What is the image frequency if the normal...

Question 1 of 27070mWs4NZ6m6R0ychbZWkey

What is the image frequency if the normal channel is 151.000 MHz, the IF is operating at 11.000 MHz, and the LO is at 140.000 MHz?

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Question 1 of 27070

What is the image frequency if the normal channel is 151.000 MHz, the IF is operating at 11.000 MHz, and the LO is at 140.000 MHz?

🔍 Key Concepts

• Superheterodyne receiver operation and how the local oscillator (LO), intermediate frequency (IF), and received (RF) frequency are related • Formula for image frequency: how far the image is from the LO compared to the desired RF signal • Difference between high-side and low-side injection of the LO relative to the received channel

💭 Think About

• First, write the basic relationship between LO, RF (normal channel), and IF for this receiver. Is the LO higher or lower than the normal channel in this problem? • Once you know how LO, RF, and IF are related, think about where the image must be so that it produces the same IF when mixed with the LO. • Compare how far the normal channel is from the LO and then see where another frequency at the same offset (on the opposite side) would fall.

✅ Before You Answer

• Confirm whether the receiver is using low-side or high-side LO injection based on the numbers given (151 MHz vs 140 MHz). • Check that the difference between the LO and the normal channel equals the given IF (11 MHz). • Compute the frequency on the other side of the LO at the same IF offset and make sure it matches one of the choices exactly.