Electronics and Communication Engineering - Communication Systems

46.
The antenna diameter of a radar system is doubled. The maximum range will
be doubled
become four times
be halved
decrease to one fourth
Answer: Option
Explanation:

Range is proportional to antenna diameter.


47.
Which of the following microphones works on the piezoelectric effect?
Carbon
Condenser
Moving coil
Crystal
Answer: Option
Explanation:

As per piezoelectric effect application of pressure across the faces of a crystal produces an emf across the faces.


48.
In PAL system weighting of R - Y and B - Y signals is done to
prevent over modulation on saturated colours
prevent under modulation of saturated colours
allow over modulation of saturated colours
allow under modulation on saturated colours
Answer: Option
Explanation:

Weighting reduces the chances of over-modulation of the transmitter carrier in the presence of highly saturated colours when picture has very light or very dark parts.


49.
In case of probability of the message is 1 to 16 then the information will be
16 bits
8 bits
4 bits
2 bits
Answer: Option
Explanation:

.


50.
The saving of power in DSB-SC modulated at 80% is
NIL
80%
75.76%
50%
Answer: Option
Explanation:

.