TRADESMAN - TV MAINTENANCE AND REPAIRS - TECHNICAL EDUCATION.pdf (Size: 1.36 MB / Downloads: 1)
1.Unit of specific resistance is :
(A)Metre-ohm,
(C ) Ohm-meter
(B) Centimeter-ohm-metre (D) Ohm-meter2

2. Find the resistance of a manganin wire with one third the length and one third the diameter of a silver wire of resistance lΩ. The specific resistance of manganin is 30 times that of silver:
(A)90Ω(B)10Ω
(C )9Ω(D)1Ω

8.When resistors of different values are connected in parallel--------across each resistoris the same.
(A)Current(B) Potential drop
(C )Power(D)Temperature

4. Which among the following is a linear component?
(A)Diode(B)Varistor
(C )Thermistor(D)Resistor

5.A short circuited path has practically
(A)infinite (C ) medium
— resistance. (B) unit (D) zero

6.When two 16 Ω resistors are connected in parallel to a 24V battery, find the current following in the circuit?
(A)4A(B)3A
(C )2A(D)1A1A

7. Which among the following is an active element?
(A)Resistors(B) Inductor
(C ) Capacitor(D) None of these

8. A SPDT switch has ON positions:
(A)One(B)Two
(C )Three(D)None of these

9.Fuses protect the electric circuit against excessive:
(A)Voltage(B)Temperature
(C )Current(D)(B) & (C )

10.One of the following is not associated with PCB development process : 
(A) Etching(B) Layout
(C ) Soldering(D) EDA tools

11.The impurity atoms added to make a N type semiconductor are called
(A)Donors(B)Acceptor
(C )Trivalent atom(D)None of these

12.Example for a pentavalent impurity atom is :
(A)Phosphorous(B)Carbon
(C )Aluminium(D)Galium

13. The barrier voltage for Ge (A) increases (C ) decreases
for a rise in temperature.
(B)remains the same (D) exponentially increases

14. A Schottky diode has (A) one (C ) three
junctions.
(B)two
(D) none of these

15. A reverse biased diode is equivalent to an ideal diode in series with a resistance in the range of :
(A)G(B) MG
(C )KG(D) none of these

16. Zener diodes with breakdown voltage more than 6V operate under :
(A) Forward breakdown(B) Reverse breakdown
(C )Zener breakdown(D) Avalanche breakdown

17. Which among the following operates in the reverse biased mode?
(A) Photodiode(B) light emitting diode
(C ) Schottky diode(D) none of these

18.The PIV of a diode in a half wave rectifier is:.
(A) 2Vm(B) Vm
(C ) Vm/2(D) 2Vm /л

19.Find the D.C output voltage of a half wave rectifier circuit that operates at 230V, 50Hz AC supply with a transformer of turns ratio 10:1:
(A) 23 V(B) 32.5 V
(C ) 10.35 V(D) none of these

20.The basic application of an inductive filter is in acircuit with:
(A) low load current(B) high load resistance
(C ) lower capacitance(D) heavy load currents

21.The % voltage regulation of a power supply which gives 95V under full load condition and 100V at no load condition is:
(A) 0.053(B) 0.53
(C ) 5.3(D) 53

22.SCR is:
(A) Silicon Content Rectifier(B) Silicon Controlled Rectifier
(C ) Silicon Conductive Rectifier(D) None of these

23.Which among the follwing is a bidirectional device with a gate controlWhich among the following is a bidirectional device with a gate control?
(A) UJT(B) SCR
(C ) DIAC(D) TRIAC

24.For proper amplification, a transistor must operate in theregion.
(A) Forward biased(B) Active
(C ) Reverse biased(D) Saturation

25.Thermocouple is a:
(A) amplifier(B) oscillator
(C ) transducer(D) none of these

26.A transistor amplifier connected in
(A)CE (C ) CC
configuration has the highest voltage gain.
(B)CB
(D)None of these *

27.The power dissipation capability of a transistor can be increased by using a :
(A)Resistor(B)Capacitor
(C )Heat Source(D)Heat sink

28.Which type of amplifier are used in the initial stages of PA system?
(A)RC coupled(B)Transformer coupled
(C )Impedance coupled(D)Direct coupled

29.When sine wave is given to an amplifier, the output exists for less than a half cycle. This is an example for-------------amplifier.
(A) class A (C ) class C
(B)class B
(D)class AB

30.In order to match a 16Ω loud speaker to an amplifier to get an effective load of lOΩ, the transformer must be with turns ratio :
(A)25
(C )16
(B) 20 (D)10

31.In a class B push pull amplifier the output signal gets distorted, with a time interval between the positive and negative half cycles. This is called------------ distortion.
(A) Amplitude
(C ) Frequency
(B)Crossover
(D)None of these

32. FET is a controlled device.
(A) Current (C ) Voltage and Current (B)VoltageVoltage
(D)None of these 

33.Type of feedback used in oscillator is 
(A) Positive (C ) Both (A) & (B)
(B)Negative 
(D)Indirect

34.In a Hartley oscillator, the tank circuit has a capacitance of 0.01puF and an inductance of 50mH. Determine the frequency of oscillation :
(A)0.7 Hz(B)7 Hz
(C )7 KHz(D)none of these

35.The oscillator generally used to generate signals in the audio frequency range is :
(A)Hartley(B)Col pitts
(C )RC phase shift(D)Crystal

36.A single stage CE amplifier introduces a phase shift of-----
(A) 45°(B) 90°
(C ) 135°(D) 180°
in the output signal.

37.A bistable multivibrator circuit changes from one state to the other:
(A)automatically(B)when the power turns ON & OFF
(C )when there ia atrigger pulse(D)doesn't change state.

38.A circuit that generates a square wave from a sine wave is :
(A)Integrator(B)Differentiator
(C )Clamper(D)Schmitt trigger

39.The criteria for a good differentiating circuit is that its time constant should be :
(A)Much smaller than that of the input signal
(B)Much larger than that of input signal
(C )Equal to that of the input signal
(D)None of these

40.A circuit in which a lamp is controlled by two switches in series is equivalent to a logic gate. Identify the gate:
(A)OR(B)AND
(C )XOR(D)NAND

41.The word TELE’ in TELEVISION means :
(A)to see(B)at distance
(C )to transmitto transmit(D)to receive

42.Dimension of a TV receiver is specified by —— of the screen.
(A) Length(B)WidthWidth
(C ) Diagonal length(D)None of these

43.Which among the following is not a complimentary colour :
(A) Yellow(B)Cyan■ Cyan
(C ) Magenta(D)BlueBlue

44.The dominant spectral colour of the received light is termed as :
(A) hue(B)luminance
(C ) saturation(D)none of the abovenone of the above

45.Grassmans law is:
(A) Y= 0.59R+0.30G+0.1 IB(B)Y=059B+0.30G+0.11R
(C ) Y= 0.59G+0.30R+0.1 IB(D)None of these

46.Audible frequency range is*:
(A) 20 kHz to 200 kHz(B)20Hz to 20kHz20 Hz to 20 kHz
(C ) 200 Hz to 200 kHz(D)none of these

47.Which of the following is not related to a tape recorder?
(A) pinch roller(B)lenslens
(C ) supply Bpool(D)leaf switch

48.Highest capacity in an optical disc can be obtained by using a laser beam of
(A) green(B)lR
(C ) red(D)blueblue

49.Microwave frequencies are used for satellite communication because :
(A) smaller antenna can be used(B)gives high directive gain
(C ) gives higher bandwidth(D)all of the above

50.The duration of H sync pulse is :
(A) 4.7pus(B)1.5pu 8
(C ) 5.8pus(D)12pus

51. TV channels used in India are in the ---------- hand.
(A) UHF(B)VHF
(C ) Microwave(D)None of theseNone of these

52.The intercarrier frequency used for TV transmission in India is :
(A) 4.5 MHz(B)4.5 KHz
(C ) 5.5 MHz(D)5.5 KHz

53.CCIR-B standard is popularly known assystem.
(A) 625 line European(B)525 line America525 line American
(C ) 625 line American(D)none of the thesenone of these

54.The TV programmes in America are brighter than in UK, because of:
(A) high mains frequency(B)higher mains voltagehigher mains voltage
(C ) lower mains current(D)none of thesenone of these

55.Vidicon camera tube is based on the principle of:
(A) Photoemission(B)Photoconduction
(C ) Phototropism(D)None of theseNone of these

56.Night Vision camera tubes are sensitive to :
(A) Visible light(B)UV radiation
(C ) Red light(D)IR radiation

57.deflection is used in TV tubes? 
(A) electrostatic, magnetic(B)magnetic, electrostatic
(C ) manual, magnetic(B)manual, electrostatic

58.PlL stands for:
(A) Primary Colours in Line(B)Phosphors in linePhosphors in line
•(C ) Precision in line(D)None of theseNone of these

59.When the raster gets stretched at the corners, it is called :
(A) Barrel effect(B)Pincushion effect
(C ) Ghost effect(D)None of theseNone of these

60.Picture tubes have high vacuum inside :
(A)To prevent influence of external magnetic fields
(B)To ensure collision free movement of electrons
(C )To reduce the weight
(D)All of the above.

61.Which among the following belong to the TV tuner stage?
(A)RF amplifier(B)Local oscillatorLocal oscillator
(C )MixerMixer(D)All of the above

62.oscillator’s frequency is:
(A)100 Hz(B)50 Hz
(C )15625 Hz15625 Hz(D)25 Hz

63.AFC circuit is included in the :
(A) Sound section(B) Tuner section
(C ) V-deflection section(D) H-deflection section

64.H- sync pulse is separated from a V-sync pulse using a :
(A) Trap circuit(B) Integrator •
(C ) Differentiator(D) Mixer

65.Which among the following is a merit of an IF stage :
(A)high gain(B)high selectivity
(C )high stability(D)all of the above

66.Which of the following is related with the production of electromagnetic waves by an antenna?
(A)Maxwell's equation(B)Lenz’s law
(C )Ohm’s law(D)None of these

67.EHT required for a 50 cm size colour picture tube is about :
(A) 5 KV(B) 10 KV
(C ) 25 KV(D) less than 5 KV

68.Identify the instrument for tenting and alignment of TV receivers :
(A)Pattern generator(B)Colour bar generator
(C )Wobulator(D).All of the above

69.The fault that occurs when the V-sweep oscillator frequency differs from that of V-sync pulse:
(A)Picture rolling(B)Diagonal splitting
(C )Keystoning(D)Foldover

70.In order to get global coverage there can be a minimum of ----------------satellites in the Geostationary orbit.
(A)4(B)3
(C )2(D)1

71.In HDTV system active scanning lines per frame is :
(A)1250(B)1175
(C )1125(D)1080

72.For the production of EHT for picture tube, the rectifier used on the secondary side of the transformer is:
(A)Bridge(B)Center tapped
(C )Halfwave(D)Silicon controlled

73.Which among the following ia not an advantage of SMPS?
(A) High efficiency(B) High heat dissipation
(C )Usage of high frequency Transformer (D)Better regulation

74.Identify a technician control in a TV receiver :
(A)V hold(B)Contrast control
(C )Channel selection(D)Brightness control

75. The picture tube in which three electron guns are mounted at 120° with respect to each other is:
(A)PIL(B)Vidicon
(C ) Delta gun' (D) None of the above

77.Radiowaves move in free space with a velocity :
(A)3 x 10® m/s
(C ) 0.3 x 10s m/s
(B) 3 x 10s km/s (D) none of the above

78.Flickering can be eliminated by adopting :
(A) Progressive scanning (C ) both (A) & (B)
(B) Inter laced scanning (D) None of the above

79.AM and FM radio receivers are very similar except for the presence of: 
(A) Mixer(B) Local oscillator
(C ) Limiter(D) AF amplifier

80.In TV' programmes, picture is modulated.
(A) amplitude, amplitude (C ) frequency, amplitude
modulated and sound is
. (B) frequency, frequency (D) amplitude, frequency

81.The highest peak in the Eastern Ghats is called
(A)Kanchenjunga(B)Anamudi
(C )Lakkidi(D)Ambalavayal Peak

82.Name of the plateau that lies between the Aravalli and the Vindhyan ranges
(A)Malwa plateau(B)Deccan plateau
•(C )Talaigao plateau(D)Chota Nagpur plateau

83.Who was the leader of the Kallumala Samaram? 
(A) Karuppan (C ) C.K. Janu
(B) Sahodaran Ayyappan (D) Ayyankali

84. Language of the journal Mahratta published by Tilak
(A) Marathi(B) Hindi
(C ) English(D) Urdu

85.“No caste, no religion, and no god" : who said it?
(A) Dr. Palpu (C ) Ayyankali
(B) Sree Narayana Guru (D) Sahodaran Ayyappan

86.Leader of Pattini Jadha from Malabar to Madras
(A) P. Krishna Pillai (C ) Mannath Padmanabhan
(B) A.K. Gopalan (D) K. Kelappan

87.Founder of Prathyaksha Raksha Sabha :
(A) Kumaran Gurukkal (C ) Janu Amma
(B) Poikayil Kumaragurudevan (D) Yohannan Asan

88.“One communalism does not end the other, each feeds on the other and both fatten" who said it?
(A) Gandhiji
(C ) Rabindranath Tagore
(B)Jawaharlal Nehru
(D)Jayaprakash Narayan

89.Which one of the following offered an alternative for the separate electorate (communal award) proposed by Prime Minister Ramsay MacDonald?
(A) Gandhi-Irwin Pact(B)The Act of 1935
(C ) Poona Pact(D)Karachi Session of the CongressKarachi Session of the Congress

90.Editor of the Vivekodayam journal:
(A) Ramakriahna Pillai(B)K.P. Kesava Menon
(C ) C. KrishnanCD)Kumaran Asan

91.Which city is going to host 2022 winter Olympics hence will become the first to host winter and summer Olympics?
(A) Paris(B)Qatar t
(C ) Beijing(D)Montreal 

92.Author of The Long Walk to Freedom :i
(A) Booker T. Washington(B)Nelson Mandela
(C ) Martin Luther King(D)Tabo Mbeki

93. Nobel Prize in Economics for 2014 was awarded to :
(A) Jean Tirole(B)Eugene F. Fama
(C ) Peter Hansen(D)R.J. Schiller

94.Post-dated cheque is a comment made by Mahatma Ghandhi on :
(A) Cripps Mission(B)Cabinet MissionCabinet Mission
(C ) Round Table Conference(D)Act of 1935Act of 1935

96.Who was the founder of Khudai Khidmatgars?
(A) Nawab Vikar-ul-Mulk(B)Bhagat Singh
(C ) Khan Abdul Gafar Khan(D)M.A Jinnah

96.Who started the journal Al-Islam?
(A) Shoukal Ali(B)Moulana Abul Kalam Azad
(C ) Abdur Rahim an(D)Vakkom Moulavi

97.‘Safety Valve' theory is associated with one of the following:
(A) Indian National Congress(B)Communist Party
(C ) BJP(D)Muslim League

98.Formation of Thriu-Cochin (Travancorre-Cochin) Statewas in:
(A) 1956(B)1949
(C ). 1947(D)19461946

99.Year of Vaikom Satyagrah :
(A) 1924(B)1926
(C ) 1930(D)19321932

100. NITI Ayog replaces one of the following :
(A)UGC
(B)Planning Commission
(C )Trade & Economic Relations Committee
(D)SEBI