THE DESIGN AND CONSTRUCTION OF A 40 WATT HI-FI AMPLIFIER
Approval page
Dedication
Acknowledgement
Table of content
Introduction
Components Explanation
Capacitor
Value of a capacitor
Tolerance
Working voltage
Leakage current
Component and Operation of a Capacitor
Resistor
Printed Circuit Board
Loudspeaker
Cabinet Screen
Heat Sink
Variable Resistor
Integrated Circuit
Diode
Diagrams of project
Operation manual
Construction
Economic of the project
Reliability
Maintainability
Testing
Conclusion
Bibliography
High power amplifier are usually quite costly and usually beyond the easy reach of most audio enthusiastic (and Hi-Fi buffs) who then have to remain satisfied with those small 6 watt amplifiers. Well, with this introduction to us and to electronics, things should change. Well this low cost Hi-Fi amplifier that delivers ear chatting and thundering output of an unbelievable forty watts. The unique features of this circuit are.
vLow cost – The basic criteria
vCompact size
vVery low transient noise on “power on” and low THO
vEffective Bass and treble controls
vAutomatic thermal shut down system it switches off the amplifier in case of overheating
vLoad damp protection in built.
The circuit uses a high power amplifier chip viz the LA 4440. the circuit is quite self explanatory. The input is coupled by a small value capacitor. The output is taken through a block terminal and fed to the speaker.
Most electrical electronics components are made up of mechanical and electrical contacts, electromagnetic coils, protecting devices, switches and indicating devices for circuit operation, for this reason adequate precaution is needed when selecting or determining the components and the following points as to be considered.
vRating of the equipment to be controlled
vRating of the components parts
vThe operation voltage and current
vTemperature co-efficient of the components
vMode of operation
vReliability of the components
The 40 watt Hi-Fi amplifier components are described and it operational method and control.
The components are:
vCapacitor resistor
vPrinted circuit board
vLoudspeaker
vCabinet screw
vHeat sink
vVariables (volume control)/ variable resistor
vIntegrated circuit (IC LA 4440)
vDiode
CAPACITOR
A capacitor stores electric charge. Basically it consists of two metal plates separated by an insulator called the dielectric. When connected to a battery the capacitor charges up until the potential different between it’s terminals is the same as the e.m.f of the battery, if the battery is removed, the charge may take a long time to leak away unless a conductor is connected across the terminals.