Design And Construction Of A Multipurpose Listening Device

ABSTRACT

This multipurpose listening device can detect very faint, remote sounds with a good clarity. It is useful in large conference halls, auditoria, cinema halls, lecture rooms in colleges, etc. The circuit can be housed in a small plastic box and kept in a shirt pocket. It is especially useful for watching TV programs at a low volume so as not to disturb other family members in the house.

An electric microphone is used to pick up sounds. The advantages of using it are its excellent frequency range and high sensitivity. Four transistors and a few resistors and capacitors are required for fabricating the circuit.

TABLE OF CONTENTS

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

1.0      INTRODUCTION

1.1      BACKGROUND OF THE PROJECT
1.2      AIM OF THE PROJECT
1.3      OBJECTIVE OF THE PROJECT
1.4      SIGNIFICANCE OF THE PROJECT
1.5      PURPOSE OF THE PROJECT
1.6      APPLICATION OF THE PROJECT
1.7      ADVANTAGES OF THE PROJECT
1.8      PROBLEM/LIMITATION OF THE PROJECT
1.9      PROJECT ORGANISATION

CHAPTER TWO

2.0     LITERATURE REVIEW

2.1      OVERVIEW OF THE STUDY

2.2      USES OF THE STUDY

2.3     REVIEW OF CANDIDACY AND ACQUISITION OF THE STUDY

2.4     REVIEW OF DIFFERENT TYPES OF MULTIPURPOSE LISTENING DEVICES

2.5      HISTORICAL BACKGROUND OF MULTIPURPOSE LISTENING DEVICE

CHAPTER THREE

3.0     METHODOLOGY

3.1      BLOCK DIAGRAM

3.2     SYSTEM OPERATION AND DESCRIPTION

3.3     SYSTEM CIRCUIT DIAGRAM

3.5     DESCRIPTION AND FUNCTION OF THE MAJOR COMPONENTS USED IN THIS CIRCUIT

CHAPTER FOUR

RESULT ANALYSIS

4.0      CONSTRUCTION PROCEDURE AND TESTING

4.1      CASING AND PACKAGING

4.2      ASSEMBLING OF SECTIONS

4.3      TESTING

4.4.1 PRE-IMPLEMENTATION TESTING

4.4.2 POST-IMPLEMENTATION TESTING

4.5      RESULT

4.6     COST ANALYSIS

4.7      PROBLEM ENCOUNTERED

CHAPTER FIVE

5.1      CONCLUSION

5.2      RECOMMENDATION

5.3      REFERENCE

CHAPTER ONE

1.0                                                       INTRODUCTION

1.1                                           BACKGROUND TO THE STUDY

Hearing is one of the five senses along with vision, taste, smell and touch. The ear serves as a receiver of incoming sounds. Although the ear receives sound and is the sense organ for hearing, it is the brain and central nervous system that interpret the sound. The human auditory system can generally hear sounds within the frequency range of 20 Hz and 20 kHz but the frequency range between 100Hz and 6 kHz contains most of the information of human voice (Sergei Kochkin, 2015). Although the sensation of hearing requires an intact and functioning auditory portion of the central nervous system as well as working ear, human deafness (extreme insensitivity to sound) and hearing loss most commonly occur because of damages of the ear, rather than the central auditory system.

A multipurpose listening device is a small device used for amplifying low audio signal. This multipurpose listening device can detect very faint, remote sounds with a good clarity.

The basic components of a multipurpose listening device are a microphone, transistors – for amplification, a headphone, and 3v battery. The microphone converts the sound into an electric signal. The signal then undergoes conditioning that can be as simple as amplifying all of the sound equally, to more advanced equalization involving a digital signal processor. The headphone receives the output, and the battery powers the electronics (Schum, D.J. 2004).

1.2                                   OBJECTIVE OF THE PROJECT

The objective of this work is to design an electro-acoustic device which amplifies sound for the wearer, usually with the aim of making speech more intelligible, and audible.

1.3                                   SIGNIFICANCE OF THE PROJECT

Hearing aids are incapable of truly correcting a hearing loss; they are an aid to make sounds more accessible. The circuit can be housed in a small plastic box and kept in a shirt pocket. It is especially useful for watching TV programs at a low volume so as not to disturb other family members in the house.

1.4                                  SCOPE OF THE PROJECT

Multipurpose listening device help people who have hearing loss. This multipurpose listening device circuit works using four transistors and several passive electronic components.

1.5                              LIMITATION OF THE PROJECT

Some multipurpose listening device comes with non-replaceable battery which can only be dispose when the battery dies, this means that multipurpose listening device with non-replaceable battery can be costly than the one that has replaceable battery because if the battery dies one have to dispose it. Multipurpose listening device can be noisy when the battery gets low.

1.6                                   APPLICATION OF THE PROJECT

It is useful in large conference halls, auditoria, cinema halls, lecture rooms in colleges, etc.

1.7                                         METHODOLOGY

To achieve the aim and objectives of this work, the following are the steps involved:

1. Study of the previous work on the project so as to improve it efficiency.
2. Draw a block diagram.

• Test for continuity of components and devices,

1. Design and calculation for the device was carried out.
2. Studying of various component used in circuit.
3. Construction of the circuit was carried out.

• Finally, the whole device was cased and final test was carried out.

1.8                               PROJECT WORK ORGANISATION

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this work is on the introduction to this work. In this chapter, the background, significance, objective limitation and problem of this work were discussed.

Chapter two is on literature review of this work. In this chapter, all the literature pertaining to this work was reviewed.

Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.

Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.

Chapter five is on conclusion, recommendation and references.