02-11-2016, 09:21 AM
Radio is a powerful mass medium used in education for disseminating information, imparting instruction and giving entertainment. It serves with equal ease in both developed and developing countries. It spreads information to a greater group of population thereby saving time, energy, money and man-power in an effective way. Radio is a simple and cheap medium readily available as a small toy. Now small and handy transistors are available with even poorest of people. A small transistor can carry the message to any place on - the earth. It needs very little for maintenance and cheaper production can be taken up with more and more resources. Radio speaks to an individual so also to millions at a time. Hence, any listener can think the broadcast is meant for him whereas when listened in group all think the massage directed towards them. Each student takes the broadcast as very intimate to him. Due to its portability and easy accessibility radio could found its place everywhere whether it was a field, a school, a kitchen or a study room. Radio is a blind man’s medium and is meant for ears only. It plays with sound and silence where the sound can be any thing like voice or word, music and effect. When one hears radio, simultaneously one can imagine happenings in his/her mind. So it is called as theatre of blind or a stage for the mind. Radio can be listened to simultaneously along with another work like reading also.
Radio can be used as an effective and interesting tool in education both for formal and non-formal education. Where conditions have permitted, it has become well established and wide spread; yet, it seems to us that insufficient educational use is made of this virtually universal method of distribution. People often seem to have been deterred by the repeatedly greater efficiency of other media which, however, have the major defect, compared with radio of being unable to cope for such widespread distributions - or anything like it for a long time to come. The very low cost and adequate reliability in all climates of miniature transistor radios mean that radio broadcasting should more and more be recognised as a particularly suitable medium for educational purpose. Radio, in reality, has been used extensively as an educational medium both in developed and developing countries since beginning. Its educational programmes supported in a wide range of subject areas in different countries. Educational radio has also been employed within a wide variety of instructional design contexts. In some cases it is supported by the use of printed material, by local discussion group, and by regional study centres. It is sometimes so designed to permit and encourage listeners’ reaction and comments. Evaluations are also carried out with the feedbacks received.
History of ALL INDIA RADIO In British India broadcasting started in June 1923 with programs by the Radio Club of Bombay. Then, by an agreement of 1926 the private Indian Broadcasting Company (IBC) was granted permission to operate two radio stations; the Bombay station was inaugurated on July 23, 1927, the Calcutta station followed on August 26, 1927. But already on March 1, 1930 the Company went into liquidation. Thus the Government took over the broadcasting facilities, starting the Indian State Broadcasting Service (ISBS) on April 1, 1930 (on experimental basis for two years, but continued in May 1932). On June 8, 1936 the ISBS was renamed All India Radio (AIR; also known as Akashvani since 1956).
3. Principles Of All India Radio transmitting A radio wave carries information signal; Signals are converted into electrical signals. A carrier wave is then produced from the modulation. The wave is then amplified, and sent to the antenna that then converts signal into an E.M. wave. Receiving An antenna on receiving the signal send it to the receiver this then converts the electrical signal sends it to the amplifier either a speaker/headphones jack this is then converted into a sound wave.
4. Methodology of Radio Modulating signal Carrier Wave Modulated Wave Microphon e Broadcast Tower How radio electromagnetic waves are changed to Radio Waves - Radio
5. In Realty it works like this: Phase 1 : Baseband Or the Original signal message signal Phase 2 : After carrier being sent then modulating siganl
6. Studio center Broadcast station Mixing Control room Recording room Dubbing room
7. Microphone Microphone is a device which converts acoustical energy into electrical energy . In the professional broadcasting field microphones have primarily to be capable of giving the highest fidelity of reproduction over audio bandwidth . The first type of studio microphone is the condenser microphone. The second type of studio microphone is dynamic microphone. The third major type of studio microphone is the ribbon microphone .
8. Classification of microphone Pressure Operated Type : In such microphones only one side of the diaphragm is exposed to the sound wave. The output voltage is proportional to the sound pressure on the exposed face of the diaphragm with respect to the constant pressure on the other face. Moving coil, carbon, crystal and condenser microphones are mostly of this type. In their basic forms, the pressure operated microphones are Omni-directional. Velocity or Pressure Gradient Type : In these microphones both sides of the diaphragm are exposed to the sound wave. Thus the output voltage is proportional to the instantaneous difference in pressure on the two sides of the diaphragm.
9. Design of Microphone Microphones can be designed either to respond equally to sounds from an angle or to discriminate those arriving from specific directions. Microphones which respond equally at all angles are called Omni-directional. The microphones which pick up equally from front and rear and have very little pick up equally from sides are called Bi-directional and have a polar diagram as figure of eight. The microphones which pick up maximum from the front with slight reduction in the sides and very less pick up from the rear are called C ardioids (means heart shape).
10. Condenser Microphone This is the simplest type of all studio microphones. They work by converting signals caused by acoustic energy to electrical energy resulting in a stronger signal. Condenser microphones use energy from the studio’s mixing station or from a battery supply to operate.
11. Dynamic Microphone These are the kind of microphones that generate signals by a conductor which is in magnetic field being in motion. The majority of microphones that fall under the dynamic microphone category have a light, very thin diaphragm that gets in motion responding to the pressure of the sound it is exposed to . The motion creates voice coils which are suspended to magnetic fields, making the fields to move which in turn creates electric currents in small quantities. Majority of dynamic studio microphone can operate without external power supply.In many occasions dynamic microphones are used in studios to record drums, electric guitars and the like
Radio can be used as an effective and interesting tool in education both for formal and non-formal education. Where conditions have permitted, it has become well established and wide spread; yet, it seems to us that insufficient educational use is made of this virtually universal method of distribution. People often seem to have been deterred by the repeatedly greater efficiency of other media which, however, have the major defect, compared with radio of being unable to cope for such widespread distributions - or anything like it for a long time to come. The very low cost and adequate reliability in all climates of miniature transistor radios mean that radio broadcasting should more and more be recognised as a particularly suitable medium for educational purpose. Radio, in reality, has been used extensively as an educational medium both in developed and developing countries since beginning. Its educational programmes supported in a wide range of subject areas in different countries. Educational radio has also been employed within a wide variety of instructional design contexts. In some cases it is supported by the use of printed material, by local discussion group, and by regional study centres. It is sometimes so designed to permit and encourage listeners’ reaction and comments. Evaluations are also carried out with the feedbacks received.
History of ALL INDIA RADIO In British India broadcasting started in June 1923 with programs by the Radio Club of Bombay. Then, by an agreement of 1926 the private Indian Broadcasting Company (IBC) was granted permission to operate two radio stations; the Bombay station was inaugurated on July 23, 1927, the Calcutta station followed on August 26, 1927. But already on March 1, 1930 the Company went into liquidation. Thus the Government took over the broadcasting facilities, starting the Indian State Broadcasting Service (ISBS) on April 1, 1930 (on experimental basis for two years, but continued in May 1932). On June 8, 1936 the ISBS was renamed All India Radio (AIR; also known as Akashvani since 1956).
3. Principles Of All India Radio transmitting A radio wave carries information signal; Signals are converted into electrical signals. A carrier wave is then produced from the modulation. The wave is then amplified, and sent to the antenna that then converts signal into an E.M. wave. Receiving An antenna on receiving the signal send it to the receiver this then converts the electrical signal sends it to the amplifier either a speaker/headphones jack this is then converted into a sound wave.
4. Methodology of Radio Modulating signal Carrier Wave Modulated Wave Microphon e Broadcast Tower How radio electromagnetic waves are changed to Radio Waves - Radio
5. In Realty it works like this: Phase 1 : Baseband Or the Original signal message signal Phase 2 : After carrier being sent then modulating siganl
6. Studio center Broadcast station Mixing Control room Recording room Dubbing room
7. Microphone Microphone is a device which converts acoustical energy into electrical energy . In the professional broadcasting field microphones have primarily to be capable of giving the highest fidelity of reproduction over audio bandwidth . The first type of studio microphone is the condenser microphone. The second type of studio microphone is dynamic microphone. The third major type of studio microphone is the ribbon microphone .
8. Classification of microphone Pressure Operated Type : In such microphones only one side of the diaphragm is exposed to the sound wave. The output voltage is proportional to the sound pressure on the exposed face of the diaphragm with respect to the constant pressure on the other face. Moving coil, carbon, crystal and condenser microphones are mostly of this type. In their basic forms, the pressure operated microphones are Omni-directional. Velocity or Pressure Gradient Type : In these microphones both sides of the diaphragm are exposed to the sound wave. Thus the output voltage is proportional to the instantaneous difference in pressure on the two sides of the diaphragm.
9. Design of Microphone Microphones can be designed either to respond equally to sounds from an angle or to discriminate those arriving from specific directions. Microphones which respond equally at all angles are called Omni-directional. The microphones which pick up equally from front and rear and have very little pick up equally from sides are called Bi-directional and have a polar diagram as figure of eight. The microphones which pick up maximum from the front with slight reduction in the sides and very less pick up from the rear are called C ardioids (means heart shape).
10. Condenser Microphone This is the simplest type of all studio microphones. They work by converting signals caused by acoustic energy to electrical energy resulting in a stronger signal. Condenser microphones use energy from the studio’s mixing station or from a battery supply to operate.
11. Dynamic Microphone These are the kind of microphones that generate signals by a conductor which is in magnetic field being in motion. The majority of microphones that fall under the dynamic microphone category have a light, very thin diaphragm that gets in motion responding to the pressure of the sound it is exposed to . The motion creates voice coils which are suspended to magnetic fields, making the fields to move which in turn creates electric currents in small quantities. Majority of dynamic studio microphone can operate without external power supply.In many occasions dynamic microphones are used in studios to record drums, electric guitars and the like