Presentation on Industrial training

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PRESENTATION ON

INPLANT TRAINING

Presented by

Reshmi R

Reg. No. 80421

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CONTENTSSECTION – I

DDK

o HISTORYo INTRODUCTIONo STUDIO CHAINo STUDIOo PCRo MSRo DESo TRANSMITTERo OB VAN & DSNGo DTH

SECTION – IIAIR

o HISTORYo INTRODUCTIONo RADIO o STUDIO CHAINo STUDIOo CONTROL ROOMo STLo EARTH STATIONo TRANSMITTERS

CONCLUSION

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SECTION- IDDK

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HISTORY

o Doordarshan (DD) is an Indian public service broadcaster run by

Prasar Bharati.

o First service started on 15th Sept. 1959.

o TV services were separated from AIR in 1979.

o In 1982, Doordarshan Kendra (DDK) as a national broadcaster

came into existence.

o DDK Thiruvananthapuram was inaugurated on 1st January 1985.

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INTRODUCTION

o Doordarshan is India’s national TV channel.

o DD has over 1500 transmitters and is one of the largest

broadcasting organizations in the world.

o DDK Thiruvananthapuram is a part of the DD India.

o DDK Thiruvananthapuram is equipped with 2 studios, 2 terrestrial

transmitters & 1 digital up-link station.

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STUDIO CHAIN

Studio PCR MSR DES Transmitter

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STUDIO

o Studio is an arrangement in which production of programs take place.

o There are two studios in DDK

Small studio - for news production

Large studio - main studio

o Main components of a studio

TV Camera

Lighting

Microphone

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1. Camera

o Studio TV camera is the beginning of the video signal.

o A typical video camera consists of the following sections :

a) A Camera lens and optics : To form optical image on the

face plate of a pick up device.

b) A transducer or pick up device : To convert optical image

into an electrical signal.

c) Electronics : To process output of a transducer to get a

CCVS signal.

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2. Lighting

o Reasons for lighting: Artificial set to look like natural.

o TV Studio uses 3 point lighting.

1) Key light: Main light used to highlight any object.

2) Fill light: Used to suppress the shadow made by key light.

3) Back light: Used to separate artist from the background.

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3. Microphone

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PRODUCTION CONTROL ROOM (PCR)

o The overall control of a program

is done in production control

room by the producer.

o Has control consoles of :

Camera Control Unit (CCU)

Audio Mixer (AM)

Video Tape Recorder (VTR)

Vision mixer (VM)

number of displays, etc.

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PCR (Contd…)

o CCU : Controls aperture, optical focus, zoom of the lens system etc.

o AM : Combining, routing, and changing the level, timbre of audio signals.

o VTR : All the programs shot in the camera are simultaneously recorded

and playbacks the videos as and when required.

o VM : Enables the producer to select the desired sources or a combination

of the sources to compose the program. 3 types of switching or transitions

between various sources takes place in VM: Mixing Wiping Keying

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MASTER SWITCHING ROOM (MSR)

o Most of the switching electronics is

kept in MSR.

o Electronic equipment in MSR :

Camera base stations

Switcher main frame

Sync Pulse Generator (SPG)

Satellite receivers and

MW link.

o Signal is routed through MSR and can

be monitored at various stages in

MSR.

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DIGITAL EARTH STATION (DES)

o Earth Station is the unit from where programme signal is sent to the

satellite (uplink) and Programme signal transmitted by the satellite is

received at the earth station (downlink).

o Satellite: INSAT 3A

o Uplink frequency: 6036.5 MHz ( C band)

o Downlink frequency: 3811.5 MHz (S band)

o The whole system operates with DVB-T/MPEG2 standard for

terrestrial transmission.

o Systems operate in redundant mode and takes over in the event of

failure of the main chain.

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DES (Contd…)

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TRANSMITTER

A radio transmitter transforms electric power in to alternating current

radiating off a conductor as em waves.

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OB VAN & DSNG

o OB Van is used for live broadcasting.

o Divided into 4 parts: Production area or sitting area for all directors &

producers. Audio section Video section. Transmission where the signal is for quality control

purposes & transmitted or sent to other trucks.

o If there is a live program to be telecast following options can be

chosen: Microwave link DSNG (digital satellite news gathering) : Used for direct

uplinking or transmission to MSR.

o OB van is known as the mobile studio and the DSNG van as the mobile

earth station.

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OB VAN & DSNG (Contd…)

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DIRECT-TO-HOME (DTH)

o DTH or Direct Satellite Broadcasting (DBS) is the distribution of

television signals from high powered geo-stationary satellites to a small

dish antenna and satellite receivers at home.

o DTH services are fully digital, so it can offer value added services.

o It is the only free-to-air satellite television service in India.

o Insat 4B satellite is used to broadcast 64 FTA mpeg-2 channels and 24

mpeg-4 channels in Ku-Band.

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SECTION- IIAIR

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HISTORY

oAIR is the India’s national broadcaster established in 1930.

o It is one of the largest radio networks in the world.

o It is officially known as Akashvani.

o AIR’s motto is ” Bahujan Hitaya : Bahujan Sukhaya ”.

o AIR today has a network of 149 MW, 54 SW and 177 FM

transmitters.

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INTRODUCTION

o Radio is a powerful mass medium used in imparting information and

giving entertainment.

o AIR has a three-tier system of broadcasting.

National

Regional

Local

o The principal ingredients of AIR's programme output are music, talks,

interviews and discussions, newscasts, plays, features and

documentaries, educational broadcasts, outside broadcasts etc.

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RADIO

o Sound is transformed into an electrical signal which is applied to a transmitter.

o Transmitter sends the information through space on a radio wave.

o A receiver intercepts radio wave and extracts the electronic signal and converts

it back to original form by a speaker

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STUDIO CHAIN

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STUDIO

o Requires electronic equipment to generate programs.

o AIR Thiruvananthapuram has 7 studios. They are:

a) Recording studios:

i. Talk studio: recording of programs like interview.

ii. Drama studio

iii. Music studio: Light music studio & classical music studio.

b) Playback studios:

i. PB1 for Regional channel (MW)

ii. PB2 for IGNOU and NEWS

iii. PB3 for Ananthapuri FM

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Functions of studio

1) Recording:

Electrical or mechanical inscription of sound waves.

2) Editing: Recorded audio signals are edited by using editing software

(Sony Sound forge ).

3) Scheduling: Edited audio clips are saved and scheduled for transmission. Uses AIR Browser software.

4) Playback: Edited audio signals ready for transmission are played in the

transmission studios before sending it to the control room. AIR Virtual Studio is the software used here.

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CONTROL ROOM

o The control room is the main

technical area of the radio station.

o Switching console does switching

of different sources for transmission,

quality monitoring, level monitoring

and control etc.

o Mixing console is an electronic

device for combining, routing, and

changing the level, timbre and

dynamics of audio signals.

o Studio change-over takes place

here.

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STUDIO TRANSMITTER LINK (STL)

o STL sends a radio station’s audio from the broadcast studio to a radio

transmitter in another location.

o In AIR, the transmission link refers to the communication channel that

connects the studio to the transmitters.

o Links used in AIR:

Microwave links

ISDN ( Integrated Services Digital Network )

Leased line

Captive Earth Station (CES) for satellite uplink.

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EARTH STATION

oAIR requires Captive Earth Stations to uplink its programs for

distribution through satellite.

oMain components:

The BBIF Rack houses the subsystems used in Baseband processing

and Encoding/Modulation of signals.

The HPA Rack houses the subsystems used in upconversion,

amplification of the RF signal.

The Monitoring Rack houses all the receiving equipment for

reception of downlinked signals.

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TRANSMITTERS IN AIR

1. Medium Wave Transmitter Kulathoor

Frequency: 1161 KHz

Power: 20 KW

Band width:9 KHz

Propagation: Ground wave

Antenna: Self Radiating Mast

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TRANSMITTERS IN AIR (Contd…)

2. Short Wave Transmitter Beemapally

Frequencies used : Night-5010

KHz; Day-7290 KHz

Power: 50 KW

Propagation : Sky wave

Antenna: Curtain antenna

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TRANSMITTERS IN AIR (Contd...)

3. FM Transmitter Kudapanakunnu

Frequency: 101.9 MHz

Power: 10KW

Coverage area: 75km

Antenna: Dipole antenna

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CONCLUSION

o We have undergone industrial training at Doordarshan Kendra and All India

Radio, Thiruvananthapuram for a period of 1 month.

o In this training, most of the theoretical knowledge that has been gained

during the course of studies is put to test.

o Both Doordarshan and All India Radio are divisions of Prasar Bharati and is

a mass medium of communication.

o These are Free to Air service providers.

o It was a great experience to learn about the organizations and the

technologies used there.

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QUERIES?

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THANK YOU…