A repeater is a combination of

Options

A. Receiver
B. Amplifier
C. Transmitter
D. All of these

Answer

To answer the question "A repeater is a combination of," we can break it down into the following steps:

### Step-by-Step Solution:

1. **Definition of a Repeater**:
- A repeater is a device used in communication systems to receive, amplify, and retransmit signals. It helps in extending the range of communication by overcoming signal loss due to attenuation.

2. **Components of a Repeater**:
- **Receiver**: The repeater must have a receiver to capture the incoming signal. This component is essential for detecting the signal that needs to be amplified and retransmitted.
- **Amplifier**: The signal often loses strength as it travels over distances. The amplifier is crucial in the repeater to boost the strength of the received signal, ensuring that it can be effectively retransmitted.
- **Transmitter**: After amplifying the signal, the repeater needs a transmitter to send the strengthened signal to the next stage in the communication system.

3. **Functionality of a Repeater**:
- The repeater receives the weak signal, amplifies it using the amplifier, and then retransmits the amplified signal through the transmitter. This process allows the signal to travel longer distances without significant loss of quality.

4. **Conclusion**:
- Therefore, a repeater is a combination of a receiver, an amplifier, and a transmitter.

### Final Answer:
A repeater is a combination of a receiver, an amplifier, and a transmitter.

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