HAL Paper
Diploma Trainee (Electronics)
Exam. Held on 26 Apr 2009-04-29
General Knowledge:- 30 Question
Electronics: - 70 Questions
General Knowledge
Electronics Questions
1. When the temperature of the room increased then the energy of semiconductor…
2. Power diode is generally made from: - Silicon/Germanium/Both/None of these
3. Thermionic Emission of electron is due to………….
4. When the both junction of NPN diode is reverse biased, then the diode is in which mode: -
a) Active b) Cutoff c) Saturation d) inverted
5. Which transistor mode gives the inverted output: -
a) Common Emitter b) Common Base c) Common Collector d) None of these
6. Which coupling gives the higher gain in case of amplifier: -
a) Capacitor coupling b) Impedance coupling c) Transformer coupling
7. Which distortion is least objectionable in audio amplification: -
a) Phase b) Frequency c) Harmonic d) Intermediation
8. A narrowband amplifier has a band pass nearly…………of central frequency:-
a) 33.3% b) 10% c) 50%
9. Frequency of wein bridge oscillator
10. Phase shift oscillator consists: -
a) RL b) RC c) RLC
11. Crystal oscillator frequency is very stable due to:-
12. Multivibrater Produces: -
a) Sine wave b) Square wave c) Smooth wave d) sawtooth
13. Convert the 101101 Binary number into octal no: -
a) 65 b) 55 c) 51 d) 45
14. 10 in BCD: -
a) 10100 b) 1100 c) 010111 d) None of these
15. Which PNP device has a terminal for synchronizing purpose:-
a) SCS b) Triac c) Diac d) SUS
16. In 3-Phase full converter, the output during overlap is equal to……………..
17. Addition of indium in semiconductor crystal makes: -
a) PNP b) NPN
18. Free electron exists in which band: -
a) 1 b) 2 c) 3 d) Conduction band
19. Ripple factor of half wave rectifier: -
a) 1.21 b) 0.48 c) 0.5
20. Efficiency of half wave rectifier: -
21. Transistor that can be used in enhancement mode:-
a) NPN b) UJT c) JFET d) MOSFET
21. Following contributes to harmonic distortion in Amplifier: -
a) +Ve feedback b) –Ve feedback c) Defective active device
22. High cutoff frequency: -
a) CB b) CC c) CE
23. Which is used as data selector?
a) Encoder b) Decoder c) modulator d) Demodulator
24. Read write capable memory: -
a) RAM b) ROM c) Both d) None of these
25. When modulation frequency is doubled, modulation index also doubled in case of: -
a) FM b) PM c) AM d) PM & FM
26. Term ’Noise temperature’ is used for
27. Video detector used in TV receiver is a….
a) Diode detector b) Ratio detector c) Phase detector
28. Which isn’t directly operated from mains: -
a) Half wave rectifier b) Centre tap rectifier c) Bridge rectifier d) Voltage doubler
29. In 3-Phase half wave rectifier each diode conducts for duration of: -
a) 30 Degree b) 45 Degree c) 60 Degree d) 180 Degree
30. If number of phase in a multiphase rectifier increased then: -
a) Output increased b) Output decreased c) Output smooth d) No change
31. Which output requires minimum filtration: -
a) Half wave rectifier b) full wave c) SCR half wave rectifier d) Voltage doubler
33. Transistor is a following operated device: -
a) Low voltage & low current device
b) Low voltage & high current device
c) Low current & high voltage device
d) High current & high voltage device