### questions

Title
###### The major drawback of frequency multipliers is that they have:

The major drawback of frequency multipliers is that they have:

1. higher attenuation
2. complex construction methods
3. complex design
4. none of the mentioned
###### Oscillators operating at millimeter wavelength are difficult to realize and are also less efficient

Oscillators operating at millimeter wavelength are difficult to realize and are also less efficient.

1. true
2. false
###### A major disadvantage of frequency multipliers is that they multiply the noise factor along with frequency

A major disadvantage of frequency multipliers is that they multiply the noise factor along with frequency.

1. true
2. false
###### If a frequency multiplier has a multiplication factor of 10, then the increase in noise level due to frequency multiplication is:

If a frequency multiplier has a multiplication factor of 10, then the increase in noise level due to frequency multiplication is:

1. 10 db
2. 20 db
3. 25 db
4. 15 db
###### In a diode frequency multiplier, an input signal of frequency fo applied to the diode is terminated with at all frequencies other than required harmonic

In a diode frequency multiplier, an input signal of frequency fo applied to the diode is terminated with                   at all frequencies other than required harmonic.

1. real impedances
2. reactive impedance
3. complex impedance
4. none of the mentioned
###### Resistive multipliers are more efficient as compared to reactive multipliers

Resistive multipliers are more efficient as compared to reactive multipliers.

1. true
2. false
###### Reactive multipliers have a disadvantage that they cannot be used at very high frequencies and they become less efficient

Reactive multipliers have a disadvantage that they cannot be used at very high frequencies and they become less efficient.

1. true
2. false
###### For a resistive frequency multiplier of multiplication factor 2, the maximum theoretical conversion efficiency is:

For a resistive frequency multiplier of multiplication factor 2, the maximum theoretical conversion efficiency is:

1. 50 %
2. 25 %
3. 75 %
4. 12.5 %
###### is a device that converts electrons to photons or vice-versa

is a device that converts electrons to photons or vice-versa.

1. antenna
2. electron gun
3. photon amplifier
4. microwave tube
###### The basic equation of radiation that is applied to any antenna irrespective of the type of the antenna is:

The basic equation of radiation that is applied to any antenna irrespective of the type of the antenna is:

1. il= qv
2. iq = lv
3. i/l=q/v
4. none of the mentioned
###### When the separation between two lines that carry the TEM wave approaches λ the wave tends to be radiated

When the separation between two lines that carry the TEM wave approaches λ the wave tends to be radiated.

1. true
2. false
###### The number of patterns radiation pattern required to specify the characteristic are :

The number of patterns radiation pattern required to specify the characteristic are :

1. three
2. four
3. two
4. five
###### The beam width of the antenna pattern measured at half power points is called:

The beam width of the antenna pattern measured at half power points is called:

1. half power beam width
2. full null beam width
3. beam width
4. none of the mentioned
###### An antenna has a field pattern of E (θ) = cos2 θ, θ varies between 0 and 900. Half power beam width of the antenna is:

An antenna has a field pattern of E (θ) = cos2 θ, θ varies between 0 and 900. Half power beam width of the antenna is:

1. 330
2. 660
3. 12000
4. none of the mentioned
###### An antenna has a field pattern E (θ) =cos θ. cos 2θ. The first null beam width of the antenna is:

An antenna has a field pattern E (θ) =cos θ. cos 2θ. The first null beam width of the antenna is:

1. 450
2. 900
3. 1800
4. 1200
###### The solid area through which all the power radiated by the antenna is:

The solid area through which all the power radiated by the antenna is:

1. beam area
2. effective area
3. aperture area
4. beam efficiency
###### Power radiated from an antenna per unit solid angle is called radiation intensity

Power radiated from an antenna per unit solid angle is called radiation intensity.

1. true
2. false
###### A is a device that converts a guided electromagnetic wave on a transmission line into a plane wave propagating in free space

A                      is a device that converts a guided electromagnetic wave on a transmission line into a plane wave propagating in free space.

1. transmitting antenna
2. receiving antenna
4. mixer
###### Antennas are bidirectional devices

Antennas are bidirectional devices.

1. true
2. false
###### Dipole antennas are an example for:

Dipole antennas are an example for:

1. wire antennas
2. aperture antennas
3. array antennas
4. none of the mentioned

MCQs

Views