All india radio

all India radio summer training ppt

1. A PRESENTATION OF MAJOR TRAINING AT ALL INDIA RADIO Vocational training period : (11.07.2017-24.07.2017) Presented by :- Sayan Chakraborty Paramita Banik Suman Biswas Md.Ramiz Raza

2. INTRODUCTION For 75 years, AIR has been distinctive part of the Indian way of life . With one of the largest network of SW/MW/FM transmitters, AIR, reaches the remotest corners of the country. All India Radio (abbreviated as AIR), officially known as Akashvani is the radio broadcaster of India and a division of Prasar Bharati .

3. Today AIR has a network of 213 broadcasting centers covering 90% of the area & almost reaching the entire population of one billion. All India Radio is one of the largest radio networks in the world. The headquarters is at the Akashwani Bhavan, New Delhi. The External Services Division of All India Radio broadcasts in 27 languages to countries outside of India.

4. What is Modulation ? Modulation is the addition of information to an electronic or optical carrier signal. A carrier signal is one with a steady waveform -- constant height (amplitude) and frequency. Information can be added to the carrier by varying its  amplitude ,  frequency ,  phase ,  polarizatio n  (for optical signals), and even quantum-level phenomena like  spin .  

5. i ) Amplitude modulation II) Frequency modulation III) Phase modulation. There are 3 basic types of modulation:

6. amplitude modulation  ( am ) is a  modulation  technique used in electronic communication, most commonly for transmitting information via a  radio   carrier wave . in amplitude modulation, the  amplitude  (signal strength) of the carrier wave is varied in proportion to the waveform being transmitted.  What is Amplitude modulation ?

7. i ) Corverage area of AM Reciever is wider than FM because atmospheric propagation ii)AM is long distance propagation iii)AM Circuit is cheapter and non complex than FM. Iv) AM have bandwidth limited and FM unlimited Advantages of amplitude modulation

8. i ) The only one way to withance to noise happen is increasing power transmite ii) Signal of AM is not stronger than FM when it propagate to obstacle. ( Urband ) iii) Only one sideband of AM transmites Information Signal, So it loss power on other sideband and Carrier. Iv) Noise mixes AM Signal in amplitude when it propagates in free space that it make difficulty to recover Original Signal at reciever .  D isadvantages of amplitude modulation

9. in  telecommunications  and  signal processing ,  frequency modulation  ( fm ) is the encoding of  information  in a  carrier wave  by varying the  instantaneous frequency  of the wave. this contrasts with  amplitude modulation , in which the  amplitude  of the carrier wave varies, while the frequency remains constant. What is Frequency modulation?

10. i ) esilient to noise ii) Resilient to signal strength variations Does not require linear amplifiers in the transmitter iii)Enables greater efficiency than many other modes Advantages of frequency modulation

11. i )Requires more complicated demodulator ii) Some other modes have higher data spectral efficiency iii) Sidebands extend to infinity either side Disadvantages of frequency modulation

12. Stages Of a Radio Station Studio Control Room Transmitter

13. RECEIVING CENTRE ANNOUNCER CONSOLE EQUIPMENTS

14. Broadcast Studio A broadcast studio is an acoustically treated room. It is necessary that the place where a programme for broadcast purposes is being produced should be free of extraneous noise. This is possible only if the area of room is insulated from outside sound. The entry to the studios is generally through sound isolating lobby called sound lock. Outside of every studio entrance, there is a warning lamp, which glows Red when the studio is ON-AIR .

15. STUDIO TRANSMITTER LINK

16. PC TURN TABLE MICROPHONE PROGRAM AMPLIFIER TO CONTROL ROOM ANNOUNCER CONSOLE

17. Control Room Mixing Switching Transmitter Amplifiers Modulators Antennas

18. Control Room Broad functions of switching console in control room: Switching of different sources for transmission like News, O.Bs. other satellite based relays, live broadcast from recording studio. Level equalization and level control. Quality monitoring. Signaling to the source location. Communication link between control room and different studios

19. RNT SWITCHING CENTRE STUDIO SWITCHER MIXER PROGRAM AMPLIFIER

20. Mixing Various equipments are available in a studio to generate programme as given below: Microphone, which normally provides a level of 70 dBm. Turntable which provides an output of 0 dBm. Tape decks which may provide a level of 0 dBm. CD and R-DAT will also provide a level of 0 dBm.

21. AMPLIFIER Audio Amplifiers Power Amplifiers Peak Clippers

22. Principle Of Antenna System Antenna is usually a metallic device (a rod or a wire) used for radiating or receiving electromagnetic waves. The radio frequency power developed in the final stage of a transmitter is delivered through cables/feeders, without themselves consuming any power to the transmitting antenna.

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