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How does the amplification work?
An amplifier takes an input signal from a source, such as a laptop, turntable or CD player, and creates a larger copy of the original signal before it’s sent to the speakers. It gets the power to do this from your mains electricity, which is sent directly to the power supply within the amplifier.
What is amplification principle?
The power amplifier works on the basic principle of converting the DC power drawn from the power supply into an AC voltage signal delivered to the load. Although the amplification is high the efficiency of the conversion from the DC power supply input to the AC voltage signal output is usually poor.
How does an amplification circuit work in a transistor?
The emitter to base circuit forms the input side of the amplifier while the collector to base circuit forms the output side. The signal voltage V S to be amplified is applied at the input side. A load resistor R L is connected in the output circuit and the amplified output voltage is developed across R L.
How is the action of a transistor biased?
In figure 1, the transistor is biased for active region operation i.e. J E is forward biased using voltage source V EE and J C is reverse biased using voltage source V CC. The emitter to base circuit forms the input side of the amplifier while the collector to base circuit forms the output side.
How is the base emitter junction in a transistor?
The base-emitter junction is forward biased and allows low resistance for the emitter circuit. The base-collector junction is reverse biased and provides high resistance in the collector circuit. Before discussing transistor action, it is important to keep in mind the following facts about the transistor:
How is the load collected in a transistor?
The load is connected at the collector of a transistor and for a single-stage amplifier, the output voltage is taken from the collector of the transistor and for a multi-stage amplifier, the same is collected from a cascaded stages of transistor circuit. By definition, it is the total load as seen by the a.c. collector current.