experiencing RF interference from a single sideband phone transmitter?

Previous Next

Deep Dive: G4C03

The correct answer is C: Distorted speech. The sound heard from an audio device experiencing RF interference from a single sideband phone transmitter is distorted speech. SSB signals are demodulated by the audio device's non-linear circuits, producing distorted audio. For amateur radio operators, this is a common RFI symptom. Understanding this helps identify SSB interference.

Why Other Answers Are Wrong

Option A: Incorrect. SSB interference doesn't produce a steady hum - that's more typical of carrier interference. SSB produces distorted speech, not hum. Option B: Incorrect. SSB interference doesn't produce on-and-off humming or clicking - that's more typical of CW interference. SSB produces continuous distorted speech. Option D: Incorrect. SSB interference doesn't produce clearly audible speech - the speech is distorted, not clear. Clear speech would indicate proper reception, not interference.

Exam Tip

SSB interference sound = distorted speech. Think 'S'SB 'I'nterference = 'S'peech 'I's distorted. SSB signals are demodulated by audio device's non-linear circuits, producing distorted audio. Not hum, not clicking, not clear speech - just distorted speech.

Memory Aid

Real-World Example

Your neighbor's SSB transmitter is interfering with your audio system. You hear distorted speech coming from your speakers - the SSB signal is being demodulated by the audio device's non-linear circuits, producing garbled, distorted audio. This is the characteristic sound of SSB interference.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G4C

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

Key Concepts

SSB interference Distorted speech Audio device RFI symptoms

Verified Content

Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G4C topic.