# In the program below, number of times the FIRST and SECOND JNZ instructions cause the control to be transferred to LOOP are respectively MVI H, 02H MVI L, 05H LOOP : DCR L FIRST : JNZ LOOP DLR H SECOND : JNZ LOOP

1.  5 and 2

2.  4 and 1

3.  259 and 1

4.   260 and 1

4

259 and 1

Explanation :
No Explanation available for this question

# For a sinusoidal input voltage, If the input voltage is connected to load for n cycles and is disconnected for m cycles, then rms output voltage is given by Where duty cycle K is given by

1.  m + n

2.  m – n

3.  mn

4.

4

Explanation :
No Explanation available for this question

# VI characteristic of emitter of a UJT is

1.  similar to CE with linear and saturation region.

2.  similar to FET with a linear and pinch off region.

3.  similar to tunnel diods in some respects.

4.  linear between the peak point and valley point.

4

similar to tunnel diods in some respects.

Explanation :
No Explanation available for this question

# An UJT used for triggering an SCR has the supply voltage VBB = 25 V. The intrinsic stand off ration, η = 0.75. The UJT will conduct when the blas voltage Vz is

1.  25 V

2.  ≥ 18.75V

3.  33.3 V

4.  ≥ 19.24 V

4

≥ 19.24 V

Explanation :
No Explanation available for this question

# A UJT relaxation oscillator circuit is drawn as shown below : If the value of timing resistor RT = 470 RΩ and CT = 0.01 F and intrinsic stand off ratio is 0.7, then period and frequency of oscillation is

1.  4.7 ms, 213 Hz

2.  5.64 ms, 177 Hz

3.  3.29 ms, 304 Hz

4.   6.71 ms, 149 Hz

4

5.64 ms, 177 Hz

Explanation :
No Explanation available for this question

# The latching current of SCR is 18 mA. Its holding current will be

1.  6 mA

2.  18 mA

3.  54 mA

4.  12 mA

4

6 mA

Explanation :
No Explanation available for this question

# If a positive voltage is applied to the gate of a reverse biased SCR, then

1.  this injects more electrons into junction J1

2.  this increases reverse leakage current into anode

3.  hesting of junction is unaffected

4.  failure of junctions occurs due to thermal run away

4

hesting of junction is unaffected

Explanation :
No Explanation available for this question

# At a room temperature of 30oC, minimum voltage and current required to fire a SCR is

1.  3 V, 40 mA

2.  0.6 V, 40 mA

3.  no limit

4.  3 V, 100 mA

4

3 V, 40 mA

Explanation :
No Explanation available for this question

# When the SCR conducts, the forward voltage drop

1.  is 0.7 V

2.  is 1 to 1.5 V

3.  increases slightly with load current

4.  remains constant with load current

4

Explanation :
No Explanation available for this question

# In the circuit drawn

1.  L, C, R circuit is for tunning out junction capacitance

2.  L, C is intended for filtering out the ripple

3.  R, C is called a snubber

4.  L is intended to reduce di/dt at switch on.

4