What condition may cause a significant loss...

Question 1 / 2707051rWkoB7aMOiCWNNWyN7

Question 1 of 2707051rWkoB7aMOiCWNNWyN7

What condition may cause a significant loss in VHF receiver sensitivity?

Question 1 of 27070

What condition may cause a significant loss in VHF receiver sensitivity?

🔍 Key Concepts

• Receiver sensitivity and what it means in practical terms • How internal noise or undesired signals affect a receiver’s ability to hear weak signals • The effect of impedance and coax type on VHF performance compared to internal receiver faults

💭 Think About

• Which choice describes a condition inside the receiver that would make it harder to detect weak incoming signals? • Is a strong internal signal or a very weak internal signal more likely to mask or interfere with the desired weak signal? • Does simply changing from 75-ohm to 50-ohm cable usually cause a significant loss of sensitivity in a properly matched VHF system?

✅ Before You Answer

• Identify which option directly affects the signal level relative to internal noise at an intermediate frequency (IF) stage. • Distinguish between a measurement condition (like a voltmeter reading) and an actual fault or interference condition inside the receiver. • Ask whether the described condition would realistically cause the receiver to miss weak VHF signals that it should otherwise hear.

Question 1 of 27070

What condition may cause a significant loss in VHF receiver sensitivity?

A reading of 9.6 when a voltmeter is connected between the positive side of the radio 's DC line and ground .

The presence of a -90dbm signal measured at the 2nd IF output with the receiver tuned to the desired input frequency.

An internal signal that is very weak in comparison to the desired signal at the output of the second IF stage.

Replacing (75 ohm) RG-59/U coaxial transmission line with a (50 ohm) RG-8/U or LMR-400 Ultraflex cable.

Question 1 / 2707051rWkoB7aMOiCWNNWyN7

Question 1 of 2707051rWkoB7aMOiCWNNWyN7

What condition may cause a significant loss in VHF receiver sensitivity?

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Question 1 of 27070

What condition may cause a significant loss in VHF receiver sensitivity?