Observation

     The expected answers were:

1.   (i)   In generic wireless communication system (including voice communication), the antenna at the transmitting end, radiates electromagnetic energy into space, and at the receiving end, captures and delivers electromagnetic energy to the receiver.                                                                                                   
   (ii)   The microphone, at the transmitter, converts voice into an electronic signal that  serves as the modulating signal.                                                                                  

(iii)  The local oscillator at the receiver, provides a carrier signal at the same  frequency as the carrier at the transmitter     

Question 5 required candidates to define some devices in communication systems in the first task and calculate the sidebands of an AM broadcast. Majority of the candidates, as reported, responded fairly well question 5 but for the definition of local oscillator to which virtually all candidates stated incorrectly.