BIPUL KUMAR GUPTAE.T.&T.

RCET RAIPUR

AT DOORDARSHAN KENDRA (D.D.K.) RAIPUR

VOCATIONAL TRAINING REPORT

OVER VIEW

INTRODUCTION

TV STUDIO EARTH STATION

TRANSMISSION

Doordarshan is an Indian public service broadcaster, a division of prasar bharati. It is one of the largest broadcasting organizations in India in terms of the studio and transmitter infrastructure. Recently, it has also started broadcasting on digital terrestrial transmitters. On 15 September 2009, Doordarshan celebrated its 50th anniversary.

INTRODUCTION OF DOORDARSHAN

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Largest broadcasting organization

1st service started on 15th sep,1959

Doordarshan = distant + show.

Broadcasting started in India in the year 1923.

AIR was formed in the year 1936.

1st T.V Station was established in Delhi in 1959

T.V was separated from AIR in 1976

DD has 1500 Transmitters and 70 Production centers across the Country.

Broadcasting of DD Chhattisgarh started in the year 2002.

T.V was separated from AIR in 1976

A television studio is an installation in which television or video productions take place.

T.V. STUDIO

This is also small studio for special programs

COMPONENTS OF TV STUDIO

Camera Lighting Microphones Vision mixer and Audio consoles MSR VTR Post production and video effects Supporting services like AC, UPS

Camera- camera is an optical instrument that records images that can be stored directly, transmitted to another location, or both. These images may be still photographs or moving images such as videos or movies.

Lighting .

LIGHTING UNIT WITH STAND

LIGHTING WITH UPER SUPPORT

HARD SOURCE(SPOT LIGHT )

COOL

LIGHT

Microphones- Microphones is an acoustic-to-electric transducer or sensor that converts sound in air into an electrical signal. Microphones are used in many applications such as telephones.

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MICROPHON

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Vision mixer and Audio consolesA vision mixer (also called video switcher, video mixer or production switcher) is a device used to select between several different video sources and in some cases mix video sources together and add special effects.

It has many input sources such as cameras, VCR/ server, Graphics/Character Generators ,etc.

Out of these input, any source can be taken as output.

Sources can be changed as cut to cut, dissolve, wipe and other special effects.

AUDIO CONSOLES

THE AUDIO CONSOLES INCLUDES

1.AUDIO MIXING

2.AUDIO PATCH PANEL

3.AUDIO DISTRIBUTION AMP.

4.AUDIO MONITOR

5.OTHER AUDIO SOURCES LIKE CD PLAYER ,USB PLAYER

TYPICAL VIDEO CHAIN

TYPICAL AUDIO CHAIN

DistributorVision Mixer LOGOGenerator

Earth station through

Optical Fiber

Sources

DistributorAudio Console

Analog to AES

Converter

Earth station through

Optical Fiber

Sources

EARTH STATION

MSR (MASTER SWITCHING ROOM) It is the heart of the studio.

Most of the switching electronics is kept e.g. camera base stations, switcher main frame, SPG, Satellite receivers, MW link, DDA & most of the patch panels.

Signal is routed through MSR.

Signal can be Monitored at various stages

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Earth Station is a very important part of satellite communication system for broadcasting of signals.

It is an uplink center from which the signals are fed to Satellite for distribution in a specified area covered by the Satellite.

The signal is up-linked from the Earth Station and received by many down link centers in TV broad casting via PDA.

Two Types: 1) Analog, 2) Digital

Digital Earth Stations are widely used because of various advantages over analog.

EARTH STATION

PDA (Parabolic Dish Antenna)

TRANSMITTER, DIPLEXER AND SET-UP BOX SET IN THE EARTH STATION

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Satellite

Uplink Downlink

EARTH STATION

RECEIVER

STATION PARAMETER OF DDK RAIPUREarth Station site Doordarshan Kendra RAIPUR Shankar nagar

Site longitude 21.25 degree

Site latitude 81.67 degree

Satellite INSAT—4B

Location 93.5 degree east

Transponder C--2

Uplink Frequency 5987 MHz

Downlink Frequency 3762 MHz

Uplink polarization Vertical

Downlink polarization Horizontal

Bandwidth 6 MHz

Uplink Power in Watts 80 --- 100 Watts

Antennas

An antenna (or aerial) is a transducer designed to transmit or receive electromagnetic waves. In other words, antennas convert electromagnetic waves into electrical currents and vice versa.

Electrical signal

Transmitting Antenna

Electromagnetic wave

Receiving Antenna

Yagi Antenna

TRANSMISSION - A television transmitter is a device which broadcasts an electromagnetic signal to the television receivers Television transmitters may be analog or digital.

TRANSMISSION

Types of Transmitters (1)VLPT’s (2)LPT’s (3)HPT’s

A 10 kW HPT of Raipur zone is situated at Shankar nagar Raipur.

A 10 kW HPT is only 10-20% efficient.

It has beam width of 360 degree, hence can cover up to 65 kms of area around it.

It has various other supporting units with it to maintain the quality of s/g to be Txd. Like- Monitoring section, blower section, amplification section

IN DOORDARSHAN SET UP WE HAVE DIFFERENT TRANSMITTER AS PER THEIR RATED POWER AND COVERAGE AREA.

• VERY LOW POWER(VLPT) 5—10 W 5—10 Kms• LOW POWER(LPT) i) 100 W 15—30 Kms ii) 300 W 40 Kms• HIGH POWER(HPT) i) 1KW 60 Kms ii) 10 KW 90—110 Kms

COVERAGE AREA

TRANSMITTER

COVERAGE AREA OF DDK RAIPUR

In Raipur Doordarshan Kendra having 10kw HIGH POWER transmitter (HPT) so its coverage area is approximately 90-110kms.10 KW 90—110 Kms

IN CHHATTISGARH HAVE 16 LPT AND 7 VLPT