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AIR (ALL INDIA RADIO)

Prasar Bharati (Broadcasting Corporation of India) is a public service broadcaster in

the country with Akashvani (All India Radio) and Doordarshan as its two constituents. It

came into existence on 23rd November 1997, with a mandate to organize and conduct public

broadcasting services to inform, educate and entertain the public and to ensure a balanced

development of broadcasting on radio and television.

All India Radio (AIR), officially known since 1956 as Akashvani is the radio

broadcaster of India and a division of Prasar Bharati. Established in 1936,[1] it is the sister

service of Prasar Bharati's Doordarshan, the national television broadcaster. All India Radio

is one of the largest radio networks in the world. Its headquarters is at the Akashvani Bhavan

in New Delhi. Akashvani Bhavan houses the Drama Section, the FM Section and the

National Service. Doordarshan Kendra (Delhi) offices are also located on the sixth floor at

Akashvani Bhavan.

HISTORY

In British India, broadcasting began in June 1923 with programmes by the Radio Club

of Bombay and other radio clubs. According to an agreement of 1926, the private Indian

Broadcasting Company (IBC) was authorized to operate two radio stations; the Bombay

station began on 23 July 1927, and the Calcutta station followed on 26 August 1927. On 1

March 1930, however, the company went into liquidation. The government took over the

broadcasting facilities, beginning the Indian State Broadcasting Service (ISBS) on 1 April

1930 (on an experimental basis for two years, and permanently in May 1932).

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On 8 June 1936 the ISBS was renamed All India

Radio. On 1 October 1939 the External Service began

with a broadcast in Pushtu; it was intended to counter

radio propaganda from Germany directed to Afghanistan,

Iran and the Arab nations. When India became

independent in 1947 the AIR network had only six

stations (in Delhi, Bombay, Calcutta, Madras, Lucknow,

and Tiruchi); the total number of radio sets at that time

was about 275,000. On 3 October 1957 the Vividh

Bharati Service was launched, to compete with Radio

Ceylon. Television broadcasting began in Delhi in 1959

as part of AIR, but was split off from the radio network

as Doordarshan on 1 April 1976. FM broadcasting began

on 23 July 1977 in Madras, and was expanded during the

1990s.

The word "Akashvani" was coined by M. V. Gopalaswamy after setting up the

nation’s first private radio station in his residence, “Vittal Vihar” (about 200 yards from

AIR’s current location in Mysore) in 1936. Akashvani means "celestial announcement"; the

word, of Sanskrit origin, is often found in Hindu mythology. When the gods wished to say

something, an akashvani occurred. Literally, akash means "sky" and vani means "sound" or

"message". Thus, Akashwani seemed to be fit for use by a radio broadcaster and was later

adopted by All India Radio

DOMESTIC SERVICES

AIR has many services in a number of languages, each serving different regions across India.

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VIVIDH BHARATI

Vividh Bharati is one of the best-known services of AIR. Its name roughly translates

as "Multi-Indian Service", and it is also known as the Commercial Broadcasting Service

(CBS). It is the most commercially-accessible of the AIR networks and is popular in Mumbai

and other large cities. Vividh Bharati offers a wide range of programmes including news, film

music and comedy programs. It operates on different mediumwave-band frequencies for each

city.

Some programs broadcast on Vividh Bharati are:

Hawa-mahal: Radio plays based on novels and plays

Santogen ki mehfil: Comedy

Other services include:

Primary Channel (regional, 116 stations)

Local Service (86 stations)

National Channel (nighttime; launched 18 May 1988; main frequency 1566 kHz from

Nagpur

Home News Service (also via newsonair.com)

External Services in 27 languages

Yuv-vani, the Voice of Youth (launched 21 July 1969 on 1017 kHz)

FM Channels (AIR FM Rainbow – 12 stations, AIR FM Gold – 4 stations, FM

Classical Music/Amrutha Varshini)

Regional services

The headquarters of the Regional Deputy Directors General are located at Delhi and

Chandigarh (NR), Lucknow and Bhopal (CR), Guwahati (NER), Kolkata (ER), Mumbai and

Ahmedabad (WR), Chennai and Bangaluru (SR). All frequencies are in kHz, unless

otherwise noted.

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Northern regional serviceCity Frequency City Frequency City Frequency

Agra 1530 Ajmer 603 Allahabad 1026Almora 999 Barmer 1458 Bikaner 1395Chamo (Gopeshwar) 1485 Delhi A

(Indraprastha) 819 Delhi B (Rajdhani) 666

Delhi C (Vividh Bharti) 1368 Delhi D (Yuv-

vani'"0 1017 Delhi (National Channel) 1215

Diskit 1602 Drass 1485 Gorakhpur 909Jaipur A 1476 Jalandhar A 837 Jalandhar B 702Jammu A 990 Jodhpur A 531 Kalpa (Kinnaur) 1584Kargil A 684 Kargil B 1584 Khalsi 1485Kota 1413 Kupwara 1350 Leh 1053Lucknow A 747 Lucknow C 1278 Mathura 1584Najibabad 954 Naushera 1089 Nyoma 1485Padam 1589 Pauri 1602 Pithoragarh 1602Rampur 895 Rohtak 1143 Shimla 774Srinagar A 1116 Srinagar C 1224 Suratgarh 918Tiesuru 1602 Udaipur 1125 Uttarkashi 1602Varanasi A 1242

Kolkata Centre of All India Radio

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Northeast regional serviceCity Frequency City Frequency

Agartala 1269 Guwahati A 729Shillong 864 Imphal 822

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Eastern regional serviceCity Frequency City Frequency

Bhagalpur 1458, 1206 Chinsurah (National Channel, GOS, 1 MW) 1134Cuttack A 972 Darbhanga 1296Jamshedpur 1544 Kolkata A 657Kolkata B 1008 Kolkata C (Vividh Bharati) 1323Patna A 621 Ranchi A 549Kolkata (FM) 107.7 Kolkata (FM) 100.2

Western regional service

City Frequency City Frequency

Ahmedabad A 846 Aurangabad 1521

Bhopal A 1593 Chhindwara 102.2 MHz

Chhatarpur 675 Gwalior 1386

Indore A 648 Jalgaon 963

Mumbai A 1044 Mumbai B (Asmita Marathi Programme) 558

Mumbai C (Vividh Bharati) 1888 Nagpur A 585

Nagpur B (National Channel, 1 MW) 1566 Panaji A 1287

Panaji B (Vividh Bharati) 828 Pune A 792

Rajkot A 810 Ratnagiri 1143

Solapur 1602 Sangli 1251

South regional service

City Frequency City Frequency

Adilabad 1485 Bangalore A 612

Chennai A 720 Chennai C (Vividh Bharati) 730

Coimbatore 999 Gulbarga 1107

Hyderabad A 738 Hyderabad B 1377

Kozhikode A 684 Madurai 1269

Nagercoil 101 MHz Udhagamandalam 1602 (187.2m wavelength)

Port Blair 684 Thiruvananthapuram A 1161

Thiruvananthapuram 101.9 MHz Thrissur A 630

Tiruchirapalli A 936 Tirunelveli 1197

Vijayawada A 837 Visakhapatnam 927

Gautam 456 Pondicherry 1215

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EXTERNAL SERVICES

The external services of All India Radio broadcast in 27 languages to countries

outside India—primarily via high-power shortwave band broadcasts, although medium wave

is also used to reach neighbouring countries. In addition to broadcasts targeted at specific

countries by language, there is a General Overseas Service broadcasting in English with 8¼

hours of programming each day aimed at a general international audience. The external

broadcasts were begun on 1 October 1939 by the British government to counter the

propaganda of the Nazis directed at the Afghan people. The first broadcasts were in Pushto,

beamed to Afghanistan and the North-West Frontier Province. Soon broadcasts began in

other languages including Dari, Persian, Arabic, English, Burmese, Japanese, Chinese, Malay

and French. The external services broadcast in 16 foreign and 11 Indian languages, with a

total program output of 70¼ hours per day on medium- and shortwave.

External service transmitter sites

Location # of transmitters kW Frequency DRM !

Aligarh 4 250

Bengalure (SPT Bangalore) 6 500 SW DRM

Chennai (Madras) 1 100

Gorakhpur 1 50

Guwahati 1 50

Jalandhar 1 300

HPT Khampur (Delhi) 7 250

Kingsway (Delhi) 3 50

Kingsway (Delhi) 2 100

Mumbai (HPT Malad) 1 100

Panji 2 250

Tuticon 1 100

RAJKOT MW SPT 1 1000 MW DRM

Foreign languages broadcast are Arabic, Baluchi, Burmese, Chinese, Dari, English,

French, Indonesian, Nepali, Persian, Pushtu, Russian, Sinhala, Swahili, Thai and Tibetan.

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Indian languages broadcast are Bengali, Gujarati, Hindi, Kannada, Malayalam, Punjabi,

Saraiki, Sindhi, Tamil, Telugu and Urdu. The longest daily broadcast is the Urdu Service to

Pakistan, around the clock on DTH and on short- and mediumwave for 12¼ hrs. The English-

language General Overseas Service are broadcast 8¼ hours daily. During Hajj, there are

special broadcasts beamed to Saudi Arabia in Urdu. The external services of AIR are also

broadcast to Europe in DRM (Digital Radio Mondiale).

The transmissions are broadcast by high-power transmitters located at Aligarh,

Bengaluru, Chennai, Delhi, Gorakhpur, Guwahati, Mumbai and Panaji on shortwave and

from Jalandhar, Kolkata and Tuticorin on mediumwave. Some of these transmitters are

1000 kW (1 MW) or 500 kW. Programs are beamed to different parts of the world except the

Americas; however, the United Kingdom broadcast is received well there. In each language

service, the program consists of news, commentary, a press review, talks on matters of

general or cultural interest, feature programmes, documentaries and music from India and the

target region. Most programs originate at New Broadcasting House on Parliament Street in

New Delhi, with a few originating at SPT Bengaluru, Chennai, Hyderabad, Jalandhar,

Kolkata, HPT Malad Mumbai, Thiruvanthapuram and Tuticorin.

The External Services Division of AIR is a link between India and rest of the world,

especially in countries with Indian emigrants and people of Indian origin. It broadcasts the

Indian point of view on matters of national and international importance, and demonstrates

the Indian way of life through its programs. QSL cards (which are sought-after by

international radio hobbyists) are issued to radio hobbyists by AIR in New Delhi for

reception reports of their broadcasts.

Other services

News-on-phone service

All India Radio launched news-on-phone service on 25 February 1998 in New Delhi;

it now has service in Chennai, Mumbai, Hyderabad, Indore, Patna and Bangalore. The service

is accessible through STD, ISD and local calls. There are plans to establish the service in 11

more cities: Ahmedabad, Bhopal, Guwahati, Gwalior, Jabalpur, Jaipur, Kolkata, Lucknow,

Ranchi, Simla and Thiruvanthapuram. English and Hindi hourly news bulletins may be heard

live.[10] News in MP3 format may be directly played from the site, and filenames are time-

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stamped. AIR news bulletins are available in nine regional languages (Tamil, Kannada,

Gujarati, Bengali, Marathi, North East, Punjabi, Telugu and Urdu).

Direct-to-home service

Direct-to-home (DTH) service is offered on 21 channels via Insat.

Documentaries

There is a long tradition of documentary features on AIR. There is great interest in

radio documentaries, particularly in Third World countries like India, Iran, South Korea and

Malaysia. This format has been revived because of its flexibility, cost-cutting capacity,

messaging potential and creative potential with producers such as Chitra Narain, R. G. Narula

and Danish Iqbal. Iqbal has brought his experience as a drama producer to the documentary

field; his documentary "Yeh Rishta Kya Kehlata Hai" makes effective use of narrative and

ambient sounds. The documentary is a heartfelt account of an unseen bridge between a

Kashmiri, Shikarah Wala, and his auto rickshaw-driver friend in Delhi. Although they never

met, their unseen bond transcends the barriers of political, religious and regional prejudice.

Because Narula, Chitra and Danish had a long tenure at Delhi and creative collaboration with

media institutes, their influence is seminal in shaping the thinking of their colleagues. Chitra

and Narula were rewarded for their work, and Danish twice received the Public Service

Broadcasting Award for his documentaries.

Central Drama Unit

AIR's Central Drama Unit is responsible for the national broadcast of plays.

Playwrights and producers such as Chiranjeet, Satyendra Sharat, Nirmala Agarwal and

Danish Iqbal has been associated with the department. Plays produced by the CDU are

translated and produced by regional stations. Since its inception in the 1960s the unit has

produced more than 1,500 plays, and the CDU is a repository of old scripts and productions.

The National Programme of Plays is broadcast by the CDU of AIR the fourth Thursday of

each month at 9.30 pm. On the National Programme of Plays, the same play is produced in 22

Indian languages and broadcast at the same time by all regional and national network

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stations. The CDU also produces Chain Plays, half-hour dramas broadcast in succession by a

chain of stations.

Controversy

During his broadcasts from Azad Hind Radio, Subhas Chandra Bose referred to pre-

independence AIR as Anti Indian Radio. It is believed by some that the theme music for All

India Radio was composed by violinist V. G. Jog. However, it is also known that the

Czechoslovak composer Walter Kaufmann supervised the Western Music Department at AIR

during the 1930s. Although he did not compose the signature tune as such, an excerpt from

one of his sonatas (played by violinist Mehli Mehta, father of conductor Zubin Mehta) later

became the signature tune for AIR. According to other sources, the tune (played on the violin,

viola and tambura) was composed by John Foulds.

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Objectives:

The major objectives of the All India Radio are as follows:

i) To uphold the unity and integrity of the country and the values enshrined in the

Constitution.

ii) To Promot national integration.

iii) To safeguarding citizen’s rights to be informed on all matters of public interest and

presenting a fair and balanced flow of information.

iv) To pay special attention to the fields of education and spread of literacy, agriculture,

rural development, environment, health and family welfare and science and

technology.

v) To create awareness about women’s issues and taking special steps to protect the

interests of children, aged and other vulnerable sections of the society.

vi) To provide adequate coverage to the diverse cultures, sports and games and youth

affairs.

vi) To promote social justice, safeguarding the rights of working classes, minorities and

tribal communities.

vii) To promote research and expand broadcasting facilities and development in broadcast

technology.

The Board

The Board is governed, which comprises a Chairman, an Executive Member (also

known as Chief Executive Officer), a Member (Finance), a Member (Personnel), six part-

time Members, a representative of the Ministry of Information & Broadcasting and Director

General of All India

Radio and Doordarshan as ex-officio Members. The chairman is a part time member with a

six year tenure.

The executive Member, the Member (Finance) and the Member (Personnel) are whole

time member also with a six year tenure, subject to the age limit of 62 years.

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The Prasar Bharati Board meets from time to time and deliberates on important policy

issues and gives directions to the executive to implement policy guidelines.

The Members of the Board

1. Sh.M.V.Kamath Chairman

2. Shri B.S.Lalli Chief Executive Officer

3. Shri A.K.Jain Member (Finance)

4. Shri Shiva Kumar Member (Personnel)

5. Shri M.L.Mehta Part time Member

6. Smt. Chitra Mudgal Part time Member

7. Shri R.N.Bisaria Part time Member

8. Sh.George Verghese Part time Member

9. Smt.Mamta Shanker Part time Member

10. Dr.Sunil Kapoor Part time Member

11. Shri Pradeep singh (upto 19th Dec-2007) Add. Secy. Representative of the Ministry

of Information & Broadcasting

12. Sh.Uday Kr.Varma (from 20th Dec-2007) Add. Secy. Representative of the Ministry

of Information & Broadcasting

13. Shri B.S.Lalli Director General (Akashvani),

14. Sh.L.S. Mandloi Director Genral (Doordarshan)

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ORGANISATIONAL STRUCTURE

The Board functions at the apex level ensuring formulation and implementation of the

policies of the organization and fulfillment of the mandate in terms of the board. The

Executive Member functions as a Chief Executive Officer (CEO) of the Corporation subject

to the control and supervision of the Board. The CEO, the Member (Finance) and the

Member (Personnel) perform their functions out of board headquarters at 2nd Floor, PTI

Building, Parliament Street, New Delhi 110 001.

All important policy matters relating to Finance, Administration and Personnel are

submitted to the CEO and the Board through the Member (Finance) and Member (Personnel)

as required, for the purpose of advice, implementation of proposals and decisions thereon.

Officers from different streams working in the Prasar Bharati Secretariat assist the CEO,

Member (Finance) and Member (Personnel) in integrating actions, operations, plans and

policy implementation as well as to look after the budget, accounts and general financial

matters of the Corporation. Prasar Bharati also has a unified vigilance set up at the

headquarters, headed by a Chief Vigilance Officer.

Prasar Bharati Marketing offices located at Mumbai, New Delhi, Kolkata, Chennai,

Bangalore, Hyderabad, Trivendrum and Guwahati look after all marketing activities of both

All India Radio and Doordarshan. There is a branch Marketing office located at Kochi also.

To facilitate decision making, the Policy & Executive Committee (earlier known as

Management Committee) has been constituted for both Doordarshan and AIR, chaired by the

CEO.

The Directorate General of All India Radio and the Directorate General of

Doordarshan are headed by the Directors General. They function in close association with the

Member (Finance) and Member (Personnel) and the CEO in carrying out the day-to-day

affairs of AIR and Doordarshan. Both in AIR and Doordarshan, there are broadly four

different Wings responsible for distinct activities viz. Programme, Engineering,

Administration & Finance and News.

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PROGRAMME WING

The Deputy Directors General (DDGs) in the headquarters and in the regions look

after all matters relating to programming and content creation. These officers belong to the

Programme cadre of All India Radio. The offices of the regional DDGs are located at Delhi

and Chandigarh (Northern Region), Mumbai and Ahmedabad (Western Region), Lucknow

and Bhopal (Central Region), Kolkata (Eastern Region), Guwahati (North Eastern Region),

Chennai (Southern Region –I) & Bangalore (Southern Region-II) .

AUDIENCE RESEARCH WING

There is a Director (Audience Research) to assist the Director General in carrying out

surveys on the programmes broadcast by various stations of All India Radio. Audience

Research Unit of DG:AIR is supported by six Dy.Directors at the Regional Mobile Units

located at Shillong, Kolkata, Chennai, Mumbai, Delhi and Allahabad and 38 Audience

Research Units headed by Audience Research Officers spread over the entire country. This is

perhaps the largest media research organisation in the world.

ENGINEERING WING

Engineer-in-Chief, All India Radio is the Engineering Head of AIR network, assisted

by Chief Engineers. He is responsible for planning, design, operation & maintenance of the

total technical infrastructure of AIR including the radio broadcast development. E-in-C

operates through the Engineering Headquarters, Planning & Development Unit in the AIR

Directorate, Zonal Chief Engineers and Engineering, Heads of various AIR stations. The

Zonal Chief Engineers offices are located at Mumbai, Kolkata, Guwahati, Chennai and New

Delhi. E-in-C is also responsible for radio broadcast, research & development and training of

engineering staff.

The Civil Construction Wing (CCW), also headed by a Chief Engineer, looks after the civil

construction activities.

The CCW also caters to the needs of Doordarshan.

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ADMINISTRATIVE WING

A Deputy Director General (Administration) assists the Director General on all

matters of general administration. A Director looks after the Engineering and Programme

administration of All India Radio.

NEWS SERVICES DIVISION

The News Services Division works round the clock and broadcasts 511 bulletins daily

both in the home and external services, headed by a Director General (News). There are 44

Regional News Units and one Central News Unit of News Services Division of AIR.

EXTERNAL SERVICES DIVISION

The External Services Division of All India Radio broadcasts in 26 languages – 16

foreign and 10 Indian languages. These services are radiated for an aggregate duration of 72

hours daily and are projected to cover 100 countries.

TRANSCRIPTION & PRO-GRAMME EXCHANGE SERVICE

The Transcription and Programme Exchange Service, headed by a Director, looks

after exchange of programme among stations, building and maintenance of sound archives

and marketing of select archival recordings. It also looks after the marketing of archival tapes

and CDs.

RESEARCH & DEVELOPMENT WING

The functions of the Research Wing include Research and Development of equipment

required by AIR and Doordarshan, investigation and studies relating to AIR and

Doordarshan. It is also responsible for development of prototype models of R&D equipment

for limited use field trials in the network of AIR and Doordarshan. A Chief Engineer heads

the R&D Wing.

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STAFF TRAINING INSTITUTE (PROGRAMME)

The Staff Training Institute (Porgramme) functions at Kingsway Camp, Delhi. It

imparts in-service training to Programme Personnel and Administrative Staff and induction

course for the newly recruited staff and short duration refresher courses. There is another

Staff Training Institute (Programmes) functioning at Bhubaneshwar. In addition, at present

five Regional Training Institutes at Hyderabad, Shillong, Lucknow, Ahmedabad and

Thiruvananthapuram are working.

STAFF TRAINING INSTITUTE (TECHNICAL)

The Staff Training Institute (Technical), part of the Directorate since 1985, now

functions at Kingsway Camp, Delhi as a Subordinate Office of AIR. The Institute organizes

Training Courses for the engineering staff of All India Radio and Doordarshan from the level

of Technician to the Superintending Engineer. It also conducts Departmental Qualifying and

Competitive Examinations. There is one Regional Staff Training Institute (Technical)

at Bhubaneswar.

RADIO STATIONS

There are at present 231 Radio Stations. Each of these radio stations functions as the

subordinate office of All India Radio.

HIGHPOWER TRANSMITTERS

These stations are equipped with short wave/medium wave transmitters altogether

eight extensive aerial system to serve the external, home and news services of All India

Radio.The main function of these centers is to transmit the programmes produced at nearby

studios and also from Delhi studios.

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SECURITY AT AIR

A Deputy Director General (Security) assisted by Assistant Director General

(Security) looks after security and safety of AIR installations, transmitters, studios, offices,

etc. These officers also look after the security needs.

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RAW MATERIALS

Today's radio consists of an antenna, printed circuit board, resistors, capacitors, coils

and transformers, transistors, integrated circuits, and a speaker. All of these parts are

housed in a plastic case.

An internal antenna consists of small-diameter insulated copper wire wound around a

ferrite core. An external antenna consists of several aluminum tubes that slide within

one another.

The printed circuit board consists of a copper-clad pattern cemented to a phenolic

board. The copper pattern is the wiring from component to component. It replaces

most of the wiring used in earlier radios.

Resistors limit the flow of electricity. They consist of a carbon film deposited on a

cylindrical substrate, encased in a plastic (alkyd polyester) housing, with wire leads

made of copper.

Capacitors store an electrical charge and allow alternating current to flow through an

electrical circuit but prevent direct current from flowing in the same circuit. Fixed

capacitors consist of two extended aluminum foil electrodes insulated by

polypropylene

film, housed in a plastic or ceramic housing with copper wire leads. Variable

capacitors

have a set of fixed aluminum platesand a set of rotating aluminum plates with an air

insulator.

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Coils and transformers perform similar functions. Their purpose is to insulate a circuit

while transferring energy from one circuit to another. They consist of two or more sets

of copper wire coils either wound on an insulator or mounted side-by—side with air as

the insulator.

Transistors consist of germanium or silicon encased in a metal housing with copper

wire leads. The transistor controls the flow of electricity in a circuit. Transistors

replaced vacuum tubes used in earlier radios.

The integrated circuit houses thousands of resistors, capacitors, and transistors into a

small and compact package called a chip. This chip is about the size of the nail on the

little finger. The chip is mounted in a plastic case with aluminum tabs that allow it to

be mounted to a printed circuit board.

DESIGN

Radios consist of many specialized electronic circuits designed to perform specific

tasks-radio frequency amplifier, mixer, variable frequency oscillator, intermediate

frequency amplifier, detector, and audio amplifier.

The radio frequency amplifier is designed to amplify the signal from a radio broadcast

transmitter. The mixer takes the radio signal and combines it with another signal

produced by the radio's variable frequency oscillator to produce an intermediate

frequency. The variable frequency oscillator is the tuning knob on the radio. The

produced intermediate frequency is amplified by the intermediate frequency amplifier.

This intermediate signal is sent to the detector which converts the radio signal to an

audio signal. The audio amplifier amplifies the audio signal and sends it to the speaker

or earphones.

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The simplest AM / FM radio will have all of these circuits mounted on a single

circuit board. Most of these circuits can be contained in a single integrated circuit. The

volume control (a variable resistor), tuning knob (a variable capacitor), speaker,

antenna, and batteries can be mounted either on the printed circuit board or in the

radio's case.

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THE MANUFACTURING PROCESS

There is no single process for manufacturing a radio. The manufacturing process

depends upon the design and complexity of the radio.

An example of a standard AM/FM radio.

The simplest radio has a single circuit board housed in a plastic case. The most

complex radio has many circuit boards or modules housed in aluminum case.

Manufacturers purchase the basic components such as resistors, capacitors, transistors,

integrated circuits, etc., from vendors and suppliers. The printed circuit boards,

usually proprietary, may be manufactured in house. Many times, manufacturers will

purchase complete radio modules from an vendor. Most of the manufacturing

operations are performed by robots. These include the printed circuit boards and

mounting of the components on the printed circuit board. Mounting of the printed

circuit board and controls into the case and some soldering operations are usually

done by hand.

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1. The blank printed circuit board consists of a glass epoxy resin with a thin

copper film cemented to one or both sides. A light sensitive photoresist film is

placed over the copper film. A mask containing the electrical circuitry is placed

over the photoresist film. The photoresist film is exposed to ultraviolet light.

The photoresist image is developed, transferring the image to the copper film.

The unexposed areas dissolve during etching and produce a printed circuit on

the board.

2. Holes are drilled in designated locations on the printed circuit board to accept

the components. Then, the board is pre-soldered by dipping it in a bath of hot

solder.

3. Smaller electronic components such as resistors, capacitors, transistors,

integrated circuits, and coils are installed in their designated holes on the

printed circuit board and soldered to the board. These operations can be

performed by hand or by robots.

4. Larger components such as power transformer, speaker, and antenna are

mounted either on the PCB or cabinet with screws or metal spring tabs.

5. The case that houses the radio can be made either of plastic or aluminum.

Plastic cases are made from pellets that are melted and injected into a mold.

Aluminum cases are stamped into shape from sheet aluminum by a metal press.

6. External components not mounted on the printed circuit board can be the

antenna, speaker, power transformer, volume, and frequency controls are

mounted in the case with either screws, rivets, or plastic snaps. The printed

circuit board is then mounted in the case with screws or snaps. The external

components are connected and soldered to the printed circuit board with

insulated wires made of copper and plastic insulation.

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BROADCASTING

The hard disk based system facilities the following for transmission of programmes :

Broadcasting from library list-select and play

Instant start of sound elements by assignable hot keys.

Data base access for information retrieval, search or entry function.

Rearrangements of list.

ON – AIR WORKSTATION

To ensure smooth and uninterrupted programme transmission one of the work

stationsis designated as ‘On-air ’Workstations.  This provides 4-5 hrs stand-alone

service.Functions of on-air workstation :

Loading and controlling the play out of a scheduled play list in assisted

or automated mode.

Modifying a play list during  play back, inserting, deleting or adding items of

the play list.

Accessing text and information attached to play list, tens.

Pre-listening and receiving play list source items.

Searching new items and inserting them instantly.

Loading and playing items to a secondary list.

Operation of secondary equipment through a relay interface unit.

Time and status information of services – ready to play, on-air, not cued etc.

OPERATIONAL SAFETY

The hard disk based system is equally prone to the problems occurring in a

computer. Hence, in case of any problem in the system or total failure of the

system, the stored data should be safe.  For this purpose, the following

arrangements have been done :-

Mirroring of hard disks and RAID for data recovery.27

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Duplexing of servers in back to back configuration.

Automated back up.

Buffering in play out stations.

Back up routers/switchers.

Any studio can function as an instant back up, in case of a hardware failure

inone studio.

RAID-Redundant Array of Inexpressive Disc.

SCSI- Small Computer System Interface.

CPU- Central Processing Unit

The signal downlink frequency IS 4000M OR 4GHZ

Satellite consists of solar planets

Solar planets are used to give power to the satellite

The FM radio signal is transmitted coverage area is 70 m

Doordarshan is coverage area is 30m in channel11

The FM radio signal strength is 103.1MHZ

In this frequency the FM is activated

DIFFERENT SATELLITES & USES:

Insat 3C DD National Polarisation –Vertical Sig. rate is fs=6250MHZ

Insat 3A Saptagiri Polarisation—Vertical Sig. rate is fs=6250MHZ

Insat 4B National (Hyd) fs=10990MHZ Sig. rate 27500

Insat 4B Telugu Programme frequency 11070MHZ Sym rate 27500

The transmitted signal is connected to “Audio, Video switching unit”.

In this monitor & program control units are present.

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The voltage signal O/ps and current signal O/p signals are connected to “Manual Patch

Panel”

Manual Patch Panel

Audio & Video Switch

Programming Amp

Pattern Generator

TV

AUDIO & VIDEO SWITCHING

In this modulators are present because of modulates the audio signals & video signals are

modulated by using vision modulator.

In this pulse switch modulation is used to modulate audio & video signals

PROGRAMMING AMPLIFIER:

In this set of boxes are placed.

The programming amplifiers are separated to audio & video.

Audio Programming amplifier is variable resistor.

By using this we can change the frequency and its range

Video signal is amplified by using stap amplifier

In this amplifier, the signal is amplified by using stap.

The amplitude of video signal is IV(P-P)

EXCITER:

Exciter

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Driver unit

Power amplifiers

Combiner

Feeder

Dummy load

o/p

It consist of SMPS because the prog. Amp o/o is ac signal but it does not allow the ac. The ac

signal is coverted to dc signal by using SMPS.

Signal frequency in exciter is RF

The o/ps of exciters are connected to driver unit.

DRIVER UNIT:

It consists of attenuator

The i/p of driver unit is Radio frequency signal

The driver unit & exciter units both are coupled to each other.

The o/p of driver unit is connected to power amplifiers

POWER AMPLIFIERS:

It consists of 2 power amplifiers for to amplify the signal strength or power to weak audio &

video signals

Each amplifier contained 50watts power

Then the total power 100w

The power amplifier unit also contain fans for cooling at 230v.

COMBINE UNIT:

In this unit the left power amplifier and right side power amplifier o/ps signals are combined

to each other.

The o/p of this unit is connected to dummy load.30

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DUMMY LOAD:

It is pure resistor

In this required power is 5KW

In this copper tube are used to transmit the signal

Its o/p is 3 phases

The o/p signal is connected to feeder at 5KW power is in the o/p signal.

If you get problem in transmitting, we can solve that problem by using this unit.

FEEDER:

Feeder is a middle part of dish.

In this set of boxes are present in feeder

It is set to dish at particular frequency

The o/p signal is connected to dish and radiates the signal.

The signal is received by receiving antenna.

RECEIVER UNIT:

Received Antenna

Source Unit

Master

Limiter

Remote Station

TV

SOURCE UNIT:

It consists of several variable resistors

In this unit fading is applied to signals & is connected to master

The o/p signal is audio & video.

The master consists of limiter

It is only for audio.

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In the a/c planet indication is presented.

A/c planet indication

Blower Compressor

REMOTE STATION:

It is attenuator

The signal strength is 17-20db

By using this unit we can select the same particulars channel at tuned frequency.

The FM is tuned at 103.1MHZ

Doordharshan 217.239584MHZ

In this II-Channel & III-Band are used in radio station.

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