# Tco 3 an am receiver s local oscillator is tuned to

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Question 2.Question :(TCO 3) An AM receiver s local oscillator is tuned to 1195KHz and is using high-side injection. What would be the frequency of the desired carrier?Student Answer: 170KHz285KHz740KHzExplanation:For high side injection fLO= fC+ 455 KHz, fC= fLO- 455 = 1195 -455 = 740 KHz 1650KHz Instructor Points Received: 0 of 5 Comments: Question 3. Question :(TCO 3) An AM receiver is tuned to receive a carrier frequency of 1040KHz and is using high-side injection. What would be the frequency of the image frequency?
Student Answer: 1950KHz Instructor f IM = f C + 2(455) = 1040 + 2(455) = 1950 KHz Points Received: 5 of 5 Comments: Question 4.Question :(TCO 3) An AM receiver is tuned to receive a carrier frequency of 1370KHz and is using low-side injection. What would be the image frequency?Student Answer: 2280KHz Instructor f IM = f C - 2(455) = 1370 - 2(455) = 460 KHz Points Received: 5 of 5 Comments: Question 5.Question :Referring to the spectrum analyzer display below for the AM signal, what is the modulation frequency? Student Answer: 20KHz
Instructor Points Received: 10 of 10 Comments: Question 6.Question :Based on information from previous question, modulator factor = ______Student Answer: 0.10.20.40.5None of the above.Explanation:0.4 Instructor Points Received: 0 of 10 Comments: Question 7.Question :Continue from previous question, carrier frequency = ______Student Answer:20KHz ()40KHz () )
80KHz ( ) 100KHz ( ) Instructor Points Received: 10 of 10 Comments: Question 8. Question : In AM Superheterodyne receiver, IF Amps are lowpass filters and cutoff frequency is set at 455KHz. Student Answer: True False Instructor Explanation: bandpass Points Received: 0 of 10 Comments: * Times are displayed in (GMT-07:00) Mountain Time (US & Canada) Grading Summary These are the automatically computed results of your exam. Grades for essay questions, and comments from your instructor, are in the "Details" section below. Date Taken: 5/28/2016 Time Spent: 17 min , 03 secs Points Received: 20 / 50 (40%) Question Type: # Of Questions: # Correct: True/False 2 0 Multiple Choice 4 3 Grade Details - All Questions Question 1. Question : (TCO 4) From the spectrum analyzer display shown below, determine the total bandwidth needed to transmit that signal. Student Answer: 15KHz
60KHz 90KHz 120KHz Instructor Explanation: From the given scale, each division is 160/4 = 40 KHz. The signal occupies a little more than two divisions and therefore the required BW is about 90 KHz. Points Received: 0 of 10 Comments: Question 2. Question : (TCO 4) From the spectrum analyzer display below, determine the modulation frequency. Student Answer: 5KHz 15KHz 30KHz 90KHz 200KHz Instructor Explanation: Modulation frequency is the difference between any two consecutive frequencies.
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