A Presentation

ON

“SUMMER TRAINING”

TAKEN AT

DOORDARSHAN KENDRA, JAIPUR SESSION: - 2010-2011

DURATION: - 10-05-2010 TO 15-06-2010

. .

INDEX

1.Microphones2.Satellite Communication & Earth Station3.T.V. Studio4.VTR, LE & NLE5.Audio & Video Chain6.Vision Mixer7.DSNG, Outdoor Broadcasting8.Transmitter

1. Microphone1. Microphone

In all microphones, sound waves (In all microphones, sound waves (sound pressure) are translated into ) are translated into

mechanical vibrations in a thin, flexible mechanical vibrations in a thin, flexible diaphragm. These sound vibrations are . These sound vibrations are then converted by various methods into then converted by various methods into

an electrical signal which varies in voltage an electrical signal which varies in voltage amplitude and frequency in an amplitude and frequency in an analog of of

the original sound. For this reason, a the original sound. For this reason, a microphone is an acoustic wave to microphone is an acoustic wave to

voltage modulation voltage modulation transducer..

Placement of MicrophonesPlacement of MicrophonesMicrophone should be placed with its 0 axis Microphone should be placed with its 0 axis facing the source of sound to avoid off axis facing the source of sound to avoid off axis

colouration.colouration.

When two or more Microphones are used, it When two or more Microphones are used, it should be ensured that their outputs are in should be ensured that their outputs are in

phase.phase.

The Microphone should not be too close or too The Microphone should not be too close or too far to the sound source. far to the sound source.

When the Microphone is close to the sound When the Microphone is close to the sound source, direct sound is predominant and source, direct sound is predominant and

hence the outputhence the output

Lip MicrophoneLip Microphone Lapel MicrophonesLapel Microphones

Sphere MicrophoneSphere Microphone Boundary MicrophoneBoundary Microphone

OmnidirectionOmnidirectionalal

CardioiCardioidd

HypercardioiHypercardioi

dd

Bi-directionalBi-directional

ShotgunShotgun

PATTERNS OF DIFFERENT TYPE OF ANTENNAS

2. Satellite Communication 2. Satellite Communication

• Started in 1960.Started in 1960.

• Uses Geo Stationary Satellite.Uses Geo Stationary Satellite.

• Operates in C-Band & Ku-Band .Operates in C-Band & Ku-Band .

• Started in India in 1975 .Started in India in 1975 .

• First Indian Satellite INSAT launched in 1982 .First Indian Satellite INSAT launched in 1982 .

• Gulf War brought satellite television to prominence.Gulf War brought satellite television to prominence.

Uplink Station

DownlinkUplink

Satellite CommunicationSatellite Communication

Receive CentreApril 11, 2023

Purpose of Satellite Purpose of Satellite CommunicationCommunication• A single satellite can provide coverage to over A single satellite can provide coverage to over

30% of Earth’s surface.30% of Earth’s surface.

• It is often the only solution for developing It is often the only solution for developing areas.areas.

• It is ideal for broadcast applications.It is ideal for broadcast applications.

• It can be rapidly deployed.It can be rapidly deployed.

• It is scalable.It is scalable.

• Depending on application, there is no need for Depending on application, there is no need for the local loop.the local loop.

• Transmission cost is independent on distance.Transmission cost is independent on distance.

• One hop from the backbone, wherever you are.One hop from the backbone, wherever you are.

• Wide bandwidths (155 Mbps) are available now.Wide bandwidths (155 Mbps) are available now.

Satellite Transmission Satellite Transmission Frequency bandsFrequency bands

Frequency bandFrequency band Up Link Up Link Down Down LinkLinkC-band 6 GHz 4 GHzC-band 6 GHz 4 GHzX-band 8 GHz 7GHzX-band 8 GHz 7GHzKu-band 14 GHz 11 GHzKu-band 14 GHz 11 GHzKa-band 30 GHz 20 GHzKa-band 30 GHz 20 GHz

• Why uplink frequency is always higher than Why uplink frequency is always higher than downlink frequency ?downlink frequency ?

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

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

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

Digital Communication SetupDigital Communication Setup

Channel encoding: Channel encoding: Introduce controlledIntroduce controlledredundancy redundancy ARQ, FECARQ, FEC

Source encoding Channel encoding

User Source decoding Channel decoding

Transmission channel RF Stage

Digital source Mod..

Detector

Source encoding:Source encoding:Remove redundancyRemove redundancy

Base Band Signal

Compression & IF stage

3. TV STUDIO3. TV STUDIO

• CameraCamera

• LightingLighting

• MicrophonesMicrophones

• Vision mixer and Audio consolesVision mixer and Audio consoles

• MSRMSR

• VCR/ ServersVCR/ Servers

• AcousticsAcoustics

• Post production and video effectsPost production and video effects

• Supporting services like AC, UPS Supporting services like AC, UPS

STUDIO SET UP AT DDK JAIPURSTUDIO SET UP AT DDK JAIPUR

2 Studio; one for major recordings & 2 Studio; one for major recordings & other for News and small recordings.other for News and small recordings.

Main studio has 4 camera set up, size Main studio has 4 camera set up, size is 400 sq mtr while small one has 3 is 400 sq mtr while small one has 3 camera set up. Camera are 3 CCD camera set up. Camera are 3 CCD

types.types.

MSRMSR

It is the heart of the studio.It is the heart of the studio.

Most of the switching electronics is Most of the switching electronics is kept e.g. camera base stations, kept e.g. camera base stations,

switcher main frame, SPG, Satellite switcher main frame, SPG, Satellite receivers, MW link, DDA & most of the receivers, MW link, DDA & most of the

patch panels.patch panels.

Signal is routed through MSR.Signal is routed through MSR.

Signal can be Monitored at various Signal can be Monitored at various stages.stages.

Linear Editing Systems?Linear Editing Systems?

Linear Editing systems require edits to be Linear Editing systems require edits to be

made in linear fashion i.e. 1-2-3 sequence.made in linear fashion i.e. 1-2-3 sequence.

One or more tapes containing original One or more tapes containing original

footages are transferred segment by segment.footages are transferred segment by segment.

Source Machines contain the original footage Source Machines contain the original footage

and the desired segments are transferred to and the desired segments are transferred to

edit recorder under the control of an edit edit recorder under the control of an edit

controller.controller.

4. VTR

What is Non-linear What is Non-linear Editing?Editing?

Non Linear Editing is a computer based editing

process.

It is also called random access editing, which allows

you to manipulate video, audio and graphics like text

in a word processor

It allows segments to be inserted, deleted and moved

around at any point in the editing process

It allows to make any changes last moment and

distribute in any format

5. TYPICAL AUDIO CHAIN5. TYPICAL AUDIO CHAIN

Audio ConsoleSources Distributor

Earth station through

Optical Fiber

STLLink

Analog to AES Converter

Components of Audio Chain

1. Microphones

2. VCD / DVD Audio

3. Live Feeds

4. Satellite Feeds

5. Studio Console

6. Switching Console / Master Switching Console

7. Microwave Link Etc.

STUDIO CHAIN (Audio)STUDIO CHAIN (Audio)(Block Diagram)(Block Diagram)

Pre-Amp.

Pre-Amp.

Pre Amp.

VTRRoom

CD/VCD/DVD

Out SideFeeds

Satellite Feeds

MW link

PROGRAMPROGRAMAMPLIFIERAMPLIFIER

PROGRAMPROGRAMAMPLIFIERAMPLIFIER

Stand By

AUDIO

SW

CONSOLE

MSR

Feed Room

For Monitoring

MSR VTR

Audio Distribution

Amplifier(ADA)

VTRRoom

Audio Distribution

Amplifier(ADA)

Stand by

Micro Wave Link

Pre-Amp.

5.TYPICAL VIDEO CHAIN5.TYPICAL VIDEO CHAIN

DistributorVision MixerLOGO

Generator

Earth station throug

Optical Fibre

STLLink

Sources

6. VISION MIXER6. VISION MIXER A vision mixer or production switcher is one of A vision mixer or production switcher is one of the primary device used to produce a television the primary device used to produce a television program. Production switchers are essential to program. Production switchers are essential to

all live operations.all live operations.

Production switcher is used to either switch or Production switcher is used to either switch or cut between two video sources, or to combine cut between two video sources, or to combine

them in a variety of ways.them in a variety of ways.

The principal methods used to combine video The principal methods used to combine video are- Mixing, Wiping,& Keying.are- Mixing, Wiping,& Keying.

7. DSNG7. DSNG• The word DSNG means DIGITAL SATELLITE NEWS The word DSNG means DIGITAL SATELLITE NEWS

GATHERING. it is just like a Digital Earth Station. GATHERING. it is just like a Digital Earth Station. Programme may be up-linked through DSNG from Programme may be up-linked through DSNG from any place. Its up-linking chain have a MPEG-2 any place. Its up-linking chain have a MPEG-2 Encoder, Modulator, Up-converter, HPA, wave Encoder, Modulator, Up-converter, HPA, wave guide mechanism and PDA. HPA consists of guide mechanism and PDA. HPA consists of traveling wave tube Amplifier. traveling wave tube Amplifier.

• SatelliteSatellite offers the unique possibility to offers the unique possibility to transmit images and sound from almost anywhere transmit images and sound from almost anywhere on the planet. From a fully equipped uplink truck or on the planet. From a fully equipped uplink truck or from a light flyaway travel case, from a light flyaway travel case, DSNG makes it DSNG makes it possible to bring live news and sport to possible to bring live news and sport to millions of viewersmillions of viewers. .

Early DSNGEarly DSNG

Digital Satellite News Gathering (DSNG)

Present DSNG Present DSNG PDA SystemPDA System

Based on POWER:-Based on POWER:-VLPT / Transposer (10W)VLPT / Transposer (10W)

LPT (100W, 300W, 500W)LPT (100W, 300W, 500W)

HPT (1kW, 10kW, 20kW)HPT (1kW, 10kW, 20kW)

Based on FREQUENCY:-Based on FREQUENCY:-VHFVHF

UHFUHF

8. TRANSMITTERS

EXCITERTRANSISTOR POWER AMPLIFIER (TR PA)OUTPUT SECTIONCOOLING SECTIONCONTROL SYSTEM

HPT FUNCTIONNING