UNIT II 2-Marks Questions

UNIT – II      2-Marks     Questions

1.      Differentiate oscillator and amplifier. [Nov. 2013]
2.      Mention two essential conditions for a circuit to maintain oscillations.      [April 2010] [Nov. 2011] [May 2012]
3.      State the Barkhausen criterion for sustained oscillation. What will happen to the oscillations if the magnitude of the loop gain is greater than unity? [Nov. 2013]
4.      In a Hartley oscillator, if L1 = 0.2 mH, L2 = 0.3mH and C=0.003 µF, calculate the frequency of its oscillations.  [May 2012] [Nov 2012]
5.      Draw the feedback circuit of a Colpitts oscillator.  Obtain the value of the equivalent series capacitance required if it uses a L of 100 mH and is to oscillate at 40 KHz. [May 2013]
6.      A tuned collector oscillator in a radio receiver has a fixed inductance of 60 µH and has to be tunable over the frequency band of 400 KHz to 1200 KHz.  Find the range of variable capacitor to be used. [April 2011] [Nov. 2011]
7.      In a RC phase shift oscillator, if R1=R2=R3=200 KΩ and C1=C2=C3= 100 pF, find the frequency of the oscillator. [April 2010]
8.      In an RC phase shift oscillator, if the frequency of oscillation is 955 Hz and R1=R2=R3= 680 KΩ. Find the value of capacitors. [Nov. 2010]
9.      A Wienbridge oscillator is used for operations at 9 KHz.  If the value of the resistance R is 100 KΩ, what is the value of C required?  [April 2011]
10.  What is the necessary condition for a Wien bridge oscillator circuit to have sustained oscillations? [May 2013]
11.  What is the major disadvantage of a Twin-T oscillator?  [Nov 2012]

12.  A crystal has the following parameters h=0.05 H, C=0.05 pF and mounting capacitance is 2 pF. Calculate its series and parallel resonating frequencies. [Nov. 2010]

No comments:

Post a Comment

Note: only a member of this blog may post a comment.