Question

The frequency of an FM transmitter without signal input is:

• A. the center frequency
• B. modulation
• C. the frequency deviation
• D. the carrier swing

Hint:

The frequency of an FM transmitter without a signal input is its center frequency, and modulation occurs when a signal is present.

Answer 1

The Correct Option is A

Step 1: Definition of FM transmitter frequency.
The frequency of an FM transmitter without a signal input is the carrier frequency, which is the central frequency of the transmission.
Step 2: Explanation.
When there is no input signal, the transmitter operates at the center frequency, and modulation or frequency deviation occurs only when the signal is applied.
Final Answer: \[ \boxed{\text{A) the center frequency}} \]