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Communication Systems - Engineering

Q1:

If output power of a radio receiver is doubled, its volume is increased by __________ dB.

A 2

B 3

C 1

D -3

ANS:B - 3

Power output = 10 log Pout/Pin.
Where for an increase in volume by two times.
Pout = 2 Pin.

Therefore;
Increase in volume = 10 Log (2 Pin/Pin).
= 10 Log (2),
= 10 x 0.3,
= 3 dB.