4.1.1 Diodes
 

• Diode symbols;Diode characteristics and properties;Diodes in series and parallel;Main characteristics and use of silicon controlled rectifiers (thyristors), light emitting diode, photo conductive diode, varistor, rectifier diodes;Functional testing of diodes Materials, electron configuration, electrical properties;P and N type materials: effects of impurities on conduction, majority and minority characters; PN junction in a semiconductor, development of a potential across a PN junction in unbiased, forward biased and reverse biased conditions;Diode parameters: peak inverse voltage, maximum forward current, temperature, frequency,leakage current, power dissipation;Operation and function of diodes in the following circuits: clippers, clampers, full and half wave rectifiers, bridge rectifiers, voltage doublers and triplers;Detailed operation and characteristics of the following devices: silicon controlled rectifier(thyristor),light emitting diode, Shottky diode,photocondiuctive diode, varactor diode, varistor,rectifier diodes, Zener diode

4.1.2 Transistors

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  • Transistor symbols;Component description and orientation; Transistor characteristics and properties Construction and operation of PNP and NPN transistors;Base, collector and emitter configurations:Testing of transistors;Basic appreciation of other transistor types and their uses;Application of transistors: classes of amplifier (A,B, C);Simple circuits including: bias, decoupling, feedback and stabilization;Multistage circuit principles: cascades, push-pull, oscillators, multivibrators, flip-flop circuits 4.1.3 Integrated Circuits Description and operation of logic circuits and linear circuits / operational amplifiers Description and operation of logic circuits and linear circuits; Introduction to operation and function of an operational amplifier used as: integrator, differentiator,voltage follower, comparator;Operation and amplifier stages connecting methods:resistive capacitive, inductive (transformer),inductive resistive (IR), direct;Advantages and disadvantages of positive and negative feedback

• 4.2 Printed Circuit Boards
  • Description and use of printed circuit boards

• 4.3 Servomechanisms
  • Understanding of the following terms: Open and closed loop systems, feedback, follow up, analog transducers;Principles of operation and use of the following synchro system components / features: resolvers, differential ,control and torque, transformers, inductance and capacitance transmitters Understanding of the following terms: Open and closed loop, follow up, servomechanism, analogue, transducer,null, damping, feedback, deadband; Construction operation and use of the following synchro system components: resolvers, differential, control and torque, E and I transformers, inductance transmitters, capacitance transmitters, synchronous transmitters; Servomechanism defects, reversal of synchro leads, hunting