FESCO Past Paper (solved)

his is a previous paper of FESCO for SDO/ Junior Engineer / AM Operations

1. Which is not the basic part of T/F? A) Corey B)Primary Winding C) Secondary winding D) Mutual Flux 

2. Fourier series representation of continuous signal require ___________ no: of harmonically complex exponents: a) N b) n+N c) 1 d) Infinite 

3. In 8085............is a part of control unit? A) ROM. B) Instruction registers. C) Ram. D) Op-code

4. Oscillator whose frequency can be changed by variable DC control voltage? a) Triangular wave oscillator, b) Wien bridge oscillator, c) Crystal oscillator, d) Voltage controlled oscillator 

5. The circuit produces output waveform without an external signal source? a) Filter, b) Amplifier c) Oscillator, d) None

6. Difference between JFET and MOSFET? PN junction 

7. The part which gives the instruction of Microprocessor, what to do is? a) RAM, b) RAM, c) Op code, d) On code

8. The parameter hfe corresponds to? a)Bdc its beta(dc), b)Bac (beta ac), c) r'e, d) r’c

9. Diode limiters are used to? a) Limit +ve portion, b) Limit -ve portion, c) Constant dc output d) Level to 0.7 e) Both A and B

10. FIR filters can be designed to achieve? A) linear phase B) Inverting phase

11. In 8085, the content of the instruction register is split into---------------nibble? a) 4, b) 2

12. State during which nothing has happened indicated by which instruction.....NOP (?)

13. FIR filters do not have.....feedback 

14. Due to velocity saturation region a) at pinch off b) before pinch off c) after pinch-off, etc.

15. Z transform is centered at.........? Origin

16. Optical power depends on a) quantum b) dark current, etc. or d) all?

17. Which source provides constant voltage a) ideal current source b) ideal voltage source c) both ideal current and voltage source, d) both real voltage and current source

18. JFET advantages? Small size, low noise, high power gain, etc. All 

19. JFET drawback......? low gain width product 

20. If emitter junction is forward biased, collector junction reversed biased, the amplifier is in a) active mode b) saturation, etc.

21. Which transformed used to convert signals from time to frequency domain? a) Laplace b) Fourier, etc.

22. ROC converges if poles and zeros lie inside? 1) origin, 2) Z=1

23. RLC at low frequencies has more Z because of? a) Xc is large, b) Xl is large, c) Xc is small d) Xl is small

24. In RLC complex system, analyzed by resistance, inductance and? Current, Inductance, Voltage, capacitance 

25. Sum of voltage drop in a loop is Zero

26. In BJT Vce is important because it can be used to check whether? a) working in saturation, b)working in cut off, c)defective, d) All

27. The dc operating point of an amplifier specified by voltage and current value? a) gain, b) q point, c) load line, d) none