What does the oscillator in a radio transmitter do?

What does the oscillator in a radio transmitter do?

• A. Generates audio modulation
• B. Provides DC power
• C. Creates alternating current at the transmitter frequency
• D. Mixes signals for downconversion

Answer: (C)

The oscillator’s job is to generate a stable RF carrier at the transmitter’s operating frequency. It produces a sinusoidal alternating current whose frequency matches the carrier, and this carrier is then modulated by the audio signal and sent through the RF chain to the antenna. It doesn’t provide DC power—that comes from the power supply. It also doesn’t mix or downconvert signals—that’s done by a mixer stage elsewhere. So, the oscillator’s role is to create the alternating current at the transmitter frequency, providing the carrier that carries the modulated information.

The oscillator’s job is to generate a stable RF carrier at the transmitter’s operating frequency. It produces a sinusoidal alternating current whose frequency matches the carrier, and this carrier is then modulated by the audio signal and sent through the RF chain to the antenna. It doesn’t provide DC power—that comes from the power supply. It also doesn’t mix or downconvert signals—that’s done by a mixer stage elsewhere. So, the oscillator’s role is to create the alternating current at the transmitter frequency, providing the carrier that carries the modulated information.