🔍 Key Concepts

• Frequency modulation (FM) basics: how carrier frequency changes with the audio signal • Difference between deviation (how far the carrier moves) and modulation (the process itself) • Specific definition: maximum frequency deviation divided by maximum modulating frequency

💭 Think About

• Ask yourself: When we talk about a ratio involving maximum deviation and maximum modulating frequency, is that normally tied to the word 'deviation' or 'modulation'? • Consider what the word index vs ratio usually means in communications theory. Which term is traditionally used for deviation over modulating frequency in FM? • Think about what quantity helps describe how 'wide' the FM signal swings compared with how fast the audio changes. Which of the options is defined this way?

✅ Before You Answer

• Verify which term in radio theory is defined as (maximum frequency deviation) / (maximum modulating frequency). • Check standard radio communications references for the definition of FM modulation index and compare it to deviation ratio. • Be sure you distinguish between terms that describe the process of modulation and those that describe a numerical ratio of deviation to modulating frequency.