A very simple one transistor audio amplifier

 A very simple one transistor audio amplifier 

Introduction

Many a time a novice or an electronics budding enthusiast wants to build a very simple tiny audio amplifier with just one transistor along with a few passive components. Here is an interesting and a simple circuit of such a type which is capable of deliverying upto 100 mw audio power output. The circuit is easy to assemble and has utility value in small applications.

The three golden steps such as knowing your circuit, knowing your design and knowing your assembling are to be followed in constructing an electronic project for its optimum performance and utility and satisfaction. 

You can understand the need for this three steps approach is discussed here.

Know your circuit

The circuit schematic of the audio amplifier is given here. It contains a very few components and the design is very simple and straight forward. Input audio signal to be made loud is fed to the pin P1and passes on to the base of the transistor Q1 through 10MFD electrolytic capacitor. Q1 transistor gets base bias through R1, R2 resistor networks and through the voice coil of the speaker. The speaker SP1 is connected to the collector of Q1 and works as collector load. The emitter of Q1 is directly connected to the earth -ofcourse to the -ve potential of the battery. The C2 electrolytic capacitor as acts decoupling to the power supply. As such the design is very simple and easy to construct on any general purpose vero board.  

Parts list

Q1 = 2N2222 NPN transistor

R1 = 100K ohm resistor

R2 = 1K ohm resistor

C1 = 10MFD 10V electrolytic capacitor

C2 = 100 MFD 25V electrolytic capacitor

SP1 = Speaker 8 ohms 3W 

Know your design

The design is very simple and all details are discussed as above. This circuit can be used as an add on circuit whereever a mini audio amplifier circuit is required to be attached to get the audio signal boost. It is a simple and perfect match for handy design and ease of operation besides cost effective. Optimising the design assembly will be beneficial always. 

Know your  assembling

This is a very simple circuit and any body can construct without any skill for the use. AS the component count and circuit design is very tidy one can assemble it on a very small vero board for perfect add on as supplement circuit to the main circuit. It is fit to any place and pocket. 

Conclusion 

One can definitely construct this simple circuit in his job and enjoy the thrill of one transistor audio amplifier output . Comments are welcome on the readers views and opinions.