VOCATIONAL TRAINING ON A.I.R

PRESENTED BY :RAJEEB AUDDYAVISHEK DAS

SUDIPTA RANJAN PALIT

Basic Programme Chain at ALL INDIA RADIO

STUDIO

OUTSIDE

C-BandUPLINK

S-BandUPLINK

S-BandDownlink

EQA

CONTROLROOM

DTH Downlink

AUDIO SELECTOR SWITCHPROG INPUT RACK(TR HALL)

EARTHSTATION

P&T Line

DTH

C-B

and D’LIN

K

S-Band D

’LINK

DIG

TAL LIN

K

MW

LINK

FM LIN

K

DTHUplink

C-BandDownlink

LIMITER TRANSMITTER

Source of Programmes

Internal: Studio BroadcastingExternal : Outside Broadcasting

AUDIOSOURCE

(CONTROL ROOM)

Internal:a) Studiosb) Linkedc) NEWS

External:a) Live eventb) Sports event

Categories of station• Transmitter + Studio ( Co-sited)

( FM Station)• Transmitter + Studio ( Non Co-sited)

( FM & AM Station)• Transmitter

( Relay Centre , HPT , SPT)

CONTROL

ROOM

Satellite Uplink EARTH STATION

SB

andC

B

and

C BandUplink Terminal

S BandUplink Terminal

Downlink Frequency

Frequency range (Down link)

• (i) S-Band = 2.5 to 2.7 GHz

• (ii) C-Band = 3.7 to 4.2 GHz

• (iii) Ex-C Band= 4.5 to 4.8 GHz

Uplink Frequency

(i) Uplink freq. for S-Band

=Down link freq. + 3300 MHz (ii) Uplink freq. for C-Band/

=Down link freq. + 2225 MHz

(iii) Ex. C Band

C - BandUplink Terminal

C - BandDownlink Terminal

(DTH Uplink Station)

DTH Uplink Terminal(Ku-Band)

Important Audio Parameter

Frequency ResponseSignal to Noise Ratio (SNR)

S – BandUplink

C – BandUplink

Ku – BandUplink(DTH)

S – BandDownlink

C – BandDownlink

Ku – BandDownlink(DTH STB)

AUDIO SELECTOR SWITCH(PROG INPUT RACK AT TR HALL)

AUDIOINPUT

SELECTOR SWITCH

PROGINPUT RACK

(at TR HALL)P & T Line

FM Link

Satellite Downlinks

E1 Connectivity ( Limited )

Digital Link

STL Link (Microwave)

DTH Downlinks

AUDIO SELECTOR SWITCH(PROG INPUT RACK AT TR HALL)

EQUALISED LINE AMPLIFIER

LIMTING AMPLIFIER

EQAAUDIO SELECTOR SWITCHPROG INPUT RACK(TR HALL) LIMITER

TRANSMITTER

TRANSMITTER RECEIVER

What is the basic recognition of a Radio Transmitter?

It’s

Carrier Frequency

What is the power of a Radio Transmitter?

It’s

Rated Carrier Power

What are the basic types of Modulation?

• Amplitude Modulation

• Frequency Modulation

• Digital Modulation

An audio signal (top) may be carried by an AM or FM radio wave.

What are the basic type of Radio Transmitter?• AM Transmitter

• FM Transmitter

• Digital Transmitter

What are the basic type of AM Transmitter?

• 10 kW• 2 X 10 kW• 100 kW• 2 X 100 kW • 300 kW • 2 X 500 kW

What are the basic types of FM Transmitter?

• 3 kW• 2 X 3 kW• 5 kW• 2 X 5 kW• 2 X 10 kW

Generation ofRF Signal

Modulator

Processing of AF Signal

HarmonicFiltration

Basic Chain of Radio Transmitter

Exciter10 W

PowerDivider

PowerDivider

POWERAMP

POWERAMP

POWERCombiner

POWERAMP

POWERAMP POWER

Combiner

POWERCombiner

PowerDivider

HF

HF

HF

HF

Basic Block Diagram of FM Transmitter

Thank you!