What is the stage in a VHF FM transmitter that generates a harmonic of a lower frequency signal to reach the desired operating frequency?
Why A frequency multiplier is a stage deliberately driven into nonlinearity so its output is rich in harmonics, and a tuned circuit at the output selects the desired harmonic (2x, 3x, etc.) of the input. Classic VHF FM transmitters generate the signal at a low frequency where a crystal oscillator and reactance modulator work well, then multiply up to the operating frequency. A useful side effect is that the frequency deviation is multiplied by the same factor, so a small deviation at the oscillator becomes the full 5 kHz deviation on the air.
Watch out A mixer is the tempting pick, but mixing combines two different input frequencies to produce sum and difference products, not a harmonic of a single input. A reactance modulator is what applies the FM in the first place.
Multiplier = multiply the frequency (and the deviation) by a whole number; mixer needs two inputs, multiplier needs one.