A demodulator circuit contains

Options

A. A diode
B. A transistor
C. A solar cell
D. Logic gate

Answer

### Step-by-Step Solution:

1. **Understanding Demodulation**:
- Demodulation is the process of extracting the original information-bearing signal from a modulated carrier wave. It is the reverse operation of modulation.

2. **Components of a Demodulator Circuit**:
- A typical demodulator circuit consists of several components, but the essential ones include:
- **Diode**: Used to rectify the received modulated signal.
- **Capacitor**: Used to smooth out the rectified signal and help recover the original signal.

3. **Function of the Diode**:
- The diode allows current to flow in one direction only, which helps in rectifying the modulated signal. This means it converts the alternating current (AC) signal into a direct current (DC) signal.

4. **Function of the Capacitor**:
- The capacitor stores the charge and helps in filtering the rectified signal. It smoothens the output by reducing the ripple in the signal, thus allowing the recovery of the original signal.

5. **Conclusion**:
- Therefore, a demodulator circuit primarily contains a diode and a capacitor to regain the original signal from the modulated carrier wave.

### Final Answer:
A demodulator circuit contains a diode and a capacitor.

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