Design And Construction Of A 30Km Range FM Transmitter Using Discrete Components

Overview

ABSTRACT

An FM transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves.

FM transmitter is basically a VHF colipits oscillator capable of transmitting sound or music to any standard FM receiver. The circuit works on a D.C source which makes it for a pure rectification. FM transmitter also has a capacitor microphone which picks up very weak sound signals, and discrete components such as: Transistor, Diode, Resistor, Capacitor and Inductor.

The distant of transmission is limited to 30km and fixed frequency of transmission, away from all other radio station. This gives best range and least interference.

 TABLE OF CONTENTS

TABLE OF CONTENT

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

1.0 INTRODUCTION

1.1 PURPOSE OF THE PROJECT

1.2 OBJECTIVE OF THE PROJECT

1.3 LIMITATIONS OF THE PROJECT

1.4      SCOPE OF THE PROJECT

CHAPTER TWO

2.0 LITERATURE REVIEW

2.1 HISTORITICAL BACKGROUND OF THE PROJECT

2.2 REVIEW OF PARTS OF RADIO TRANSMITTER

2.3 REVIEW OF FM BROADCAST BANDS

2.4 MODULATION AND DEMODULATION

2.5 PER-EMPHASIS AND DE-EMPHASIS

2.6 REVIEW OF MODULATION CHARACTERISTICS

CHAPTER THREE

3.0 CONSTRUCTION

3.1 BASICS OF FM TRANSMITTER

3.2 BLOCK DIAGRAM OF AN FM TRANSMITTER

3.3 FUNCTION OF FM TRANSMITTER BLOCK

3.4 CIRCUIT DIAGRAM OF THE SYSTEM

3.5 CIRCUIT PARTS

3.6 CIRCUIT OPERATION

3.7 DESCRIPTION OF COMPONENTS USED

CHAPTER FOUR

4.0 RESULT ANALYSIS

4.1 CONSTRUCTION PROCEDURE AND TESTING

4.2 CASING AND PACKAGING

4.3 ASSEMBLING OF SECTIONS

4.4 TESTING OF SYSTEM OPERATION

4.5 INSTALLATION OF THE COMPLETED DESIGN

4.6 SYSTEM TROUBLESHOOTING METHOD

4.7 COST ANALYSIS

CHAPTER FIVE

5.0 CONCLUSION

5.1 RECOMMENDATION

5.2 BIBLIOGRAPHY

CHAPTER ONE

1.0                                                        INTRODUCTION

In electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves. In addition to their use in broadcasting, transmitters are necessary component parts of many electronic devices that communicate by radio, such as cell phones, wireless computer networks, Bluetooth enabled devices, garage door openers, two-way radios in aircraft, ships, and spacecraft, radar sets, and navigational beacons. The term transmitter is usually limited to equipment that generates radio waves for communication purposes; or radiolocation, such as radar and navigational transmitters. Generators of radio waves for heating or industrial purposes, such as microwave ovens or diathermy equipment, are not usually called transmitters even though they often have similar circuits.

The term is popularly used more specifically to refer to a broadcast transmitter, a transmitter used in broadcasting, as in FM radio transmitter. This usage usually includes the transmitter proper, the antenna, and often the building it is housed in.

A transmitter can be a separate piece of electronic equipment, or an electrical circuit within another electronic device. A transmitter and receiver combined in one unit is called a transceiver. The term transmitter is often abbreviated “XMTR” or “TX” in technical documents. The purpose of most transmitters is radio communication of information over a distance. The information is provided to the transmitter in the form of an electronic signal, such as an audio (sound) signal from a microphone. The transmitter combines the information signal to be carried with the radio frequency signal which generates the radio waves, which is often called the carrier. This process is called modulation. The information can be added to the carrier in several different ways, in different types of transmitter.

In a frequency modulation (FM) transmitter, it is added by varying the radio signal’s frequency slightly. Many other types of modulation are used.

The antenna may be enclosed inside the case or attached to the outside of the transmitter, as in portable devices such as cell phones, walkie-talkies, and garage door openers. In more powerful transmitters, the antenna may be located on top of a building or on a separate tower, and connected to the transmitter by a feed line, that is a transmission line.

1.1                                              PURPOSE OF THE PROJECT

The main purpose of this work is to construct a device that will allow music or other audio content from a portable media player, CD player or other portable audio system to be played through a nearby FM radio. It can either be a capability built into a portable media player, or a portable appliance that plugs into the headphone jack or proprietary output port of a portable media player or video device. The sound is then broadcast through the transmitter on an FM broadcast band frequency and picked up by the receiver. The purpose is generally to allow portable audio devices to make use of the better sound quality of a home audio system or car stereo without requiring a wired connection between them.

The FM transmitter plugs into the audio output of audio devices and converts the audio output into an FM radio signal, which can then be picked up by appliances such as car or portable radios.

1.2                                             OBJECTIVE OF THE PROJECT

The objective of this work is to design and construct an FM transmitter which transmits a frequency modulated signal to an fm radio. That is, to construct a device that can broadcast signals on an FM broadcast band and picked up by the receiver. The distant of transmission is limited to 30km and fixed frequency of transmission, away from all other radio station. This gives best range and least interference.

1.3                                          LIMITATIONS OF THE PROJECT

  • Discrete components such as: Transistor, Diode, Resistor, Capacitor and Inductor are only used in this work.
  • The distant of transmission is limited to 30km and fixed frequency of transmission, away from all other radio station. This gives best range and least interference.

 1.4                                                  SCOPE OF THE PROJECT

FM transmitter is basically a VHF colipits oscillator capable of transmitting sound or music to any standard FM receiver. The circuit works on a D.C source which makes it for a pure rectification. FM transmitter also has a capacitor microphone which picks up very weak sound signals, and discrete components such as: Transistor, Diode, Resistor, Capacitor and Inductor.

This project transmits frequency on 100MHz± 5%. The transmitting distance is l00metres. It is powered with 5volt – 15volts D.C battery using suitable F.M receiver tuned to the transmitting frequency of this project. F.M Transmitter can be used as cordless microphones, mobile phone and for public address purposes.

Research Guidelines

The Title Page should be the first section of your project “Design And Construction Of A 30Km Range FM Transmitter Using Discrete Components”, providing essential details like the project title, your name, your supervisor’s name, the institution, and the submission date. After that, the Abstract offers a brief summary of your project, touching on its purpose, methods, results, and conclusions in 150-300 words. The Acknowledgments section is where you can thank those who supported your research, such as your supervisor, peers, or organizations that provided resources.

Next, the Table of Contents organizes the Design And Construction Of A 30Km Range FM Transmitter Using Discrete Components by listing its chapters and sections, along with page numbers for easy reference. The List of Figures and List of Tables help guide readers to specific visual elements like graphs, charts, or tables included in the document. There should also be an Abbreviations and Glossary section to explain any specialized terms or acronyms, making the content clearer to readers unfamiliar with the technical language.

The main body of the Design And Construction Of A 30Km Range FM Transmitter Using Discrete Components should start with the Introduction, which provides background information, outlines the research problem, states your objectives, and gives a brief overview of your research methods. Following that, the Literature Review offers an in-depth look at previous research relevant to your project, identifying gaps your study aims to address. The Methodology section then explains the research design, tools, and data collection methods you used to conduct the project and analyze the data.

In the Results and Discussion section, you present your findings and discuss them in relation to the Design And Construction Of A 30Km Range FM Transmitter Using Discrete Components research questions or objectives, often using tables or charts to help explain the data. The Conclusion summarizes the key results, discusses their implications, and suggests possible directions for future research. You may also include recommendations based on your findings, offering practical advice for improvements or applications. Finally, the Design And Construction Of A 30Km Range FM Transmitter Using Discrete Components project should include a References or Bibliography section to list all the sources you cited, as well as Appendices for any additional material. A Statement of Originality is often included to confirm the authenticity of your work