Which one of the following is not a type of modulation?

Amplitude Modulation

Frequency modulation

Pulse modulation

Phase amplitude modulation

Correct Answer : Pulse modulation

Explanation : Modulation is of three types, frequency modulation, amplitude modulation and phase modulation. Pulse modulation is a type of amplitude modulation.

Recently Updated in Avionics Questions

The maximum peaks of an electromagnetic wave are separated by a distance of 8 in. What is the frequency?

256.4Khz

256.7Mhz

1477.8Khz

1477.8Mhz

Correct Answer : Option (D) : 1477.8Mhz

Explanation : Wavelength =8 in.= 0.203 m
Frequency = 300/0.203 = 1477.8Mhz.

SHF Em waves are used in?

Underwater communication

Satellite communication

Aircraft to ATC communication

Ground to ground communication

Correct Answer : Option (B) : Satellite communication

Explanation : SHFs or Super High Frequency EM waves are those which lie between the frequency range of 3 to 30GHz range. These microwaves frequencies are widely used in satellite communication and radar.

Which one of the following is not a source of infrared radiation?

Sun

Books

Light bulbs

Human bodies

Correct Answer : Option (B) : Books

Explanation : Infrared radiation is generally associated with heat. Infrared is produced by light bulbs, human bodies, and basically any physical equipment that generates heat.