Electronics and Communication Engineering - Communication Systems

26.
The rate at which information can be carried through a communication channel depends on
carrier frequency
bandwidth
transmission loss
transmitted power
Answer: Option
Explanation:

Rate of information depends on bandwidth.


27.
Some types of traps used in video IF amplifier of colour TV are
shunt traps
series traps
absorption traps
all of the above
Answer: Option
Explanation:

All these are used.


28.
Direct and reflected sound waves may interfere with each other.
True
False
Answer: Option
Explanation:

PAS use moving coil microphones.


29.
A carrier is simultaneously modulated by two sine waves having modulation indices of 0.4 and 0.3. The total modulation index will be
0.1
0.7
0.5
0.35
Answer: Option
Explanation:

m1 = 0.4, m2 = 0.3

.


30.
A 1000 kHz carrier is simultaneously modulated with 300 Hz, 800 Hz and 2 kHz audio sine waves. Which of the following frequency is least likely to be present in the output?
1002 kHz
1000 kHz
999.2 kHz
998.0 kHz
Answer: Option
Explanation:

Frequency present in the sidebands is equal to = fc ± fm, fc ± 2fm , fc ± 3fm .