ECELab.com Communications Electronics Auto-Reviewer
1) What does a demodulator do to the AM wave?a. recover the original modulating signal from it b. place the information signal into it c. encode the original modulating signal in it d. retrieve the carrier signal from it 2) Which of these is the imaginary outline of the peaks of the carrier signal?a. envelope b. carrier waveform c. odulated wave d. sidebands 3) Which of the following pertains to putting an original information signal directly on a medium ?a. modulation b. multiplexing c. carrier transmission d. baseband transmission 4) Microwaves are electromagnetic waves whose frequencies are over what limit?a. 100 MHz b. 1 GHz c. 10 GHz d. 100 GHz 5) Which of the following is done by a communications medium to the information signal it is carrying?a. modulation b. amplification c. attenuation d. decoding 6) Which of the following is used by light signals as medium for electronic communications?a. optical fiber b. free space c. both a and b d. neither a nor b 7) Which of the following converts the information into a form that matches the selected communications medium?a. receiver b. transmitter c. channel d. antenna 8) Which of the following refers to signal transmission without modulation?a. baseband communication b. distortionless transmission c. demodulation d. none of the above 9) If each party needs to take turns to transmit, what form of communication is being used?a. simplex b. half-duplex c. duplex d. dual-simplex 10) A continuously varying signal such as a video signal is what type of a signal?a. discrete b. digital c. analog d. transmitted
