SYLLABUS FOR DEPARTMENTAL EXAMINATION [Revised - 1999]

(for promotion of Senior Technicians etc. to the grade of Engineering Assistants)

PART I - BASIC PRINCIPLES OF ELECTRICITY AND ELECTRONICS

Basic Electricity:

Concepts of current, voltage, power and energy, units of currents, voltage, power and energy, concepts of DC and AC - their differences, amplitude and frequency in AC, peak, average, instantaneous and RMS values, Ohm's law and its applications.

A.C Circuits. :

Phase - Phase relationship between voltage and current in pure resistive, capacitive and inductive circuits, Active and reactive power - Physical concepts, power factor and correction of P.F, Poly-phase circuits, phase sequence, 3 phase circuits - Star and Delta connections, relationship between line and phase voltages and current, Power in single phase and 3-phase circuits, Balancing 3-phase circuits and its importance.

Electrical Wiring :

Electrical symbols, Standard wire gauge, types of conductors and insulators, switches and fuses, cabling, practices, earthing principles, circuit breaker (ACB and OCB), conduit wiring, power supply layout, meters and measuring instruments, CT's and PT's, Precautions in the use of CT.

Storage Batteries :

Different types of storage batteries, capacity and rating of batteries, Methods of charging, trickle charging, battery care and maintenance.

Components :

Different types of resistance, inductance and capacitance and their uses, Resistance, reactance and impedance. Current, voltage and power ratings, Non-inductive resistors.

RLC Circuits :

Colour codes for marking of resistors and capacitors, R, L and C-Series and parallel resonance circuits and their properties and uses - Resonance frequency, Q and Bandwidth concepts, Tuning and damping.

Electrical Machines :

(a) Basic idea of DC motors, particularly as used in ultra portable tape recorders and cassette recorders. Speed variations their causes. Types of AC Motors. Simple ideas of single and 3-phase motors - Induction, Synchronous. Rating of a motor (HP of a motor)- Starters for motors, speed change in motors, basic maintenance of motor, losses and efficiency of motors.
(b) General principles of working of a transformer, turns ratio, Primary, secondary and tertiary windings, tappings on windings, terminal leads and insulators. Losses and efficiency, Magnetic cores and their properties. Oil and natural cooling capacity of a transformer, single phase and 3-phase transformers, transformers for 50 Hz AC Power Voltage Regulator, parallel operation and load sharing, basic ideas of maintenance of these machines. Oil testing and filtration.

Generators :

AC generators, Relationship between speed, frequency and voltage generated capacity. Single and 3-phase generators, Simple ideas of prime-movers, Petrol and diesel generators, operating principles and differences between the two, fuel oils, fuel pumps, cylinders, Piston and Piston rings, Governors and regulators, paralleling of the two generators - General ideas of maintenance of generators. Brushless excitation in Diesel Generators.

Safety Regulations:

Safety precautions, Fire fighting and First-aid including artificial respiration as detailed in the AIR "Manual of Safety Precautions".

Electronics :

The general principles of working of diodes, triodes, tetrodes and pentodes. Applications of vacuum tubes, concepts of rp. gm and m and their inter-relationship. Gas discharge tubes, gas diodes and thyratrons, their characteristics and uses. Conductors, semi-conductors and insulators. Doping, P.N. Semi conductors, simple ideas of current through such devices. Effect of temperature on semi-conductors, forward and reverse biasing of a P-N junction - PNP and NPN transistors. Zener diodes and their characteristics and applications. General ideas of FET, SCR, photo diodes and photo transistors. Varactor diode and its application, operational amplifiers, Digital basic, Logic gates and Digital numbering system.

Earthing Systems :

Concept of earthing. Different types of earthing. Earth pits. Measurement of earth resistance.

Semi-Conductors Circuitry :

The three configurations of transistor amplifiers, comparison with valve circuits characteristics, biasing methods and stabilisation. Transistor as an amplifier - voltage gain and power gain, input and output impedance in the three configurations.

Amplifiers and Oscillators :

Amplifier - Classifications and their characteristics, feedback in amplifiers - positive and negative feedback. Oscillators - different types, general ideas of their characteristics and uses : VCO and concept of PLL

Rectification:

Full and half wave rectifiers, Peak Inverse Voltage and its significance, filters, regulated power supplies including SMPS and CVT

Wave Filters:

Low pass, high pass, band pass and band reject filters, general ideas, their characteristics and applications.

Antenna:

Basic ideas of Antennas in medium wave, short wave and VHF range - their directional pattern and impedance.

Basic Concept of Satellite communication

PART II-A SOUND BROADCASTING

1. Sound Broadcasting - Basics :

   • Basic concepts of broadcast chain from microphone to antenna - Block diagrams and level diagrams of studio chain and working principles of various functional blocks, like pre-amplifier, programme and line amplifier, concept of level of programme and its control - Use of V.U. meters, Multiple pads, Repeat coils.
   • Different types of microphones used in the studio. Proper use and care of microphones. Impedances, sensitivity and directivity patterns for practical applications.
   • Different types of loud-speakers-their directivity, sensitivity and frequency response. Impedance characteristics. Power handling capacity. Loudspeaker for high quality monitoring.
   • Working principles of Turn Table, CTR, R-DAT, CD Players.
   • Faders and mixers in mixing console and their characteristics.
   • Typical set-up for an outside broadcast programme and special precautions to be taken. Types of microphones to be used. OB amplifiers and their working principles. Programme and communication linkage from OB spot to control-room.

1. A.M. Reception :

   Super-heterodyne receivers. Block schematic of an A.M. communication receiver - general ideas of working of each stage, sensitivity, selectivity, fidelity and AGC - (Alignment of a receiver). Different types of receiving aerials - dipole, cage, inverted L-type, Rhombic and their directivity consideration. (Diversity reception) -identifying noise, interference, zero-beat, heterodyne; fading etc. on received signals - reception reports. (Basic receiver servicing methods and equipment.)

2. Magnetic Tape Recording :

   Magnetic Tape-Biasing, De-magnetization, Play-back losses, properties of magnetic tape recording and play back heads, erase head, gap dimensions, tape transport, wow and flutter, amplifier system, frequency compensation and equalization, line up procedures for recording, use and care of tape recorders, recording tapes and standard test tapes.

   • Transmitter and Antennas

     1. Sound Transmitters:
        • Block diagram of typical A.M. medium wave and short wave transmitters - working principles of various stages - tuning of RF stages - transmitter line up. A.M. modulation and wave forms, basic maintenance, transmitting valves - their care and testing.
        • M.W. and S.W antennas, insulators in antennas installation, protection against sparking and lightning, working on masts.
        • FM Transmitter, FM demodulation, AM/FM comparison, FM Antenna, Pre-emphasis, De-emphasis, FM Limiter.
     2. Different types of feeder lines - characteristic impedance - measurement of standing wave ratios.
     3. Antenna tuning units for MW - matching in SW - Earth radial systems.
     4. Mast lighting.

   • Satellite Broadcasting

     R.N. Terminal, up-link and down link chains and parabolic antenna system.

   • Maintenance and Measurement

     Basic ideas of distortion and noise levels - decibel notation - dB, dBm and VU. Basic ideas of measurement of frequency response, distortion and noise level in broadcast equipment. General ideas on maintenance of various equipment and maintenance schedule.

   • Air-conditioning Plants:

     Dry bulb, wet bulb temperature and relative humidity. Significance of tonnage in an AC plant, evaporator, compressor, condenser and liquid receiver and their working principles - functioning of solenoid valve and thermostatic expansion valve - procedure for charging gas and purging, air-leak detection - basic routine maintenance of AC plants - use of instruments, like anemometer, halide detector. Requirements of sound insulation and methods to achieve comfort conditions in the studio.

PART II-B T.V. BROADCASTING

1. TV Broadcasting - Basic:

   •  
      
     TV systems, - block diagram of studio chain and transmitter chain, TV standards, Scanning process, video signal, impairment of picture due to incorrect frequency response, camera tubes and their operating principles. TV camera chain, Lenses, camera control units, monitors, video switchers. Line-up procedure of a TV studio set up for recording and transmission.
     • Video amplifiers - their band width consideration - D.C coupling and its effect on picture brightness, TV Monitors.
     • Basic principles of lighting (artists and sets) in a TV studio - light dimmers, light levels needed in a TV programmes.
     • Basic ideas of colour TV signal - lighting requirement as compared to black and white.
     • Basic principles of video tape recording and operating controls, care in handling and storage of video tapes. Various video formats.
     • Principles of operation of a Telecine chain, multi-plexer and practical adjustments in a telecine projector.
     • Facilities in a TV O.B. van, layout of cables for audio, video, power supply and microwave links in a typical OB, placement of cameras and microphones for important sports and games, ENG equipment.

     • TV transmitters VHF/UHF

       Block schematic of video and audio sections and operating principles - I.F. modulation - diplexers - VHF antennas - block schematic operating and pre-set controls - testing and alignment - synchronising circuits - FM sound systems. Salient features of BEL mark III and solid state TV transmitters in TV network. Transmitter measurements.

     • TV Receivers :

       Working principles - basic servicing procedures for TV receivers and equipment needed, deflection circuits, picture tubes, remote operation. Concept of baluns.

     • Satellite Communication:

       Block diagram of satellite transponder, uplink and down link chains, TV TRACT, S-Band & C Band TVRO system and PDAs.

     • Air-conditioning Plants :

       Dry bulb, wet bulb temperature and relative humidity. Significance of tonnage in an AC Plant, evaporator, compressor, condenser and liquid receiver and their working principles - functioning of solenoid valve and thermostatic expansion valve - -procedure for charging gas and purging air-leak detection - basic routine maintenance of AC plants and use of instruments, like anemometer, halide detector, requirements and sound insulation and methods to achieve comfort conditions in the studio.

SYLLABUS FOR DEPARTMENTAL EXAMINATION [Revised - 1999] 
(for promotion of Helper to the grade of Technician) 




Paper : I   Electrical, Diesel Generator, air-conditioning etc. 

Concepts of voltage, Current, Power Energy and their units. 
Ohms law and its applications. 

Identification & functioning of components like resistors, 
inductors, capacitors and their colour codes.  Voltage and power
ratings, series and parallel combination of components. 

Different types of batteries, their charging, trickle 
charging, care and maintenance.  Solar cells/panels.

DC supply, AC single phase and three phase supply,
regulation, power factor.

Electrical symbols, standard wire gauge, fuses,
switch-gears, earthing practices domestic wiring, 
meters like standard voltmeters. Ammeters,multi-meters,
meggers etc. 

Functioning of AC and DC motors, starters for motors,
Star/Delta connection. Speed  regulation, rating of motors
and basic maintenance.

Working of transformers, turns ratio, Primary/Secondary
voltage, tappings on windings, transformer cooling,
transformer oil testing and its filtering.

Petrol and diesel generators their working principles;
functions of various components and maintenance. 

Identification of components and functioning details in
respect of air-conditioning plants including windows 
air-conditioners; Charging of gas, leak detection and purging. 

Safety precautions, fire fighting and first aid practices
as given in AIR Manual of Safety precautions





Paper II -  Electronics and Communication Engineering. 

Identification and basics of active elements like various
types of vacuum tubes, semi conductor devices and transistors.
Circuit configurations of transistors and comparison with valve circuits.
Basics of  FET, SMPS  and digital basics.

Concept of dB, dBm, VU; Frequency Response; Distortion
and Noise Level.

Attenuators, pads, multiple pads, repeat coils, Equalisers
and filters.

Different types of Amplifiers, Rectifiers, Oscillators their
characteristics and application.

Different type of microphones and their applications.

Broadcast chain from microphone to studio output including
Announcer console pre-amplifier, Programme Amplifier,
Switching Console, Equalising Line Amplifier etc.
Maintenance of studio equipment. 

Knowledge of control of programmes in terms of level
and quality, monitoring devices such as : VU meter,
headphone, loudspeaker, Monitoring amplifier etc.

Basic of Audio/Video Tape Recorders

Outside broadcast set up; tools, equipment and precautions. 

Broadcast chain for AIR transmitter from  input to antenna at
transmitter site. Functions of important components and stages
like limiter, AF stages, RF stages etc and other ancilliary equipments.

FM transmitter and  its associated equipments. 

Various types of aerials and feeders used in AIR and Doordarshan.
Their characteristics and functions.

Basics  of Satellite communication, Radio Networking Terminal,
TVRO and DRS. 

Working knowledge of studio chain in TV studio from camera to
studio output.

Basic principles of lighting in TV studio. Care and handling of
lighting equipment.

Facilities in TV OB Van, laying cables for audio/ video, power
supply and microwave links. Handling and care of ENG and EFP equipments
and other studio  equipments.

Broadcast chain for TV transmitter from input to antenna.
Functions of important units of Low Power Transmitters (LPTs/VLPTs),
Medium Power and High Power Transmitters, (VHF/UHF), studio transmitter
link and receiving equipment.

Servicing procedures for Radio and TV receiver, tools and equipments
used for servicing. 





Paper III : Practical Test. 

Testing of skills in 

Soldering
Care & use of various mechanical and electrical tools used in
our networks.
Operation, maintenance and routine measurements on air
conditioning plants. 
Operation and maintenance of Diesel Generators. 
Electrical wiring, replacement of switches, fuses and
other components. 
Use of various meters like multimeter, sling Psychrometer,
Tachometer, hydrometer, Anemometer,Halide leak detector and
various pressure gauges.
Use of Test instruments such as insulation tester,
Transistor tester and IC tester & Oscilloscope.
Dismantling and assembling of electrical/electronic
equipment.
Maintenance of lead storage batteries.
Use of fire fighting equipment and safety gadgets.
Ability to read technical pamphlets. 

                        MODEL QUESTION FOR SR. TECH. TO EA - 2006
► Senior Technician to Engineering Assistant Paper Year 2005 downloadable 
► Senior Technician to Engineering Assistant Paper Year 2006 downloadable