The vertical axis of a spectrum analyzer indicates which quantity?

Get ready for the FCC General Radiotelephone Operator License (GROL) exam. Study with flashcards and multiple choice questions, each with hints and detailed explanations. Prepare effectively for your licensing test!

Multiple Choice

The vertical axis of a spectrum analyzer indicates which quantity?

The key idea here is that a spectrum analyzer displays how much energy exists at each frequency. In this view, the horizontal axis is frequency, showing where those components lie, and the vertical axis represents the strength of each component, i.e., its amplitude (often shown in dB or dBm). So the vertical scale corresponds to amplitude because the device is mapping signal strength across frequencies rather than showing time evolution or a phase relationship. Time isn’t represented in this display (that would be on a time-domain oscilloscope), and a standard magnitude spectrum emphasizes amplitude; phase information isn’t shown on the main trace, though some analysers can provide a separate phase plot if needed.

The key idea here is that a spectrum analyzer displays how much energy exists at each frequency. In this view, the horizontal axis is frequency, showing where those components lie, and the vertical axis represents the strength of each component, i.e., its amplitude (often shown in dB or dBm). So the vertical scale corresponds to amplitude because the device is mapping signal strength across frequencies rather than showing time evolution or a phase relationship. Time isn’t represented in this display (that would be on a time-domain oscilloscope), and a standard magnitude spectrum emphasizes amplitude; phase information isn’t shown on the main trace, though some analysers can provide a separate phase plot if needed.

More practice questions