🔍 Key Concepts

• Pre-emphasis / de-emphasis in FM: why we shape the audio spectrum before and after transmission • Which part of the audio band (high vs low frequencies) is more affected by noise in FM systems • Typical slope used in FM pre-emphasis networks (dB per octave)

💭 Think About

• Think about which audio frequencies are more easily masked by noise in an FM signal: are the higher or lower audio frequencies more vulnerable? • In an FM transceiver pair, whatever you boost before transmission must be reduced by the same amount at the receiver. Which option shows a consistent pre-emphasis / de-emphasis pair? • Recall the standard pre-emphasis characteristic used in common FM systems: is it usually 3 dB/octave or 6 dB/octave?

✅ Before You Answer

• Make sure the choice you pick boosts the same band (high or low) that is then reduced at the receiver — they must match. • Confirm whether FM pre-emphasis is meant to help the part of the signal that suffers most from noise (typically at higher audio frequencies). • Verify the typical FM pre-emphasis slope used in standard systems (hint: it corresponds to a common time constant like 50 µs or 75 µs).