# In the amplifier shown below the ratio of small signal voltage gain when the emitter resister Re is bypassed by capacitor Ce to when it is not bypassed. (Hint: use simplified approximate h – parameter model)

1.  1

2.  hfe

3.

4.

4

Explanation :
No Explanation available for this question

# The frequency due to pole fp of emitter follower is

1.  fp = 2.8 HMz

2.  fp = 180 MHz

3.   fp = 280 MHz

4.  fp = 280 KHz

4

fp = 280 MHz

Explanation :
No Explanation available for this question

# The average value of the output voltage and fraction of a cycle that V0>0 are

1.  25.4V, 45%

2.  25.4V, 50%

3.  6.3V 50%

4.  12.7V, 50%

4

12.7V, 50\%

Explanation :
No Explanation available for this question

# The given shows the application of 555 timer as an astable multivibrator. The charging time and discharging timeconstants are respectively.

1.  R1 C and R2 C

2.  R1 C and (R1+ R2) C

3.  (R1+ R2) C and R1 C

4.  None

4

(R1+ R2) C and R1 C

Explanation :
No Explanation available for this question

# Consider the statements for degenerative feedback 1. It desensitizens the gain 2. It reduces non-linear distortion 3. It increases the gain 4. Reduces the effect of noise 5. It controls input and output impedance 6. Decreases the bandwidth Which of the above statements is/are correct

1.  1, 2, 3, 6.

2.   1, 2, 4, 5

3.  2, 3, 4, 5, 6

4.  1, 2, 4, 6

4

1, 2, 4, 5

Explanation :
No Explanation available for this question

# The expression for the loop gain of the oscillator when it starts to oscillate is.

1.

2.

3.

4.

4

Explanation :
No Explanation available for this question

# A monostable multivibrator is implemented by using 555 timer IC. If the capacitor value is 10 nF then value of resister R required that yields output pulse of 100 μ sec.

1.  10 K

2.  14.5 K?

3.  9.1 K?

4.  None

4

9.1 K?

Explanation :
No Explanation available for this question

# Consider the following statements 1. Under certain condition, the negative feedback in an amplifier can become positive 2. Positive feedback always leads to instability. 3. Negative feedback always increases the input impedance of the amplifier. 4. Under certain condition positive feedback increases the gain of amplifier. Which of the above statement/s is/are correct.

1.   1, 2, 3

2.  1, 2, 4

3.   2, 3, 4

4.  1 & 4 only

4

1 & 4 only

Explanation :
No Explanation available for this question

# The frequency of oscillation (fosc) of the oscillator is

1.

2.

3.

4.

4

Explanation :
No Explanation available for this question

1.  6.06

2.   6.4

3.  6.22

4.  12.12

4