ABSTRACT

The purpose this text is to present at a primary and intermediate level a comprehensive over view of the construction principles and indeed the operation of a power amplifier with 100w as the output power.
The history and importance of electronic as a unique braches of science cannot be over emphasized electronic as its history might have it is divide into sections the first began with the invention of the vacuum tube the second occupying the later half of twentieth century is based on the invention of the transistor and semi conductors.
Since electronic is the branch of science and technology rating to the conduction and control of electricity flowing through semi-conductors materials or through vacuum are gazed. It’s applications to industry with be concerned with the design manufacture and application of transistor diode integrated circuit and other semi conductors devices and to a much lesser extent vacuum tubes.
Therefore it is a fact crystal clear that it is from the above breed and follow up form the electronic industry that such devices like the power amplifier was a able to be made.
Power transistor amplifier are therefore device or amplifier design to produce high power required to drive a current operated load the load usually is a transducer that convents electrical energy to some other form of energy the transducer may be a load speaker in an circuit.
It is commendable to note here that with help of this master price of work on construction and operation of power amplifier, students of electronic department now have a text to lay their hands.

CHAPTER ONE

INTRODUCTION 
Power amplifier is an electronic device which is used to increase sound energy. In other words the final stage which must drive a given load such as mechanical inductor loudspeaker cathode by tube a transmitter aerial of a communication network it is equally used to regulate power supplies.
In power amplifier a large portion of the active device (transistor) characteristics used that is there is large alternating in put voltage or current to make efficient use of the device.
The economic importance of power amplifier is known to useful in many aspect of both social and business activities in public address system power amplifier is very essential for amplification of signals from microphone to be heard by listeners.
The system employs a pre-amp—stage that amplifier very low level output signal from a microphone too little for power amplifier. The power amplifier thus increase the signal level significantly to the level that operates the speakers.
One of the most important requirements fro an amplifier is that it is reliable for if an amplifier breaks down in the middle of on concert. It can cause all sort of repercussion so reliability is very high on the list for this reasons the power transistors are one of the best choice for the input level. Hence they do not easily suffer from thermal runway as they deliver maximum power.
One of the feature of this amplifier is that the harmonic distortions is 0.01% electronic decoupling is used inn the supplier the stages of the power-amp and these enables very how distortion to be maintained all power out put as well as improving the overall signal to noise ratio.
The circuit also incorporates tone control, which enables the listener to alter the tonal quality (that is frequency responses) of the sound being produced.