NTC - Amateur Class B Examination. Below are elements 6

1 December 2006 - 4F3EW


See the PARA handbook "So You Want to be a Ham".

These are sample questions which may come up in the above exam. The correct answer (Ans.) is given under the question number and there could be errors.


1. A vacuum tube having a suppressor grid
Ans. Pentode

2. A carbon resistor with color bands yellow, green and red has a value equal to
Ans. 4500 ohms

3. Two capacitors valued at 400 and 600 uF consecutively are connected in series in an electric circuit.  What is the value of its equivalent capacitance?
Ans. 240 uF

4. The ratio of change in plate current and the grid voltage of a triode amplifier, keeping its plate resistance constant is the
Ans. transconductance of the vacuum tube

5. Three identical inductors valued at 90 millihenrys are connected in parallel.  The total equivalent inductance is equal to
Ans. 30 mH

6. A vacuum tube having a filament, anode, cathode, and control grid is
Ans. triode

7. The symbol used to designate amplification factor of a VT amplifier
Ans. MU

8. Commonly used diode as RF switch
Ans. PIN

9. The three terminals a silicon-controlled rectifier (SCR) are the anode, cathode and
Ans. gate

10. Type of diodes normally used in voltage regulator circuits
Ans. Zener

11. What is the forward resistance of an ideal diode
Ans. zero

12. What diode has a negative resistance?
Ans. Tunnel

13. A vacuum tube having a filament, a cathode and anode is
Ans. diode

14. A vacuum tube having a filament, a cathode, anode, and control grid
Ans. triode

15. Rayleigh fading occurs several times per minute during
Ans. troposcatter

16. Two inductors valued at 30 H and 60 respectively are connected in parallel.  What is the total equivalent inductance?
Ans. 20 H  (15 in reviewer)

17. Two capacitors valued at 40 uF and 60 uF are connected in series, the total equivalent capacitance?
Ans. 24 uF

18. The Beta of a transistor is its
Ans. current amplification factor

19. The sub-harmonic of 1000 kHz
Ans. 500 kHz

20. A conductive circuit pattern applied to one or both sides of an insulating substrate is known as
Ans. printed circuit

21. 3 db points are also known as 
Ans. half-power points

22. What is the capacitive reactance of a capacitor whose value is 350 pF, operating on frequency 1200 kHz?
Ans. 379 ohms

23. A series circuit consists of an inductance of 500 uH and a capacitance of 400 pF. What is the resonant frequency?
Ans. 356 kHz 

24. The majority carrier in P-type semiconductor materials
Ans. hole

25. What is the majority carrier in N-type semiconductor material?
Ans. electron

26. Diodes normally used to low frequency due to its high internal capacitance
Ans. junction

27. In semiconductor circuit, the ratio of collector current to base current is known 
Ans. Beta

28. The minority carrier in N-type semi-conductor material
Ans. holes

29. A common semi-conductor diode used as radio frequency switch
Ans. PIN

30. A type of semi-conductor diode having a negative resistance region
Ans. Tunnel

31. An electronic semi-conductor component capable of controlling electron flow through it is known as
Ans. solid-state device

32. A disadvantage of using semi-conductor as against vacuum tubes
Ans. low heat resistance

33. Doping germanium with gallium causes
Ans. hole current flow

34. Solid state lamps are also known as
Ans. LED

35. An emitter follower transistor amplifier circuit is also known as
Ans. common-collector

36.A varactor is
Ans. variable capacitor diode

36. What is a photojunction device?
Ans. Solid-state device that increases its conductance when struck by protons of light or heat

37. The three basic parts of transistors are the base, the collector and the
Ans. emitter

38. The two very useful semi-conductors are germanium and
Ans. silicon

39. Zener diodes are diodes
Ans. that operate on its avalanche voltage

40. The greatest advantage of a transistor over a vacuum tube is
Ans. Size

========================