Q.1. Sky wave communication is based upon
(A) reflection by ionosphere
(B) absorption by ionosphere
(C) transmission through ionosphere
(D) None of these
Ans :- (A)
Q.2. The process opposite to modulation is
(A) demodulation
(B) transmission
(C) remote sensing
(D) fax
Ans :- (A)
Q.3. A net work within an institution is known as
(A) Internet
(B) local arca network (LAN)
(C) computer’s system
(D) Computers network
Ans :- (B)
Q.4. Which frequency range is used for TV transmission ?
(A) 30 Hz – 300 Hz
(B) 30 kHz – 300 kHz
(C) 30 MHz – 300 MHz
(D) 30 GHz -300 GHz
Ans :- (C)
Q.5. The range of frequencies allotted for FM radio is
(A) 88 to 108 kHz
(B) 88 to 108 MHz
(C) 47 to 230 kHz
(D) 47 to 230 MHz
Ans :- (B)
Q.6. The device that is ‘duplex’ is
(A) TV
(B) mobile
(C) both ‘A’ and ‘B’
(D) None of these
Ans :- (B)
Q.7. In optical fibre communication light source is
(A) Zener diode
(B) laser or LED
(C) photodiode
(D) sodium lamp
Ans :- (B)
Q.8. Which is not an example of analog communication?
(A) FAX
(B) telegraphy
(C) Radar
(D) telex
Ans :- (A)
Q.9. For radio waves ionosphere acts as a
(A) Rarer medium
(B) denser medium
(C) free space
(D) dielectric medium
Ans :- (A)
Q.10. The maximum percentage of deformationless modulation is
(A) 100%
(B) 75%
(C) 110%
(D) 50%
Ans :- (A)
Q.11. Which of the following is not a transducer?
(A) land speaker
(B) amplifier
(C) microphone
(D) All the above
Ans :- (B)
Q.12. Broadcasting antennas are generally
(A) omnidirectional type
(B) vertical type
(C) horizontal type
(D) None of these
Ans :- (B)
Q.13. The range of TV transmission can be increased by using
(A) small antennas
(B) tall antennas
(C) radio waves
(D) None of these
Ans :- (B)
Q.14. The essential components of the communication system are/is
(A) transmitter
(B) channel
(C) receiver
(D) All of above
Ans :- (D)
Q.15. Name the device which can represent digital data by analog signals and vice-versa.
(A) Modulation
(B) Demodulation
(C) Modem
(D) None of these
Ans :- (C)