Vocational Training

Report

HELD AT

DOORDARSHAN

KENDRA

MANDI HOUSE, COPERNICUS MARG

NEW DELHI, 110001

SUBMITTED BY

S A K E T R A I

ECE 4th Year, Roll No. 1003031097

INDERPRASTHA ENGINEERING COLLEGE, GZB,

U.P.

ACKNOWLEDGEMENT

This report is an outcome of industrial training, which I

have gone through at Doordarshan Kendra, Mandi

House, Copernicus Marg, New Delhi, 110001; during the

period 10th Jun to 9th Jul 2013.

On the very outset of this report I would like to express

my sincere & heartfelt obligations to:

DDG (E): Shri Shyam Narain Singh,

DD (E): Shri Rakesh Kumar Chauhan,

Assistant Er. : Shri R. N. Rai (Mentor),&

All engg. Supporting staff: Sh. Vinod Gupta, Sh. S. K. Dixit, Sh.

S. P. S. Gulati, Sh. P. K. Mehrotra, Sh. P. Arun, Sh. Prashant

Shingle, Sh. Govind Ballabh, & Sh. T. C. Bagauli for creating

tremendous atmosphere of excitng training programme

at DDK.

It was really a great experience working at DDK and

learning from such experienced engineers with hands on

the experience on the subject.

I also would like to appreciate my colleagues Mr.

Prashant Kr. Shukla, Mr. Pulkit Jain & Mr. Rahul Aurora,

who attended the entire training with me as per the

scheduled by DDK.

Saket Rai

ECE 4th Year, 1003031097

INDERPRASTHA ENGG. COLLEGE, GZB, U.P.

INDEX

Sr. No. Topic Page No.

1. About Doordarshan 01- 02

2. TV Studio 03-06

3. Production Control Room 07-09

4. Transmission Control Room 10-12

5. Master Switching Room 13-14

6. Earth Station 15-19

7. Satellite Communication 20-24

8. HPT Pitampura 25-28

9. OB Van 29-32

10. DSNG 33-35

11. DD Archives 36-38

12. Essence 39-40

ABOUT ……..

DOORDARSHAN KENDRA DELHI is one of the oldest

Kendra started on experimental basis on 5th September

1959 from a makeshift studio at Akashvani Bhawan,New

Delhi as a part of All India Radio.

Regular transmission was started from 1965.

Govt. of India constituted Doordarshan in 1976, as a

public TV broadcaster, as a separate department in

broadcasting.

Actually, Doordarshan developed itself during Asian

Games 1982, held in Delhi.

Continuous development in each & every sections of

Doordarshan has made it one of the largest broadcasting

organization in the world in terms of infrastructure of

studios & transmitters.

Presently Doordarshan operates with 35 channel

classified as:

Seven All India Channels-

1. DD National,

2. DD News,

3. DD Sports,

4. DD Bharati,

5. DD Rajya Sabha,

6. DD Gyandarshan,

7. DD Urdu;

Eleven Regional Language Satellite Channels(RLSC),

Fifteen State Network (SN) & International Channels,

One DD India Channel,

One HDTV Channel;

Doordarshan is also providing multi channel TV coverage

in country through it’s free to air service; DD Direct Plus.

DD is also running a mobile television service in Delhi.

T V Studio

Doordarshan shooting arena is termed as TV Studio.

Basically, it is a production hall to shoot out various

programs by just creating artificial sets as per

requirements.

Followings are the pre- requisites for a TV Studio:

1. Lighting systems, winches & control boards

2. Cameras (3/4) with teleprompter

3. Video & Audio Monitors

4. Make room with entire facilities

5. Furnitures & decoration items

6. Cyclorama &curtains

7. Proper air conditioning systems

8. Efficient sound absorbers

9. Smooth & plain surface to move cameras

10. Effective communication with other sections

11. Digital clock display system

12. Warning light, alarm systems & fire fighting equipments.

Doordarshan’s main Recording TV Studio comprises 192

direct lights, 48 dimmers, 3 /4 digital cameras & 3 /4

artificial shooting sets etc.

T V Studio lighting technique:

T V Studio lighting technique depends upon following

four parameters -

1. Quantity of Iight:

Means amount of radiated energy by the source of

light. 2. Quality of light:

Means the type of light source is used.

3. Contrast ratio:

Difference between highly lighted & darkest part of

the scene.

4. Color temperature:

Different light colors have their own temperatures

e.g.-

Fire- 1930K,

Domestic lamp- 2780K,

Studio lamp- 3200K,

HMI-5600K,

Sun light- 5600K,

Fluorescent- 6500K,

Cloudy day- 6500K,

Clear blue sky-12000K.

In T V Studio standard three point lighting technique is

used, as shown below:

1. Key light: used to highlight an object from the front.

(Hard light cum 100% balance of light)

2. Fill light: used to suppress the shadow created by key

light. (Soft light cum 85% balance of light)

3. Back light: used to separate the object from back

ground, so to produce 3-D visualization.

(Hard light cum 110% balance of light)

Production Control

Room

Production Control Room (PCR) is also known as Studio

Control Room (SCR) or Gallery. Signals generated in TV

Studio are controlled using certain effects & characters

are generated here.

Facilities in a PCR include:

A video monitor wall, with monitors for program, preview, VTRs, cameras, graphics and other video sources. In some facilities, the monitor wall is a series of racks containing physical television and computer monitors; in others, the monitor wall has been replaced with a virtual monitor wall (sometimes called a "glass cockpit"), one or more large video screens, each capable of displaying multiple sources in a simulation of a monitor wall.

A vision mixer, a large control panel used to select the multiple-camera setup and other various sources to be recorded or seen on air and, in many cases, in any video monitors on the set. The term "vision mixer" is primarily used in Europe, while the term "video switcher" is usually used in North America.

A professional audio mixing console and other audio equipment such as effects devices.

A character generator (CG), which creates the majority of the names and full digital on-screen graphics that are inserted into the program lower third portion of the television screen

Digital video effects, or DVE, for manipulation of video sources. In newer vision mixers, the DVE is integrated into the vision mixer; older models without built-in DVE's can often control external DVE devices, or an external DVE can be manually run by an operator.

A still store, or still frame, device for storage of graphics or other images. While the name suggests that the device is only capable of storing still images, newer still stores can store moving video and motion graphics.

The technical director's station, with waveform monitors, vector scopes and the camera control units (CCU) or remote control panels for the CCUs.

In some facilities, VTRs may also be located in the PCR, but are also often found in the central apparatus room

Intercom and IFB equipment for communication with talent and television crew

A signal generator to genlock all of the video equipment to a common reference that requires color burst

TRANSMISSION

CONTROL ROOM

Transmission Control Room (TCR), also termed as Tx Room or Presentation Suites is a room at broadcast facilities & TV Stations around the world.

TCR is staffed 24x7 by on-air presentation coordinators who are responsible for the continuity and punctual play out of scheduled broadcast programming.

Programming may be live from the TV Studio or played from video tapes or from video server play out.

When broadcast programming is live the presentation coordinator will override the broadcast automation system & manually switch the TV Programming.

Live Programming is unpredictable and will affect the scheduled timing of scheduled programming events; the presentation coordinator adjusts programming to bring the schedule back on time by adding or removing fill content from the play out schedule.

Common TCR equipments

Broadcast Automation Server (for large playlist items

almost up to 500 items),

Video Tape Recorder (VTR),

Computer Graphics (CG),

Non-linear Editing device,

Production Switcher,

Broadcast quality Video Monitor,

Waveform Monitor,

SDI Audio de-embedder.

There are total 72 electronic equipments of

aforementioned type in the Transmission Control Room

of DD National.

Basically, the automation of various PCR equipments is

done in order to achieve seamless transmission. It is also

required to minimize the time elapse as well as manual

errors occurred during transmission.

Each & every equipment has its own defined port on

Production Switcher. Applying automation one can

switch the particular device at particular time.

Finally, these equipments are connected to a Navigation

PC through a Hub Switch for error diagnosis purpose.

TCR is smaller in size as compare to the Master Switching

Room. This is a scaled down version of centralcasting.

MASTER SWITHING

ROOM

Master switching room (MSR) is also known as “Heart of the Studio” and used for transmission media. It is the engineering co-ordination center of activity for selecting & routing the signal from various sources to transmitter and earth station. It is a room where all different sources from the outside studio comes first here and enroots transmission to different destination like transmitter & earth station. This room comprises of: Routine Switcher, Stab amplifier, Video / Audio distribution amplifier, Color Stabilization amplifier, Sync generator, Frame synchronizer, Digital clock monitoring system, Logo generator, Vectro- scope, Waveform monitor, Video monitor, Hum Suppressor,

Video Equalizer, Change over unit. The CONTROL CONSOL PANEL consisting the control of Routine Switcher, Stab amplifier, Frame synchronizer & other MSR Equipments are stored here.

EARTH STATION

EARTH STATION is most significant part of Doordarshan

from communication point of view, as shown in figure:

Transmitting E/S Receiving

E/S

UPLINK

DOWNLINK

Digital Earth Station operates in frequency range 5.85

GHz to 6.425 GHz for transmission and 3.625 GHz to 4.24

GHz for reception of the signal.

Description of General Configuration of an Earth Station:

• Digital information in the form of binary digits when

enters earth station and is then processed (filtered,

multiplexed, formatted etc.) by the base band

equipment.

• The encoder performs error correction coding to

reduce the error rate, by introducing extra digits into

digital stream generated by the base band equipment.

• The function of the modulator is to accept the symbol

stream from the encoder and use it to modulate an

intermediate frequency (I.F) carrier.

In satellite communication, I.F carrier frequency is

chosen at 70 MHz for communication using a 36 MHz

transponder bandwidth.

• The modulated I.F carrier is fed to the up-converter

and frequency-translated to the uplink R.F frequency of

C-Band or Ku-Band as per desire.

• This modulated R.F carrier is then amplified by the

high power amplifier (HPA) to a suitable level for

transmission and radiation by the parabolic dish antenna

to the satellite. e.g.: Klystron amplifier, TWTA & SSPA.

• On the receive side, the earth station antenna

receives the low-level modulated R.F carrier in the

downlink frequency spectrum.

• The low noise amplifier (LNA)/ low noise block

convertor (LNBC) is used to amplify the weak received

signals and improve the signal to Noise ratio (SNR). The

error rate requirements can be met more easily.

• R.F is to be reconverted to I.F at 70 MHz because it is

easier design a demodulation to work at such

frequencies than in any of the GHz range.

• The demodulator estimate which of the possible

symbols was transmitted based on observation of the

received I.F carrier.

• The decoder performs a function opposite that of the

encoder. Because the sequence of symbols recovered by

the demodulator may contain errors, the decoder must

use the uniqueness of the redundant digits introduced by

the encoder to correct the errors and recover

information-bearing digits.

• The information stream is fed to the base-band

equipment for processing for delivery to the terrestrial

network.

• The downlink Beacon frequency is the concept, so

that tracking equipments track the satellite and align the

beam towards it to facilitate communication.

Fig. General configuration of an Earth Station

SATELLITE

COMMUNICATION

Satellite Communication plays a vital role in the global

telecommunication systems.

This technology was started in abroad in 1960, and in

India this was adopted in 1975.

Near about 2000 artificial satellites are orbiting Earth

relay analog & digital signals carrying voice, video and

data to & from one or many locations worldwide.

Satellite communication uses geostationary satellite and

operates in C & Ku band mostly.

First Indian National Satellite (INSAT) was launched in

1982.

Satellite Orbits: Types

Geostationary satellite:

A circular orbit 35,785 km (22,236 miles) above Earth’s Equator in which a satellite orbital period is equal to Earth’s rotation period of 23 hours and 56 minutes. A space craft in this orbit appears to an observer on Earth to be stationary in the sky. This particular orbit is used for meteorological and communications satellites. The geostationary orbit is a special case of geosynchro- nous orbit, which is any orbit with a period equal to Earth’s rotation.

Satellite Transmission Frequency Bands:

Frequency Band

• C-Band

• X-Band• Ku-Band

• Ka-Band

Uplink Frequency

• 6 GHz

• 8 GHz• 14 GHz

• 30 GHz

Downlink Frequency

• 4 GHz

• 7 GHz• 11 GHz

• 20 GHz

Satellite in Use:

Orbit type: Geo-synchronous

Orbital location: 93.5° E

Presently Doordarshan is using a latest, powerful &

largest geosynchronous satellite of INSAT series with high

power Ku- Band transponders to uplink the DD direct +

signals launched by ISRO in the beginning of the year

2007.

Figure: Footprints of INSAT 4B

Communication Satellite Transponders:

A communication satellite transponder is the series of

interconnected units, which forms a channel between

transmitting and receiving antennas. It is mainly used to

transfer the received signal, after deriving the transmit

carrier frequency from received signal.

It’s block diagram presentation is as follows:

HPT PITAMPURA

Dr. B. R. Ambedkar T V Tower (20kw power)

Total height: 235mtrs=RCC: 165mtrs+Steel: 70mtrs.

H P T stands for High Power Transmitters, which is

basically used for terrestrial transmission.

It is noticeable that about 92% population in India can

receive Doordarshan programs through the networks of

1415 terrestrial transmitters.

H P T Pitampura is started in Delhi on 7th Nov. 1988 by

Hon’ble Sh. Rajiv Gandhi the Prime Minister of India.

Total Area: = Covered Area: + Open Area:

16.155sqmtrs. = 2.105sqmtrs. + 14.050sqmtrs.

Coverage Area is about 85km radius in NCR as shown:

There is certain excellent information regarding:

TRANSMITTERS

DD NATIONAL DD NEWS

Channel no CH#5 CH#7

Power of Transmitter

20 KW 20 KW

Frequency of Vision Carrier

175.25 MHZ 189.25 MHZ

Frequency of Aural Carrier

180.75 MHZ 194.75 MHZ

EARTH STATION

DOWNLINK PARAMETERS

FREQUENCY : 3925 MHz

POLARISATION : HORIZONTAL FEC : 3/4

SYMBOL RATE : 27.5MSPS

BAND WIDTH : 36 MHz

O B VAN

Outside Broadcasting (OB) VAN is the electronic

field production i.e. EFP of television or radio

programs (typically to cover television news and

sports television events) from a mobile remote

broadcast television studio.

OB VAN is nothing but a mobile Production Control

Room (PCR) which is also known as production

truck/scanner/mobile unit/remote truck /live truck.

Interior

A typical OB VAN is usually divided into 5 parts:

1. Video Production Area:

This is the first & largest part of OB VAN, where video

production takes place. Video Switcher operated by

Technical Director and Video Monitors (showing various

video feeds) operated by TV Directors & TV Producers

are the main parts of this area. Figure:

2. Audio Production Area:

This is the second part of OB VAN, where audio

production takes place. Here Audio Mixers (being fed

with various audio feeds: reporters, commentary, on-

field microphones) are operated by Audio Engineers.

3. Video Tape Recording Area:

The third part of OB VAN is VTR area, which is nothing

but the collection of video server, house addition power

supplies or computers equipments. Here the EVS (LSM)

operators having one or more cameras that go into their

machines & can be played back in slow motion/pause

to show a key part of action during the game , and can

also play the replay rollouts that lead into commercial

breaks or show the highlights at the end of play.

4. Video Control Area:

The fourth part of OB VAN is Video Control Area

,where the professional video cameras are controlled

using “ Camera Control Unit” i.e. CCU by one or two

operators, to make sure that the iris is at the correct

exposure and that all the camera look at the same.

They can shade, balance, and focus the cameras from

this position inside the truck.

5. Transmission Area:

The fifth part of OB VAN is Transmission Area, where

the signal is monitored by engineers( to ensure the

people at the home have a good picture and a good

quality signal). Further this signal is transmitted or sent

to other trucks.

LAYOUT OF OB VAN:

DSNG

D S N G ie Digital Signal News Gathering is a system that

combines two technologies namely E N G ie Electronic

News Gathering with S N G ie Satellite News Gathering.

E N G is a broadcast news industry description of T V

producers,reporters & editors; making use of electronic

video & audio technologies for gathering & presenting

the news. It is less frequently used now because this

technology has become less ubiquitous.

S N G is the use of mobile communications equipment

for the purpose of worldwide news casting. Mobile units

are usually vans equipped with advanced, two way video

& audio transmitters & receivers, using dish antennas

that can be aimed at geostationary satellites. The earliest

SNG equipment used analog modulations eg: extensively

used in desert shield & desert storm operation in Persian

Gulf. But durring 1980, digital modulation supplanted the

analog modulation; giving rise to the newer technology

called D S N G.

The modern D S N G is a sophesticated affair , capable of

deployment practically anywhere in the civilized world.

The signals are beamed between a geostationary satellite

& van, and between satellite & control room bybroadcast

station or network. In most advanced systems Inter -

national Protocol(IP) is used.

Basically ,it is used for uplink of the gathered news

signals.Digital modulation tecnique applied here saves

the bandwidth.

Let us see the curbside view of D S N G van:

DD ARCHIVES

DD ARCHIVES is located at AKASHVANI BHAVAN,

Parliament Street, New Delhi.

This place is the treasure house of many memorable

performances of the great artists, who have contributed

to India’s rich music and dance heritage. This is amazing

endeavor done to bring some of exquisite performances

of enduring beauty to reach out the larger audience

celebrating the spirit of singing and dancing nation.

This section is equipped with following features:

1. Tape cleaning equipments for different formats.

2. Multi format preview suits.

3. Multi format debugging suits (with facility of Grass

Valley High Quality Noise Reduction System.)

4. Snell Wilcox High Quality Digital Restoration

Archangel Ph-C System.

5. DPS Velocity & Adobe Premier Pro Non Linear

Editing System (with facility of Diamond for video

restoration & Audition for audio restoration.)

6. Different Graphics Systems.

7. DVD burning equipments.

8. Tape Library Metadata System.

9. Different format tape libraries with compactors.

10. Media Asset Management System.

WHAT ACTUALLY DD ARCHIVES DOES???

1. To take the Old tapes from library

2. Cleaning of tapes as per their legacy formats

AMPEX (1972): manual cleaning

Umatic (1982): cleaned by RTI cleaner

BCN (1982): cleaned by RTI cleaner

Beta (1985): cleaned by RTI cleaner

DVC (modern): cleaned by RTI cleaner

3. Preview operation

4. Debugging operation

5. Restoration through DVC Pro 50:

Either in Archangel Ph-C System

Or in Puritan System

6. Restored output is fed to:

Server purpose

Commercial purpose

To keep in library

ESSENCE Different Possible Pathway for the :

TRANSMISSION Upto SATELLITE

1. TV Studio + PCR + TCR + MSR >> Transmitting E/S

>> Satellite:

2. OB Van + DSNG Van >> Satellite:

RECEPTION Upto HOME

1. : Receiving E/S + Terestrial Transmitters >> Yagi-

Uda Antenna + TV Screen.

2. : Reception by private dish + TV Scree.

3. : Reception by cable operator Receiver >> Cable

TV Network >> TV Screen.

SATYAM SHIVAM SUNDARAM

DOORDARSHAN KENDRA DELHI

THE END