2. HISTORY
1. Doordarshan = Distant + Show
2. One of the largest broadcasting organizations in
India in terms of the infrastructure of studios and
transmitters.
3. Doordarshan is a public broadcast terrestrial
Channel run by Prasarbharati
4. Broadcasting started in India in the year 1923
5. 1st T.V Station was established in Delhi
in 1959
6. T.V was separated from AIR in 1976
7. DD has 1500 Transmitters and 70 Production centers
across the Country.
3. INTRODUCTION
Broadcasting:
Process of sending information to a
distant place is called Broadcasting.
Means of Broadcasting in India:
1.Terrestrial
2.Satellite
3.Internet
Both AIR & DD make use of both Terrestrial & satellite.
5. Some facts about Doordarshan!!!
1.Directly works Under Government Policies .
2. India’s National TV Channel / wireless Broadcasting
Media ( DD National/ DD News / DD sports Etc. )
3. Free To Air Service provider.
4.Not in the race of TRP.
5.Program that comes have information as well as moral
values.
6.Always provide authentic news .
6. CONTENTS
1.Television Standard
2.Studio
3.Camera
4.Television Lighting
5.Acoustic System
6.Vision Mixture
7.MSR
8.Transmitter
9.Earth Station
10.Process of Transmission
1.Television Standard
2.Studio
3.Camera
7. Television Standard
• NTSC-National television standards
committee(US) (525 Horizontal & 60 vertical
lines)
• SECAM-System electronics for colour avec
memory (FRANCE)(625 vertical & 50horizantal
lines)
• PAL- Phase Alternating lines(GERMANY)(625
horizontal & 50 vertical line)
Television standards used in India is PAL
8. PAL ENCODER & DECODER
•Input is the primary colour (i.e.
red, green, blue) into matrix circuit
as Y, R-Y, B-Y.
•Y=0.30R+0.59G+0.11B
•U=0.477(R-Y)
•V=0.895(B-Y)
•Out of 625 horizontal line only 575
are active
•50 vertical lines
9. Studio
A television studio is an installation in which
television or video productions take place by using several
supporting equipments
10. Type Of Studio
Studio A (Main)
Studio A requires four cameras.
Studio A is used for recording of programmes and other
activities.
11. Studio B (News)
Studio B requires two cameras.
Studio B is used for News recording & regional
transmission.
12. COMPONENTS OF TV STUDIO
•Camera
•Lighting
•Microphones
•Vision mixer and Audio consoles
•MSR
•VTR
•Acoustics
•Post production and video effects
•Supporting services like AC, UPS
13. Camera
A TV camera consist of three section.
Optical part - To form optical image.
Transducer - To convert optical image in to electrical
signal.
Electronic part - To process output of a transducer to
get a CCVS (colour composit video signal).
CCD Camera are used for recording
14. TELEVISION LIGHTING
Doordarshan studio has three basic
lights :-
Key light – This is the principal light
source of illumination. It is hard light which
provides shining on the front part of
objects.
Fill light – It controls the lighting
contrast by filling in shadows.
Back light – It separate the objects from
the background .
15.
16. Acoustic System
It is derived from a Greek word “akoustos” which
means “hearing”.
It is use to prevent sounds from it’s echo.
In Doordarshan studio , all the sound must have
to be done Acoustic treatment to preserve the
originality of the sound along with extending
maximum pleasure to the listener.
17. Vision Mixer
A vision mixer 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 i/p, any source can
be taken as o/p.
Sources can be changed as cut to
cut, dissolve, wipe and other special
effects.
18. Typical video chain
1-Use PAL system (720*576) in 4:3 aspect ratio.
2-For TV Transmission It uses VSM .
3-It Uses C Band( DTH uses Ku band) and in the transmitter
room it has two 10 KW Transmitters for Broadcasting.
19. 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
20. Camera control unit
CHARCTER
GENERATORS
CONTROL APPARATUS
ROOM
Includes the power
supply unit UPS room.
VIDEO TAPE RECORDER
Consists of recorded
materials i.e. v.c.R
21. TRANSMITTER
A television transmitter is a
device which broadcasts
an electromagnetic signal to
the television receivers.
AlsoConnect earth station to
satellites
22. Earth station
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.
23. THE PROCESS OF TRANSMISSION
EARTH
STATION TANSMITTER/RECEIVER
SATELLITE
DTH
RECEIVER
TV
UPLINKING
DOWNLINKING
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