Electronics and Communication Engineering - Communication Systems

11.
In the television system in India, each frame is scanned
100 times
50 times
20 times
10 times
Answer: Option
Explanation:

Each frame is divided into odd and even fields. Each field is scanned 25 times so that each frame is scanned 50 times.


12.
Each kilometer of travel in electromagnetic radiation means a time delay of
330 μs
33 μs
3.3 μs
0.33 μs
Answer: Option
Explanation:

Since velocity of em waves is 300 m/ms, each kilometer means time delay of 3.3 μs.


13.
A video monitor is exactly similar to TV receiver.
True
False
Answer: Option
Explanation:

Trinitron is a colour picture tube.


14.
A RADAR can be used to
aim a gun at an aircraft
to direct guided missiles
to search submarines
all of the above
Answer: Option
Explanation:

Radar is used for all the three purposes.


15.
In single tone AM modulation, the transmission efficiency for m = 1 is
33.3%
50%
100%
16.65%
Answer: Option
Explanation:

Since signal power = 0.5 PC and total power is 1.5 PC efficiency is 33.3%.