Subelement L: L – Installation, Maintenance & Repair— Topic 76: Oscilloscopes
Question 3-76L6
Element 3 (GROL)What instrument is used to check the signal quality of a single-sideband radio transmission?
Explanation
An oscilloscope is the primary instrument for visually checking the signal quality of an SSB transmission. It displays the waveform of the signal (voltage against time), allowing an operator to observe the modulation envelope. For SSB, quality issues often manifest as non-linearity, such as clipping or "flat-topping" of the peaks due to overdriving the transmitter or excessive audio gain. The oscilloscope clearly shows these distortions, indicating poor linearity and potential for generating unwanted splatter or harmonics.
A field strength meter (A) only measures the signal's strength, not its waveform or quality. A signal level meter (B) provides a numerical value for amplitude but cannot reveal distortion. A sidetone monitor (C) is an audio feedback for Morse code (CW) transmissions, entirely unrelated to SSB signal quality analysis.
Related Questions
3-76L4 What factors limit the accuracy, frequency response, and stability of an oscilloscope?3-76L5 An oscilloscope can be used to accomplish all of the following except:3-77L1 A(n) ____ and ____ can be combined to measure the characteristics of transmission lines. Such an arrangement is known as a time-domain reflectometer (TDR).3-77L2 What does the horizontal axis of a spectrum analyzer display?3-77L3 What does the vertical axis of a spectrum analyzer display?