Q4 now

Q4-31) Conventional flow of current in an N-P-N transistor is  - INDICATED BY

THE ARROW2) The transistor amplifier configuration which gives 180 degree phase shift

is the – COMMON EMITTER3) What are the bias  arrangements when a P-N-P transistor is used in the

common emitter configuration – THE BASE IS NEGATIVE TO THE EMITTER

4) The connections to the F.E.T. are – DRAIN, SOURCE, GATE5) The emitter follower has the following characteristics – VOLTAGE GAIN

LOW, INPUT IMPEDANCE HIGH, OUTPUT IMPEDANCE LOW

Q4-131) For an electron to move from one level to another, there must be – A

VACANT POSITION INTO WHICH IT CAN MOVE2) The unit used for energy level is – THE AMPERE HOUR3) The orbits taken by electrons are energy levels. An electron in the K shell

will have – LESS ENERGY THEN THE L,M,N SHELL4) The maximum number of electrons K-shell can contain is   - 2

ELECTRONS5) Electrons in an atom orbit the nucleus in shells, the one nearest the

nucleus is called – K SHELL

Q4-231) What are the majority carriers in an N-type semiconductor? –

ELECTRONS2) What is the purpose of a PN junction diode? – TO CONVERT AC TO

DC3) In reference to the schematic symbol for a diode, do electrons flow toward

or away from the arrow? – toward the arrow4) What type of PN diode is formed by using a fine metal wire and a section

of N-type semiconductor material? – POINT CONTACT5) What are the majority carriers in a P-type semiconductor? – HOLES

Q4-331) What are the three most common methods of interconnections? –

CONVENTIONAL PRINTED CIRCUIT BOARDS, MULTYLAYER PCB, AND MODULAR ASSEMBLIES

2) What are the three most common methods of interconnections on printed circuit boards? – CLEARANCE HOLE, PLATED-THROUGH HOLE, AND LAYER BUILD-UP

3) What is one of the major disadvantages of multilayer printed circuit boards?- DIFFICULTY OF REPAIR OF INTERNAL CONNECTIONS

4) What was the earliest form of micromodule? – CORDWOOD MODULES5) Resistors, capacitors, transistors, and the like, are what level of

packaging?- LEVEL 0

Q4-43

1) The diagrams represent – FIELD EFFECT TRANSISTOR2) The right diagram represents – FET symbol commonly used in digital

circuit where source (S) and drain (D) terminals are not specified3) The left diagram represents  - a P-channel J_FET4) The centre diagram represents    - an N-channel J-FET5) Connectors of a FET are – source, drain and gate

Q4-531) What are the two general classifications of synchro systems – TORQUE

AND CONTROL2) Describe the zero-position of a synchro transmitter. S2=top , S1=120dgr,

S3=240dgr B- THE TRANSMITTER IS IN ITS ZERO POSITION WHEN THE ROTOR IS ALIGNED WITH THE S2 STATOR WINDING

3) The 'null' point on a control synchro is when the two rotors are – 90 DEGREE APART

4) What is the physical difference between a synchro transmitter and a synchro receiver   - A SYNCHRO RECEIVER USES SOME FORM OF DAMPING TO RETARD EXCESSIVE OSCILLATIONS OR SPINNING

5) What method is used to prevent oscillations in large synchro units   - MECHANICAL DAMPING

Q4-631) A servo system with transient negative velocity feedback – IS DAMPED

WITH LITTLE VELOCITY LAG2) To reverse the direction of rotation of a two phase induction motor –

REVERSE THE POLARITY OF THE CONTROL PHASE3) In a rate servo (speed control) the signal into the servo amplifier is   -

INPUT VOLTAGE MINUS TACHOGENERATOR OUTPUT4) Loss of DC to a servo amplifier causes the motor to    - STOP5) Avalanche breakdown occurs when  - REVERSE BIAS EXCEEDS A

CERTAIN VALUE

Q4-731) A MOSFET has the advantage over a FET in that it – HAS A VERY

HIGH INPUT IMPEDANCE2) By convention IC connections are labled – PIN NUMBER ONE IS AT

THE TOP LEFT OF A NOTCH AND ARE NUMBERED ANTICLOCKWISE

3) PCB's are most likely damaged by   - REPEATED SOLDERING AND DE-SOLDERING

4) A glass fibre and epoxy based PCB base material may be identified by which colour   - GREEN

5) One of the most commonly used linear IC is the   - OPERATIONAL AMPLIFIER

Q4-4

1) A diode connected accross a relay coil is used to – DISSIPATED COIL EMF ON SWITCH OFF

2) An operational amplifier has  - HIGH GAIN, HIGH INPUT IMPEDANCE, LOW OUTPUT IMPEDANCE

3) What are the bias  arrangements when a P-N-P transistor is used in the common emitter configuration – THE BASE IS NEGATIVE TO THE EMITTER

4) The connections to the F.E.T. are  - DRAIN, SOURCE, AND GATE5) The emitter follower has the following characteristics – VOLTAGE GAIN

LOW, INPUT IMPEDANCE HIGH, OUTPUT IMPENDACE LOW

Q4-14

1) The diagram represents a – FIELD EFFECT TRANSISTOR2) Connections are – SOURCE, DRAIN , GATE3) Left diagram represents  - A P-CHANNEL4) Right diagram represents – an N-CHANNEL5) A P-Channel arrow points  - out

Q4-241) Conduction in which type of semiconductor material is similar to

conduction in a copper wire? – N-TYPE MATERIAL2) What is the name of the area in a PN junction that has a shortage of

electrons and holes? – DEPLETION REGION3) In order to reverse bias in a PN junction, what terminal of a battery is

connected to the P material? – NEGATIVE4) What type of bias opposes the PN junction barrier? – FORWARD5) What is a load? – ANY DEVICE THAT DRAWS THE CURRENT

Q4-341) Define integrated circuit – elements inseparably associated and formed in

or on a single substrate2) What are the three major types of integrated circuits? – MONOLITHIC,

FILM, AND HYBRID3) How do monolithic ICs differ from film ICs? – MONOLITHIC ICs

CONTAIN ACTIVE AND PASSIVE ELEMENTS. FILM ICs CONTAIN ONLY PASSIVE ELEMENTS

4) What is a hybrid IC? – COMBINATION OF MONOLITHIC AND FILM COMPONENTS

5) How many logic gates could be contained in LSI? – 1000 TO 2000

Q4-44

1) In the figure shown, 2 represents the – BASE OF PNP TRANSISTOR2) In a forward biased pn junction, the electrons – FLOW FROM N TO P3) A varactor diode acts like a variable – CAPACITANCE4) Zener diodes are normally used as: - VOLTAGE REGULATORS5) The basic semiconductor amplifying device is a: - TRANSISTOR

Q4-541) What type of diode would be used to stop voltage spikes across a coil of a

relay – Double acting or Quenching diode2) A silicon diode in forward bias at 25 dgr C starts conducting at – 0.6 volts3) A germanium diode in forward bias at 25 dgr C starts conducting at   -

0.1 volts4) A zener diode is used for    - voltage stabilization5) A multi-layer PCB has  - ONE LAYER ON EITHER SIDE

Q4-641) An AC servo demand can be converted to drive a DC motor by the

introduction of a – DEMODULATOR2) Synchro indicator systems are used when the indication is required to

move – AT THE SAME RATE AS THE INPUT3) A linear variable differential transformer is used to measure position

feedback where  - AN OUTPUT WHOSE PHASE IS RELATED TO DIRECTION OF MOVEMENT AND AMPLITUDE LINEAR OVER A WIDE RANGE

4) A low frequency sinusoidal input will cause a closed loop servomechanism load to   - MOVE TO A DEMAND POSITION WITH NO OVERSHOOT

5) To reduce oscillations about a demand position  - THE AMOUNT OF VELOCITY FEEDBACK WOULD BE INCREASED

Q4-741) In a PNP transistor, which way does conventional current flow? – emitter

to collector2) In an integrated circuit, the components are inserted – By doping in

successive layers3) The typical voltage drop across an L.E.D is  - 2 volt4) A rate control servo system with a steady input voltage will give   -

constant speed5) Where are de-coupling capacitors used in digital circuits? – CLOSE TO

THE +VE PIN

Q4-84

Q4-51) A diode connected accross a relay coil is used to – DISSIPATE COIL

EMF ON SWITCH OFF2) An operational amplifier has – HIGH GAIN, HIGH INPUT

IMPEDANCE, LOW INPUT IMPEDANCE3) What are the bias  arrangements when a P-N-P transistor is used in the

common emitter configuration  - THE BASE IS NEGATIVE TO THE EMITTER

4) The connections to the F.E.T. are  - DRAIN, SOURCE, GATE5) The emitter follower has the following characteristics – VOLTAGE GAIN

LOW, INPUT IMPEDANCE HIGH, OUTPUT IMPEDANCE LOW

Q4-15 = Q4-14

Q4-251) What is the output of a half-wave rectifier? – A PULSATING DC

VOLTAGE2) What type of rectifier is constructed by sandwiching a section of

semiconductor material between two metal plates? – METALIC RECTIFIER

3) What type of bias makes a diode act as a closed switch? – FORWARD BIAS

4) What is used to show how diode parameters vary over a full operating range? – A CHARACTERISTIC CURVE

5) What is meant by diode ratings? – THEY ARE THE LIMITING VALUES OF OPERATING CONDITIONS OUTSIDE WHICH OPERATIONS COULD CAUSE DIODE DAMAGE

Q4-351) THE COLOUR OF AN LED IS DUE TO – the active materials2) A DIODE IS CONNECTED ACROSS AN LED TO – protect the LED if

AC is connected3) GERMANIUM DIODES ARE USED FOR   - rectification4) WHEN TESTING A DIODE WITH A MULTIMETER THE POSITIVE

LEAD IS CONNECTED TO    - anode, negative to cathode5) WHAT ELECTRONIC DEVICE CONNECTS ACROSS A RELAY TO

PREVENT BACK EMF   - schokky diode

Q4-451) The voltage drop across a germanium signal diode when conducting is

about: - 0.3 VOLT2) A bipolar transistor has three terminals named – EMITTER, BASE AND

COLLECTOR3) The three leads from a PNP transistor are named the: - COLLECTOR,

EMITTER AND BASE4) A low-level signal is applied to a transistor circuit input and a higher-level

signal is present at the output. This effect is known as:    - AMPLIFICATION

5) 5) The type of rectifier diode in almost exclusive use in power supplies is: - SILICON

Q4-551) A silicon diode, when compared to a germanium diode has – A HIGHER

FWD BIAS VOLTAGE2) When a servomotor overshoots after a step input and oscillates it is –

UNDER DAMPED3) The rotor of a desynn indicator is   - A PERMANENT MAGNET4) The position feedback from a potentiometer is    - ANTI PHASE5) A differential synchro has   - 3 PHASE STATOR, 3 PHASE ROTOR

Q4-651) A JFET is – VOLTAGE SENSITIVE2) What is required for the switching of a monostable multivibrator – 1

TRIGGER PULSE TO BOTH SWITCH ON AND OFF3) A capacitor resistor coupled multistage amp lets   - AC pass only4) A junction diode – has ONE P-N JUNCTION5) A germanium diode is used for   - RECTIFICATION

Q4-751) The resistance measured using an AVO between the Collector and

Emitter of a transistor is – SAME BOTH WAYS2) To check the output of a synchro stator it would be preferable to use – A

VALVE VOLTMETER3) Synchro capacitors are connected into synchro systems to   - INCREASE

THE ACCURACY OF THE CONTROL SYNCHRO4) In a slab desynn transmitter the   - PICK-OFFS ROTATE ON THE

SLAB RESISTOR5) A D.C. signal converted to a phase sensitive A.C. is – MODULATION

Q4-85

Module 4 Electronics - Amplifiers! 1) What are voltage amplifiers?

a) Circuits used to convert low current to a higher voltage

b) Circuits used to convert low voltage to a higher voltage

c) Circuits used to convert high voltage to a lower voltage

2) What are current amplifiers?

a) Circuits used to convert high current to lower current

b) Circuits used to convert low current to higher current

c) Circuits used to convert low voltage to higher current

3) To decrease the voltage gain of a common emitter amplifier you would increase the resistance in the

a) emitter circuit

b) collector circuit

c) base circuit

4) When a positive voltage is applied to the base of a normally biased n-p-n common emitter amplifier

a) the base current decreases

b) the emitter current decreases

c) the collector voltage goes less positive

5) The leads of an OP-Amplifier are?

a) Inverting lead, Non inverting lead, Output, + US, -US

b) Inverting lead, Non inverting lead, Output, Ground

c) Inverting lead, Non inverting lead, Output, +US, Ground

6) An amplifier current gain will be slightly less than 1, but its voltage gain will be high, if it is connected in the

a) common emitter configuration

b) common base configuration

c) common collector configuration

7) What happens if the inverting input of an OP is grounded and a signal applied to the non inverting input?

a) the output signal will be 90 degr out of phase in respect to the input signal

b) the output signal will be in phase in respect to the input signal

c) the output signal will be 180 degr out of phase in respect to the input signal

8) The common collector amplifier is also called the emitter follower circuit because

a) the emitter voltage follows the collector voltage

b) the emitter current follows the collector current

c) the emitter voltage follows the base voltage

9) What will happen if the non inverting input of a OP is grounded and a signal applied to the inverting input?

a) the output signal will be 180 degr out of phase in respect to the input signal

b) the output signal will be 90 degr out of phase in respect to the input signal

c) the output signal will be in phase in respect to the input signal

10) Amplifiers may be classified as

a) voltage amplifiers or impedance amplifiers

b) voltage amplifiers or power amplifiers

c) common emitter or common collector amplifiers

Question 1=bQuestion 2=bQuestion 3=bQuestion 4=cQuestion 5=aQuestion 6=bQuestion 7=bQuestion 8=cQuestion 9=a

Question 10=b

Q4-61) An element whose valence shell is only half filled is termed a/an –

SEMICONDUCTOR2) When an electron breaks away from its covalent bond the opening left is

called a – HOLE3) The conductivity of a semiconductor material is increased by a process

known as doping  - TRUE4) Pentavalent impurities have 5 valence electrons  - TRUE5) In a properly biased PNP transistor the most current flow will be from

the  - EMITTER TO THE COLLECTOR

Q4-16

1) The diagrams represent – MOSFET TRANSISTORS2) There are two basic Types of these transistors – ENHANCEMENT AND

DEPLETION MODE3) The two MOSFETs on the left are  - ENHANCEMENT TYPE4) The two MOSFETs on the right are – DEPLETION TYPE5) MOSFET stands for  - METAL OXIDE SEMICONDUCTOR FIELD

EFFECT TRANSISTOR

Q4-261) What does the letter "N" indicate in the semiconductor identification

system? – a SEMICONDUCTOR2) What type of diode has orange, blue, and gray bands? – 1N3683) To properly bias an NPN transistor, what polarity voltage is applied to

the collector, and what is its relationship to the base voltage? – A POSITIVE, MORE POSITIVE

4) Why is conduction through the forward-biased junction of an NPN transistor primarily in one direction, namely from the emitter to base? – BECAUSE THE N-MATERIAL ON ONE SIDE OF THE FWD BIASED JUNCTION IS MORE HEAVILY DOPED THAN THE P-MATERIAL

5) In the NPN transistor, what section is made very thin compared with the other two sections? – the P or base section

Q4-361) WHICH DIODE HAS A LOWER FORWARD BIAS VOLTAGE –

germanium2) A DIFFERENTIAL SYNCHRO HAS – one 3 phase rotor and one 3 phase

stator3) A DIFFERENTIAL SYNCHRO CAN BE USED AS A – transmitter or a

receiver4) POSITION FEEDBACK IN A SERVO SYSTEM IS   - 90 degree out of

phase5) VELOCITY FEEDBACK IS – proportional to servo motor speed

Q4-461) One important application for diodes is recovering information from

transmitted signals. This is referred to as: - DEMODULATION2) The following material is considered to be a semiconductor – SILICON3) A semiconductor is said to be doped when small quantities of the

following are added – IMPURITIES4) The connections to a semiconductor diode are known as: - ANODE AND

CATHODE5) Bipolar transistors usually have – 3 CONNECTING LEADS

Q4-561) When a servomotor has stopped, the rate feedback from a tachogenerator

Is – zero2) A tachogenerator is usually used for – RATE FEEDBACK3) A junction diode  - HAS 0NE P-N JUNCTION4) When the rotor of an AC tachogenerator is stationary, the rotor has    -

LOW CIRCULATING CURRENT DUE RESIDUAL VOLTAGE5) The output of a tachogenerator is  - SINUSOIDAL

Q4-661) Thermal runaway in a transistor is caused by – EXCESSIVE HEAT

CAUSING MAXIMUM CURRENT FLOW2) A single integrated circuit  Op Amp has how many pins? – 83) An atom with 5 electrons in its outer shell is part of  - an N type material4) In the Boolean algebra statement F = A.B.C , the gate described is     -

AND5) How is a push-pull transistor arrangement connected? – EMITTER TO

EMITTER

Q4-761) If velocity feedback in a servo system is above optimum, this will cause –

SLUGGISH OPERATION2) In an integrated circuit, the components are mounted by – METAL

OXIDE FILM ETCHED ONTO SURFACE3) The amount of rate feedback from a tach-generator is   -

PROPORTIONAL TO SPEED

4) In an electronic circuit with an operational amplifier connected in the push-pull configuration, the circuit    - UTILIZES BOTH SIDES OF THE INPUT SIGNAL

5) A control synchro system pointer is   - MOTOR DRIVEN

Q4-86

Module 4 Electronics: Synchros & Control Systems 1) The output of a tachogenerator used for rate feedback and is

a) proportional to position

b) proportional to speed of rotation

c) proportional to acceleration

2) AC power is supplied to

a) torque receiver only

b) both the torque receiver and torque transmitter

c) torque transmitter only

3) Which of the following methods of damping has a fast damp response and large velocity lag

a) Velocity feedback damping

b) Viscous damping

c) Error-rate damping

4) A differential synchro can

a) only be used as a transmitter

b) only be used as a receiver

c) be used as either a transmitter or a receiver

5) A Resolver has how many coils?

a) 2 coils on the rotor and 2 coils on the stator

b) 2 coils on the rotor and 3 coils on the stator

c) 3 coils on the rotor and 2 coils on the stator

6) Which of the following would help in removing the dead band?

a) Decreasing the gain of the error amplifier

b) Increasing the gain of the error amplifier

c) Increasing the internal friction of the motor

7) The -null- point on a control synchro is when the two rotors are

a) parallel to each other

b) at 90dgr to each other

c) at 180dgr to each other

8) The rotor of a desynn indicator is

a) a DC electromagnet

b) an AC electromagnet

c) a permanent magnet

9) When a servomotor has stopped, the rate feedback from a tachogenerator is

a) zero

b) maximum and in phase

c) maximum and anti-phase

10) The position feedback from a potentiometer is

a) in-phase

b) anti-phase

c) 90dgr offset Question 1=bQuestion 2=bQuestion 3=bQuestion 4=cQuestion 5=aQuestion 6=bQuestion 7=bQuestion 8=cQuestion 9=a

Question 10=b

Q4-71) The output of a resolver is measured in  - DEGREES2) 2) The most common method of nulling synchros is with a/an –

VOLTMETERS3) The property of a gyroscope that produces movement about the opposite

axis from which force is applied is known as – PRECESSION4) Gyros are held perpendicular about their rol and pitch axis by –

ERECTION TORQUES5) Vertical gyro synchros transmit ............... information – PITCH AND

ROLLS

Q4-17

1) The diagram represents a – PNP transistor2) Connections are – Collector, Base, Emitter3) On a PNP Transistor – base is connected to N-material4) On an PNP Transistor – Arrow points in5) On an NPN Transistor   - Arrow points out and is on Emitter

Q4-271) What percentage of current in an NPN transistor reaches the collector? –

98 percent2) What is the name given to the semiconductor device that has three or

more elements? – Transistor3) What electronic function made the transistor famous?  - Amplification4) In which direction does the arrow point on an NPN transistor? –

Outward5) What is one of the most important parts of any transistor manufacturing

process? – Quality control

Q4-371) A TORQUE SYNCHRO HAS AC. POWER TO THE V- ROTOR2) A ZENER DIODE IS USED FOR – Voltage Stabilisation3) WHEN A PCB IS FULLY ASSEMBLED IT IS COATED WITH  -

Conformal coating4) A DESYNN ROTOR IS – a Permanent magnet5) VELOCITY FEEDBACK WHEN THE SERVOMOTOR HAS

STOPPED IS  - Maximum anti-phase with the input

Q4-471) A semiconductor is described as a "general purpose audio NPN device".

This is a: - BIPOLLAR TRANSISTOR2) Two basic types of bipolar transistors are – NPN and PNP types3) A transistor can be destroyed in a circuit by – Excessive heat4) To bias a transistor to cut-off, the base must be – At the emitter potential5) Two basic types of field effect transistors are: - N-channel and P-channel

Q4-571) With a constant input to a speed control servo, the servo motor – MOVES

AT A CONSTANT SPEED2) A closed loop servomechanism – CAN HAVE EITHER POSITION OR

VELOCITY FEEDBACK3) Critical damping in a servomechanism is  - THE AMOUNT OF

DAMPING THAT RESULTS IN THE LOAD JUST NOT OSCILATING4) In a control synchro system the power supply is connected to the   -

TRANSMITTER ROTOR AND AMPLIFIER

5) Reverse rotation of a control transformer rotor can be caused by  - CONNECTIONS BEETWEEN THE TRANSFORMER ROTOR AND THE AMPLIFIER RESERVED

Q4-671) The cogging effect in synchros is rectified by – SKEWING THE ROTOR2) A transistor is said to be in the quiescent state when – NO SIGNAL IS

APPLIED TO THE INPUT3) In an unbiased p-n junction, current flow is  - ZERO, BECAUSE NO

CHARGES ARE CROSSING THE JUNCTION4) Torque synchro systems are normally used when the      - MECHANICAL

LOAD IS LOW5) In general the accuracy of a synchro system increases if the  - STATOR

CURRENT IS LOW

Q4-771) If, in a servo system, the amplitude from the feedback system is below

normal, the servo will – OSCILLATE2) A desynn instrument has a positive irregular increasing error, you would

adjust – LEVER ANGLE3) Torque synchro receiver bearing friction will cause  -

MISALLIGNMENT4) The purpose of the fly wheel incorporated in a synchro   - IS TO

PREVENT OSCILLATIONS5) When is maximum voltage induced into the rotor of a control synchro

transformer? – 0 DEGREES

Q4-87

Module 4 Electronics: Synchros & Control Systems 1) A differential synchro has

a) 3 phase stator, single phase rotor

b) 3 phase stator, 3 phase rotor

c) 2 phase stator, 2 phase rotor

2) In a torque synchro system, the power supply is connected to

a) the rotor windings of the transmitter only

b) the rotor windings of both the transmitter and receiver

c) the stator windings of the transmitter

3) To dampen and reduce overshoot errors in a synchro system

a) position feedback is used

b) velocity feedback is used

c) gain of the amplifier is increased

4) Complete power reversal to a torque synchro system will

a) displace the receiver rotor by 180dgr

b) cause reverse rotation of the receiver rotor

c) have no effect

5) In a velocity feedback damping system the net input to the amplifier is the voltage proportional to

a) speed of the output shaft minus the voltage proportional to the error signal

b) speed of the output shaft plus the voltage proportional to the error signal

c) error signal minus the voltage proportional to speed of the output shaft

6) The power supply to a torque synchro system is connected to

a) the transmitter rotor only

b) the transmitter and receiver rotors

c) the transmitter stator

7) If the rotor of the receiver in a torque synchro system was prevented from aligning with the transmitter rotor, then

a) the transmitter rotor will turn to align with the receiver rotor

b) a high current will flow in the stator windings

c) the receiver will overheat

8) Describe how the windings are connected when using a resolver synchro to convert from Cartesian to polar co-ordinates

a) The inputs are connected to the S1/S2 and S3/S4. R1/R2 are connected to the discriminator and servomotor. R3/R4 provides an output voltage

b) S1/S2 are connected to a discriminator and S3/S4 are short-circuited. The sin and COS inputs are connected to the rotor windings

c) The input is connected to winding R1/R2 and winding R3/R4 is short-circuited. The output is taken from stator windings S1/S2 and S3/S4

9) The result of cross connecting two of the transmission leads in a torque synchro system and then turning the rotor of the transmitter 60dgr clockwise would be

a) the receiver would move 60dgr counterclockwise

b) the receiver would move 60dgr clockwise

c) the receiver would move 120dgr counterclockwise

10) If the rotor of a control synchro sticks

a) the system hunts

b) high current will flow

c) the position feedback will oscillate Question 1=bQuestion 2=b

Question 3=bQuestion 4=cQuestion 5=aQuestion 6=bQuestion 7=bQuestion 8=cQuestion 9=a

Question 10=b

Q4-81) RPM indicators are motors that operate at the ........... of the frequency

output of the tach generator  - SYNCHRONOUS SPEED2) A system designed to produce at one location a position or indication

performed at another location is a/an – SERVO SYSTEM3) Which type syn4) chro system is most sensitive to null-voltage? – CONTROL5) Electrical zero is defined at the position in which the rotor coil is lined up

with axis of the – Y-winding6) Which type of synchro is used for heavy loads – control

Q4-181) The above PNP Transistor is – FWD BIASED2) On a Forward Biased PNP-Transistor electron path is referred to as –

EMITTER-BASE CIRCUIT3) Positive terminal of the battery repels the emitter holes – TOWARD THE

BASE4) The negative terminal drives the base electrons   - TOWARD THE

EMITTER5) When an emitter hole and a base electron meet  - THEY COMBINE

Q4-281) Which biasing method is the most unstable? – BASE CURRENT BIAS

OR FIXED BIAS2) What type of bias is used where only moderate changes in ambient

temperature are expected? – SELF BIAS3) When is degeneration tolerable in an amplifier? – WHEN IT IS

NECESSARY TO PREVENT AMPLITUDE DISTORTION4) What is the most widely used combination-bias system? – THE

VOLTAGE DIVIDER TYPE5) What two primary items determine the class of operation of an amplifier?

– THE AMOUNT OF BIAS AND THE AMPLITUDE OF THE INPUT SIGNAL

Q4-38

1) On an NPN Transistor the largest region is the – COLLECTOR2) On an NPN Transistor the smallest region is the – BASE3) On an NPN transistor most power is dissipated (heat developes and

requires a heat sink) at the  - COLLECTOR4) On an NPN transistor for normal transistor action most current flows

from   - COLLECTOR TO EMITTER5) A transistor in a circuit when used as switch in off position   - THERE IS

NO COLLECTOR CURRENT

Q4-481) Silicon in its pure form is – AN INSULATOR2) An element which falls somewhere between being an insulator and a

conductor is called – SEMICONDUCTOR3) In an n-type semiconductor, the current carriers are – ELECTRONS4) In a p-type semiconductor, the current carriers are – HOLES5) The following is a source of electrical energy – LEAD ACID BATT

Q4-581) PIN diodes are commonly used to – MAKE ATTENUATOR AND

SWITCH CIRCUITS2) Schottky diodes are commonly used to – CREATE HIGH FREQUENCY

MIXERS, DETECTORS, OR CLAMPS3) Varactor diodes are commonly used to   - PROVIDE THE RESONATOR

FOR VOLTAGE TUNED OSCILLATORS4) Velocity feedback – OPPOSE THE DEMAND INPUT5) Velocity lag can be decreased by  - DECREASING THE COLOUMB

FRICTION IN THE SYSTEM

Q4-681) When removing a microprocessor – CONSIDERABLE DAMAGE CAN

BE DONE BY STATIC DISCHARGE2) How do you increase voltage gain of an amplifier? – DECREASE INPUT

RESISTANCE3) In a control synchro the stator current ceases to flow when  - WHEN

POWER IS REMOVED4) In a speed control servo system (rate control), the purpose of the

tachogenerator is – TO MAKE IT RUN AT CONSTANT SPEED

5) When a hole diffuses from a p-region to the n-region it – RAISES THE POTENTIAL BARRIER

Q4-781) What is required for the switching of a monostable multivibrator – ONE

TRIGGER PULSE TO BOTH SWITCH ON AND OFF2) A capacitor resistor coupled multistage amp lets – AC and DC pass to the

next stage3) An oscillator operating at its natural frequency has feedback which is   -

In Phase4) Which mathematical operation is performed by a modulator amplifier? –

Multiplication5) What is meant by a bistable circuit? – The circuit has 2 stable states and

will stay in which one it is put

Q4-88

Q4-91) In a uni junction transistor, if the emitter junction is reverse biased , it

acts as? – A Simple Potential Divider2) A triac can be used? – Only on AC Circuits3) A silicon controlled rectifier (SCR) is a type of? – Thyristor4) An FET operating in the enhancement mode, will if connected to the

supply be? – Not Normally Conducting5) Current flow in an FET is controlled by? – Gate Voltage

Q4-19

1) The above PNP Transistor is – REVERSED BIASED2) PNP reverse-biased junction means – Negative voltage on the collector

and the positive voltage on the base3) Negative voltage on the collector and the positive voltage on the base   -

Block the majority current carriers from crossing the junction4) Minority current flow in the reverse-biased junction   - is very small

because of the limited number of minority current carriers5) Electrons leave the   - Negative terminal of the batt

Q4-29

1) What is the name of the term used to describe the condition in a transistor when the emitter-base junction has zero bias or is reverse biased and there is no collector current? – CUT OFF

2) How is the collector lead identified on an oval-shaped transistor? – BY THE WIDE SPACE BETWEEN THE COLLECTOR LEAD AND THE OTHER TWO LEADS ( EMITTER AND BASE)

3) What safety precaution must be taken before replacing a transistor?   - THE POWER MUST BE REMOVED FROM TH CIRCUIT

4) When you are using an ohmmeter to test a transistor for leakage, what is indicated by a low, but not shorted, reverse resistance reading? – A LEAKING TRANSISTOR

5) What are two transistor tests that can be done with an ohmmeter? – GAIN AND JUCNTION RESISTANCE

Q4-39

1) In the active region: some collector current, more than a

few tenths of a volt above the emitter, the transistor is used as – AMPLIFIER

2) In saturation, or _____________ . Collector near emitter in voltage, is acting like a forward biased diode. – TURNED ON

3) On an NPN transistor the base-collector diode is   - REVERSED BIASED4) On an NPN transistor the base-emitter diode is    - FWD BIASED5) The _________ region is very thin, like 10 wavelengths of light, to

facilitate passage through it – BASE

Q4-49

1) In the figure shown, 3 represents the – COLLECTOR OF PNP TRANSISTOR

2) In the figure shown, 2 represents the – BASE OF A PNP TRANSISTOR3) In the figure shown, 1 represents the  - EMITTER OF PNP

TRANSISTOR

4) The voltage drop across a silicon signal diode when conducting is about   - 0.6 VOLT

5) A single band of a diode represents the  - CATHODE

Q4-591) The junction barrier offers opposition to only – MAJORITY CARRIERS

IN BOTH REGIONS2) PIN diodes do not rectify at – MICROWAVE FREQUENCIES3) A diode formed by the deposition of a metal layer on a semiconductor,

creating a barrier junction is a – SCHOTTKY DIODE4) An increase in velocity feedback will – DECREASE THE SPEED THE

LOAD MOVES5) A two phase motor will stop when   - THE CONTROL PHASE IS ZERO

Q4-691) Amplifiers may be classified as – VOLTAGE AMPLIFIERS OR POWER

AMPLIFIERS2) What is a shottky diode used for? – VERY HIGH FREQUENCY

APPLICATIONS3) The control windings of a two phase servomotor is supplied with AC

voltage of – variable amplitude, variable phase4) In a torque synchro that includes a differential synchro the power supply

is connected to   - The transmitter and receiver rotors only5) If the rotor of a control synchro stick – HIGH CURRENT WILL FLOW

Q4-791) A zener diode is designed to operate – ABOVE ITS BREAKDOWN

VOLTAGE2) A JFET is – Voltage Sensitive3) A triac is a type of  - Thyristor4) If a junction diode is reverse biased too far, the output current   - Increase5) When a PN junction is forward biased, it conducts via  - Majority Carrier

Q4-89Internet

Q4-101) In FET's the regions are designated  - SOURCE, DRAIN AND GATE2) The initials FET stand for  - FIELD EFFECT TRANSISTOR3) In order to achieve emitter-collector current, the base-emitter junction

must be  - FWD Biased4) The regions of a transistor are called  - Base, Collector and Emitter5) A transistor is a semiconductor that can be used for  - Amplification

Q4-20

1) The interaction between the forward- and reverse-biased junctions in a PNP transistor is very similar to that in an NPN transistor, except that in the PNP transistor – MAJORITY CURRENT CARRIERS

2) Positive voltage on the emitter repels the holes – TOWARD THE BASE3) 90 percent of the holes that enter the base become attracted to the large

negative collector voltage and  - PASS RIGHT THROUGH THE BASE4) For each hole that is neutralized in the collector by an electron   -

ANOTHER ELECTRON LEAVES THE EMITTER AND STARTS ITS WAY BACK TO THE POSITIVE TERMINALS

5) Base region is made very thin to prevent the recombination of holes with - ELECTRONS

Q4-301) When you are testing the gain of an audio-frequency transistor with an

ohmmeter, what is indicated by a 10-to-1 resistance ratio? – NORMAL GAIN

2) The SCR is primarily used for what function? – THE SCR IS PRIMARILY USED FOR SWITCHING POWER ON OR OFF

3) When an SCR is forward biased, what is needed to cause it to conduct? – A GATE SIGNAL

4) What is the only way to cause an SCR to stop conducting?   - THE FWD BIAS MUST BE REDUCED BELOW THE MINIMUM CONDUCTION LEVEL

5) When used for ac current control, during which alternation of the ac cycle does the TRIAC control current flow? – DURING BOTH ALTERNATIONS

Q4-40

1) The left diagram represents – a High Pass Fiter2) The left diagram represents – Low Pass Filter3) _____________ can pass a low pass filter. – Lower Frequencies

4) _____________ can pass a high pass filter. – Higher Frequencies5) For a middle-frequency speaker a ____________ filter is used! – Band

Pass

Q4-50

1) The left symbol represents a – MOSFET2) The right symbol represents a – FET3) In the right figure shown, 2 represents the   - Gate of an N-channel

junction FET4) In the right figure shown, 3 represents the – Drain of an N-channel

junction FET5) In the left figure shown, 2 represents the  - Gate of a MOSFET

Q4-601) A tachogenerator output is – Variable Voltage, Constant Frequency2) Rate feedback can be obtained from a – Tachogenerator3) Positional feedback can be obtained from a – Potentiometer4) A diode that operates as a negative resistance device, used to make solid

state microwave or millimeter wave (>20 GHz) oscillators – Gunn and IMPATT Diode

5) A simple diode used for low frequency or DC applications – PN junction Diode

Q4-701) An open loop system is one which has – No Direct Feddback Loop2) Mechanical friction in a servo results in – Increased Damping3) A servo system that overshoots and oscillates is   - Under Damped4) The common collector amplifier is sometimes called the emitter follower

circuit because    - The Emitter voltage follows the base voltage5) In a toroidal resistance transmitter indicator system, the power supply is

connected to – The Brushes

Q4-801) Thermal runaway in a transistor refers to – High Current Flow when

Temperature Increases2) An astable multivibrator is a – Free Running Vibrator3) Resistors and capacitors are used to couple stages of amplifiers so that  -

Only A.C can be applied4) Op amps use what power supply? – (5v -15v DC)5) An RC connected amp has   - No DC across

Q4-90INTERNET

FINAL EXAM 1

Module 4 Final exam! 20 questions 1) Depletion layer is formed when

a) pieces of N-type and P-type material are subjected to voltages above 0.7V

b) a PN junction is forward biased more than 0.6V

c) a piece of N-type and a piece of P-type semiconductor are joined together

2) Pure silicon has a valency of

a) 4

b) 5

c) 3

3) Intrinsic silicon has

a) a very high resistance

b) a good conductivity

c) a very small amount of doping

4) If a PN junction is reverse biased it will

a) conduct only when a voltage applied accross is greater than 0.7V

b) not conduct any current at all

c) only conduct a small leakage current

5) Silicon diodes have an upper usable temperature range of

a) 150-200°C

b) 170-220°C

c) 200-350°C

6) Minority charge carriers in a piece of P-type germanium

a) do not exist above 0°C

b) are holes and are the result of conduction

c) increase as temperature increases

7) The conductivity of an intrinsic semiconductor can be improved by

a) heat treating the material

b) a process known as doping

c) the removal of any impurities

8) The reverse current of silicon and germanium diodes

a) rises exponetially for every 1°C rise in temperature

b) doubles for every 10°C rise in temperature

c) halves for every 10°C rise in temperature

9) When using diodes connected in series, the following arrangements is often used

a) a low value resistor is connected in series with each diode

b) a high value resistor is connected in series with each diode

c) a high value resistor is connected in parallel with each diode

10) A diode is said to be forward biased when the

a) anode is negative with respect to the cathode

b) anode is positive with respect to the cathode

c) cathode is more positive than anode

11) LED'S require a forward working voltage in the range of

a) 0.6V to 0.7V

b) 1.2V to 2V

c) 1.7V to 3.6V

12) LED's emit light

a) at a single wavelength

b) at a range wavelength

c) at a single frequency and polarisation

13) The approximate maximum reverse voltage for any LED is

a) 5V

b) 3.6V

c) 15V

14) The input terminals of an operational amplifier are called

a) positive input and feedback input

b) the positive and negative inputs

c) the inverting and non-inverting inputs

15) An operational amplifier with ideal characteristics would have

a) wide bandwidth, zero power dissipation and infinite open loop gain

b) very high input impedance, low output impedance and a high offset value

c) very high output impedance, low input impedance and a high offset value

16) A non-inverting operational amplifier

a) will provide an output 180° out of phase with its input

b) requires a minimum of two resistors to function correctly

c) with 100% feedback is known as a voltage folower

17) When forward biased a zener diode

a) acts as a voltage regulator

b) will conduct like an ordinary rectifier diode

c) will conduct until the zener voltage is exceede

18) SCR's must

a) be used in pairs when used in AC systems

b) only be used in AC systems

c) only be used in DC systems

19) The test digit for a 7 segment display is the number

a) 0

b) 7

c) 8

20) The three terminals on a FET are known as

a) base, collector, emitter

b) source, drain, gate

c) anode, cathode, gate

Question 1=cQuestion 2=aQuestion 3=aQuestion 4=cQuestion 5=aQuestion 6=cQuestion 7=bQuestion 8=bQuestion 9=c

Question 10=bQuestion 11=cQuestion 12=aQuestion 13=aQuestion 14=cQuestion 15=aQuestion 16=cQuestion 17=bQuestion 18=aQuestion 19=cQuestion 20=b

FINAL EXAM 2

Module 4 Final exam! 20 questions 1) In a trivalent material is added to intrinsic semiconductor, this would form a

a) covalent compound semiconductor

b) N-type semiconductor

c) P-type semiconductor

2) Adjacent silicon and germanium atoms form bonds, these bonds are known as

a) covalent bonds

b) ionic bonds

c) h2-bonds

3) The majority carriers within a piece of N-type silicon are

a) electrons

b) holes

c) ions

4) For a rectifier diode to function correctly it must have _____________ when tested with a multimeter

a) approximately equal milivolts drop on diode test position

b) low forward to reverse voltage drop

c) high reverse to forward resistance

5) The cathode on a LED is identified by

a) the shot lead and a flat on the casing

b) a band on the casing and a deformed lead

c) the short lead and a flat on the casing

6) A bipolar transistor is

a) can either be voltage or current operated

b) a voltage operated device

c) a current operated device

7) The three terminals of a bipolar transistors are labeled

a) source, drain and gate

b) collector, base and emitter

c) collector gate and emitter

8) Transistors can provide the following advantages

a) no arcing, good isolation between two circuits

b) provide either voltage or current gain

c) can withstand high reverse voltages and have low power consumption

9) For a PNP transistor to operateas a switch

a) negative feedback must be applied between base and collector

b) it must have a low value resistor in its emitter circuit

c) its base voltage must be negative with respect to its emitter

10) The function of a varistor is

a) to regulate an AC power supply

b) to suppresss noise spikes on a power supply

c) absorb noise glitches in a pure DC power supply

11) FET's are

a) current operated devices

b) voltage or current operated devices

c) voltage operated devices

12) A field effect transistor FET operating in depletion mode

a) is a "normally on" device

b) has a very high current gain

c) acts like a bipolar transistor

13) The three connections of a UJT - unijunction transistor - are

a) emitter, base one and base two

b) source, drain and gate

c) gate, base and substrate

14) The difinition of a "linear integrated circuit" is an IC that

a) has a linear response to input signals

b) processes digital and pulse signals

c) processes analogue signals

15) Current gain of a transistor can be defined by

a) output current divided by input current

b) input current multiplied by output current

c) emitter current multiplied by base current

16) Photo conductive diodes

a) have fast response times and must be operated in the reverse bias mode, when exposed to light the majority carriers increase

b) operate in forward bias mode and have a very fast response time when fed into a high impednce load

c) are operated in reverse bias mode and the current flow due to minority carriers increases when exposed to light

17) A SCR contains

a) 3 slices of simiconductor and and 3 junctons

b) 4 slices of simiconductor and and 3 junctons

c) 3 slices of simiconductor and and 4 junctons

18) If a 5V zener diode has a maximum power rating of 500 mW, what is the maximum current it can conduct?

a) 100mA

b) 20mA

c) 250mA

19) If an operational amplifier is configured so that it has multiple inputs, either of which will not interfere with another input, it is called

a) a multiplying amplifier

b) an operational amplifier

c) a summing amplifier

20) The principle materialo used to form the conducting tracks on a printed circuit board PCB is

a) tin

b) copper

c) brass

Question 1=cQuestion 2=aQuestion 3=aQuestion 4=cQuestion 5=aQuestion 6=cQuestion 7=bQuestion 8=bQuestion 9=c

Question 10=bQuestion 11=cQuestion 12=aQuestion 13=aQuestion 14=cQuestion 15=a

Question 16=cQuestion 17=bQuestion 18=aQuestion 19=cQuestion 20=b

FINAL EXAM 3

Module 4 Final exam! 20 questions 1) A device which has a high input impedance, low output impedance and high voltage gain is a or an

a) Class A amp

b) Class B amp

c) Op-Amp

2) Pin 3 on an op-amp has a + symbol. This designates

a) non-inverting input

b) positive input DC pin

c) positive offset null

3) The semiconductor substrate used in 'chips' is most commonly

a) silicon

b) germanium

c) arsenic

4)   What control system is used on an input that gives a controlled predetermined output?

a) Control servo

b) Open loop

c) Closed loop

5) Increasing velocity feedback from optimum will give

a) sluggish performance

b) faster performance

c) no change on the output

6) The output from a control transformer is

a) torque

b) DC voltage

c) AC voltage

7) The stator output voltages from a synchro resolver are

a) DC

b) AC single phase

c) 3 phase

8) The purpose of synchro capacitors in a differential synchro transmission system

a) reduce rotor current

b) to reduce stator current

c) reduce stator circuit impedance

9) To increase capacitance of a varactor diode

a) reverse bias voltage is increased

b) forward bias voltage is decreased

c) reverse bias voltage is decreased

10) Which diode has a lower forward bias voltage?

a) silicon

b) germanium

c) both are the same

11) What is the base material of a PCB?

a) semiconductor

b) conductor

c) insulator

12)   In which direction does the current flow on a PNP  transistor when forward biased?

a) Emitter to collector

b) Emitter to base

c) Collector to emitter

13) What does a resolver do?

a) Resolves a position into sine and cosine components

b) Adds two signals

c) Resolves a movement into sine and cosine components

14) If a diode has gone open circuit in a full wave bridge rectifier, the output frequency ripple is

a) twice the input frequency

b) the same input frequency

c) half the input frequency

15) In a tach-generator the output voltage is

a) directly proportional to the speed

b) inversely proportional to the speed

c) zero

16) An LED which emits red light uses

a) gallium arsenide

b) gallium phosphide

c) gallium arsenide phosphide

17) A linear variometer is

a) a special auto transformer for synchro system power supplies

b) a special synchro giving ac output proportional to shaft angle

c) an alternative term for a desynn system

18) In a synchrotel the rotating winding is

a) neither

b) rotor

c) stator

19) When forward biased the

a) positive lead is connected to both N and P type

b) positive lead is connected to the N type and negative to the P type

c) positive lead is connected to the P type and negative to the N type

20) An advantage of a FET when compared to a bi-polar transistor is

a) the switching time is quicker

b) the input resistance is higher

c) the input resistance is lowerQuestion 1=cQuestion 2=aQuestion 3=aQuestion 4=cQuestion 5=aQuestion 6=cQuestion 7=bQuestion 8=bQuestion 9=c

Question 10=bQuestion 11=cQuestion 12=aQuestion 13=aQuestion 14=c

Question 15=aQuestion 16=cQuestion 17=bQuestion 18=aQuestion 19=cQuestion 20=b

FINAL EXAM 4

Module 4 Final exam! 20 questions 1) A Zener diode is used across the output for a power supply circuit to

a) prevent thermal runway

b) give a full wave rectification

c) provide a steady DC voltage output without falling

2) In a printed board circuit, the surface resistance testing is

a) insulation resistance between adjacent printed conductor

b) the resistance between the two inductors

c) between the board and the conductor

3) To decrease the capacitance of a varactor

a) reverse bias should be increased

b) reverse bias should be decreased

c) forward bias should be increased

4)   The negative feedback for integrator is connected across a

a) resistor

b) inductor

c) capacitor

5) The voltage drop of silicon diode is

a) 0.7V

b) 1.0V

c) 1.3V

6) In an electronic circuit, if the anode of a diode is clamped to ground what is this called?

a) A negative limiting circuit

b) A low level clamping circuit

c) A high level clamp

7) If the feedback is ideal damped, the signal will

a) oscillate

b) overshoots once and return back

c) not overshoot

8) An LED which emits green light uses

a) gallium arsenide phosphide

b) gallium phosphide

c) gallium arsenide

9) The output of a control transformer is made

a) phase sensitive by transmitter rotor excitation and amplitude sensitive by direction of transmitter rotor movement

b) phase and amplitude sensitive by magnitude and direction of the transmitter rotor movement respectively

c) phase and amplitude sensitive by direction and magnitude of the transmitter rotor movement respectively

10) A transistor is used in

a) current amplifier

b) both current and voltage amplifier

c) voltage amplifier

11) The receiver rotor in a torque synchro system oscillates over an arc of approx 75 degrees. The probable cause is

a) one stator line open circuit

b) two stator lines reversed

c) short circuit between two stator lines

12)   Synchro capacitors are fitted

a) to improve sensitivity and accuracy

b) to make additional damping features unnecessary

c) to provide critical damping

13) A photodiode is operated under

a) reverse bias conditions

b) forward bias conditions

c) reverse or forward bias conditions

14) The purpose of a flywheel in a synchro receiver indicator is to

a) increase driving torque

b) encourage spinning

c) prevent spinning or oscillation

15) Position feedback is used to

a) ensure control surface moves to the demanded position by the controls

b) to prevent control surface oscillations while the surface is being moved

c) indicate to the pilot the position of the load

16) An integrated circuit is manufactured by

a) etching copper tracks onto an insulating board

b) computer hardware, which use individual circuits on ribbon

c) doping impurities into layers of intrinsic material

17) For a NPN transistor to conduct the collector circuit has to be

a) more positive than the emitter

b) more positive than the base

c) less positive than the emitter

18) A monostable vibrator

a) is switched on by a trigger pulse then within a pre-set time will eventually return to its original state

b) uses a trigger pulse to turn on and the same pulse to turn off

c) uses one pulse to turn on and another to turn off

19) A de-coupling capacitor in a PCB is used to

a) minimise transient currents

b) pass d.c only

c) pass a.c only

20) A typical use for resolver synchros is

a) engine power instrumentation

b) in compass comparator units

c) fly by wire systemQuestion 1=cQuestion 2=aQuestion 3=aQuestion 4=cQuestion 5=aQuestion 6=cQuestion 7=bQuestion 8=bQuestion 9=c

Question 10=bQuestion 11=cQuestion 12=aQuestion 13=a

Question 14=cQuestion 15=aQuestion 16=cQuestion 17=bQuestion 18=aQuestion 19=cQuestion 20=b

FINAL EXAM 5

Module 4 Final exam! 20 questions 1) What component is used to turn AC to DC?

a) Thyristor

b) Transistor

c) Diode

2) What is an intrinsic material?

a) A pure material

b) One with added elements

c) One with removed elements

3) What does the colour of an LED depend upon?

a) material

b) voltage

c) current

4)   What does the output voltage of an op-amp depend upon?

a) The gain of the op-amp

b) The op amp bandwidth

c) The resistors in the circuit

5) A Zener diode is used for

a) voltage regulation

b) voltage stabilisation

c) rectification

6) A thyristor SCR is a

a) multidirectional device

b) bi-directional device

c) unidirectional device

7) A bi-directional TRIAC has two SCRs connected in

a) series parallel

b) inverse parallel

c) parallel series

8) A thyristor can be forward biased by

a) negative pulse

b) positive pulse

c) positive or negative pulse

9) 'N' type materials are doped with

a) acceptors and donors

b) acceptors

c) donors

10) A junction diode if reverse biased too far, the output will

a) increase

b) reverse

c) stop

11) An increase in negative feedback

a) will make the driven device continuously rotate

b) increases system sensitivity

c) decreases system sensitivity

12)   Two push-pull transistors have what commanded?

a) Emitters

b) Collectors

c) Bases

13) In a Common Emitter Amplifier RE is used for

a) stabilisation

b) biasing

c) load control

14) An increase in amplitude of a rate feedback signal will cause

a) sluggish servo operation

b) instable operation

c) reduced hunting

15) Position feedback is used to

a) ensure control surface moves to the demanded position by the controls

b) to prevent control surface oscillations while the surface is being moved

c) indicate to the pilot the position of the load

16) What are the majority carriers for a forward biased PN junction device?

a) Electrons

b) Holes

c) Electrons and holes

17) Germanium in its pure state is

a) positively charged

b) neutral

c) negatively charged

18)   If the reverse bias voltage across a diode is too high

a) load current increases rapidly

b) load current reverses

c) load current reduces to zero

19) The rotor coil of a synchrotel

a) rotates only when a current flows in it

b) rotates

c) is stationary

20) Common Collector has the following characteristics

a) Low Voltage Gain, High Current Gain, Inverted Output

b) Medium Voltage Gain, High Current Gain, Non-Inverted Output

c) Medium Voltage Gain, Low Current Gain, Inverted Output

Question 1=cQuestion 2=aQuestion 3=aQuestion 4=cQuestion 5=aQuestion 6=cQuestion 7=bQuestion 8=bQuestion 9=c

Question 10=bQuestion 11=cQuestion 12=aQuestion 13=aQuestion 14=c

Question 15=aQuestion 16=cQuestion 17=bQuestion 18=aQuestion 19=cQuestion 20=b