🔍 Key Concepts

• Harmonic radiation in radio transmitters and antennas • The meaning of whole-number multiples of a fundamental frequency (2f, 3f, 4f, etc.) • How proper tuning and filtering affect unwanted emissions

💭 Think About

• Look at each choice and ask: does this describe a defining property of harmonic radiation, or just something that may be true in some cases? • Consider the relationship between a harmonic and the fundamental frequency: can a harmonic ever be lower than the fundamental? • Think about why regulations limit spurious and harmonic emissions: what role do transmitter tuning and filters play in controlling them?

✅ Before You Answer

• Verify whether harmonics are always higher than the fundamental, or if that word "always" might be a trap. • Check if harmonic radiation is by definition at integer (whole-number) multiples of a fundamental frequency. • Decide whether transmitter tuning directly reduces harmonics or whether it mainly affects the power at the fundamental frequency and uses filters for harmonics.