*Question G4B08:
What transmitter performance parameter does a two-tone test analyze?*  

*Correct Answer is  A: Linearity*  

### AI Response: (may contain errors)  

A two-tone test is a method used to analyze the linearity of a transmitter, particularly in amplitude modulation (AM) and single sideband (SSB) systems. Here's why the correct answer is "Linearity" and why the other choices are incorrect:

1. **Correct Answer: Linearity**
   - **Explanation**: A two-tone test involves injecting two non-harmonically related audio frequencies into the transmitter. The purpose is to observe how well the transmitter can handle multiple signals without distortion. In a perfectly linear system, the output should only contain the original tones and their sum and difference frequencies. Any additional frequencies (intermodulation products) indicate non-linearity. This test is crucial for ensuring that the transmitter does not produce unwanted spurious emissions that can interfere with other communications.

2. **Incorrect Choices**:
   - **B: Percentage of suppression of the carrier and undesired sideband for SSB**
     - **Explanation**: This choice relates to the effectiveness of a transmitter in suppressing the carrier and the unwanted sideband in SSB transmission. It is not directly related to the linearity of the transmitter, which is what the two-tone test evaluates.
   - **C: Percentage of frequency modulation**
     - **Explanation**: This choice pertains to frequency modulation (FM) systems and measures how much the carrier frequency is varied by the modulating signal. The two-tone test is not used to analyze frequency modulation characteristics.
   - **D: Percentage of carrier phase shift**
     - **Explanation**: This choice involves the phase characteristics of the carrier signal, which is not what the two-tone test is designed to measure. The test focuses on amplitude linearity rather than phase characteristics.

In summary, the two-tone test is specifically designed to assess the linearity of a transmitter by checking for intermodulation distortion, making "Linearity" the correct answer.