Amplifiers

1. Amplifier is an electronic device used to increase the strength of the signal fed into it. As for preamplifier is a device typically used along with sound equipment to help improve the overall quality of sound.

2. Is a fundamental active element of analog circuit design. It is most commonly used in amplifier and analog signal processing circuits in the frequency band from 0 to 100 kHz.

3. The noise contribution of the amplifier's noise source is fixed and does not change with input signal. Therefore, when more noise is present at the amplifier input, the contribution of the internal noise source is less significant in comparison.

4. Voltage rate * Amp efficiency* Fuse rate.

5. Because class A valve is conducting current at all times.

6. The benefits of direct coupling are very good low frequency response, often from DC (if the input/output coupling capacitors are not used) to the highest operating frequency that the system will allow.

7. The benefits of resistance-capacitance are used as the input and output impedances of the circuits being coupled; a coupling capacitor is generally used between the resistors to transfer the signal from one stage to the next.

8. The function of an oscillator is to produce sustained oscillations without any ac input.it is nothing but an amplifier with positive feedback and without input.it just converts the noise in the circuit and amplifies it to produce oscillations.

9. A basic oscillator is a capacitor and inductor connected together. As the capacitor discharges, the current creates a magnetic field in the inductor. When the capacitor is fully discharged, the field collapses and induces an opposite current that charges the capacitor again. This cycle continues until all the energy is lost through resistance. The frequency of the oscillations depends on the size of the capacitor and inductor.

10. The Hartley oscillator has a tap between two coils, while the Colpitts has a tap between two...