🔍 Key Concepts

• Single-sideband (SSB) voice signals and their typical audio frequency range • How a band-pass filter bandwidth relates to the desired audio quality and suppression of unwanted sidebands • Typical SSB filter widths used in HF marine and amateur radios

💭 Think About

• Think about the normal range of human speech frequencies that need to pass through for clear voice communications. • Consider which bandwidths are too narrow and would cut off important speech components, and which are so wide that they admit unnecessary noise and adjacent-channel interference. • Compare each option to what you would expect for a standard SSB voice filter in commercial/marine or amateur transceivers.

✅ Before You Answer

• Estimate the usable voice frequency range (in Hz) needed for understandable speech over radio. • Check which answer choices are clearly too wide for a single voice signal, more like multiple channels or wideband audio. • Check which answer choices are so narrow that they would sound muffled or distorted for normal voice.