SUMMER INTERNSHIP-2015

ALL INDIA RADIO (AIR)

________________________________

SDM COLLEGE OF ENGINEERING &TECHNOLOGY

DHARWAD-02

ELECTRICAL & ELECTRONICS DEPARTMENT

SUBMITTED BY : J KISHOR

USN : 2SD12EE021

Emial : Kishor.jayaram@gmail.com

Mob : 9742054779

SDM COLLEGE OF ENGINEERING &

TECHNOLOGY, DHARWAD-580002

DEPARTMENT OF ELECTRICAL AND

ELECTRONICS ENGINEERING

CERTIFICATE

This is to certify that the internship work carried out by J.KISHOR at ALL INDIA

RADIO (AIR) adds value for the degree of Bachelor of Engineering in Electrical and

Electronics Engineering of S.D.M. College of Engineering and Technology under VTU,

Belgaum during year 2015.

Ravi S.Honnalli Prof. G D Kamalapur Dr. S B Vanakudre

( Assistant Engineer (Head of Department) (Principal)

AIR )

ACKNOWLEGDGEMENT

The internship opportunity I had with ALL INDIA RADIO was a great chance for

learning and professional development. Therefore, I consider myself as a very lucky individual

as I was provided with an opportunity to be a part of it. I am also grateful for having a chance

to meet so many wonderful people and professionals who led me though this internship period.

Bearing in mind previous I am using this opportunity to express my deepest gratitude

and special thanks to Ravi S Honnalli who in spite of being extraordinarily busy with his duties,

took time out to hear and guide me.

Also I like to sincerely thank the staff of AIR, Dharwad for their kind help and support

in every phase of our internship.

I would also like to sincerely thank our beloved H.O.D Prof. G D Kamalapur, Electrical

and Electronics Department, SDMCET Dharwad for his support and encouragement.

I perceive as this opportunity as a big milestone in my career development. I will strive

to use gained skills and knowledge in the best possible way, and I will continue to work on

their improvement, in order to attain desired career objectives.

J Kishor

CONTENTS

1. INTRODUCTION

1.1 TYPES OF COMMUNICATION

1.2 SPECTRUM

1.3 TECHNOLOGIES USED IN DIFFERENT COUNTRIES

1.4 SIGNAL MODULATION TECHNIQUES

2. EQUIPMENTS IN AIR

2.1 MICROPHONES

2.2 STUDIO

2.3 SOFTWARES

2.4 AM TRANSMITER

2.5 FM TRANSMITTER

2.6 ANTENNAS

3. SATELLITE BROADCASTING

4. MICROWAVE COMMUNICATIONS

5. SWITCHGEARS

6. POWERSUPPLY

7. POWER DISTRIBUTION

8. BACKUP POWERSUPPLY

INTRODUCTION

SACFA (Standing Advisory Committee of Frequency Allocation)

ITU (International Telecommunication Union)

CCIR (Consultative Committee for International Radio)

The above are the international institutions meant for communication, any broadcasters have

to satisfy their rules in order to get permission for the broadcast of their respective programme.

They will be allotted with particular frequency band and continuously monitored ensuring no

overlapping with the other allotted bands.

ABOUT ALL INDIA RADIO (AIR)

AIR is allotted with 1140MHz

It is the National public broadcaster

Doddaballapur is the biggest shortwave transmission station in Asia

99% of India’s population is covered by AIR

Around 500 Transmitters

Major stations: Bangalore &

Dharwad: 2 transmitter of 100KW each covering 10-12 district (uttara Karnataka)

By 2017 Analog communication will be replaced by Digital communication.

EQUIPMENTS

1. MICROPHONE

TYPES: Dynamic, Ribbon , Electrostatic/Condenser ,

FEATURES

CHARACTERICTICS: Free response, Directivity, Sensitivity.

FIELD USAGE

2. STUDIO

Acoustic Treatment: Propagation of Sound Waves, Reverberation time, Acoustic observers

TYPES: Drama, Talk, Music, Playback, Vivid Bharathi, control room

Console

MODULATION

Types of Modulation

In general, there are three types of modulation:

a) Amplitude Modulation b) Angle Modulation c) Pulse Modulation

Amplitude Modulation

If the amplitude of the carrier is varied in accordance with the amplitude of the

modulating signal (information), it is called amplitude modulation. This modulation has

been shown in figure 1. We can see this on the screen of oscilloscope.

If the frequency of the carrier is varied in accordance with the amplitude of the

modulating signal (information), it is called frequency modulation. This has been

shown in figure 9.

FM TRANSMITTER

FM Exciter

Power amplifiers Antenna

SATELLITE COMMUNICATION:

Satellite Transponder

As shown in above figure, the uplinked signal (6 GHz) at satellite is received, amplified

and down converted to 4 GHz band and sent back through filter and power amplifier

(TWT). The local oscillator frequency of down converter is 2225 MHz for C band and

Ex-C band transponders.

POWER CONSUMPTION

125KVA By Studio

450 KVA By Transmitters

On an average AIR Dharwad pays 10Lakh per month for Power

They have power factor corrective measures to ensure unity power factor throughout

the time.

POWER BACKUP

AIR Dharwad has one 6.2KVA diesel generator

HT VCB PANELS

Capacity: 11KV, 250MVA, 200A

Insulation: 28KV

PT RATIO: 11KV/110KV CT RATIO: 25/5.5

LT PANEL

HT TRANSFORMER

CAPACITY: 250KVA, 11KV/433V

HV CURRENT: 13.12A LV CURRENT: 333.3A

CONCLUSION

Overall I had a fascinating experience. I feel extremely fortunate that I had this opportunity.

The internship at AIR provided interesting insight of Radio Studios and Broadcasting

equipment, Hard Disk Based Recording, Live broadcasting, Modulation/Demodulation

Techniques, FM/AM Transmitters and Satellite Broadcasting.