Which instrument is used to check the signal quality of a single-sideband radio transmission?

The oscilloscope is a key instrument used to check the signal quality of a single-sideband (SSB) radio transmission because it provides a visual representation of the waveform of the signal. By observing the waveform, an operator can assess various aspects of the transmission, such as amplitude, frequency stability, and distortion. This ability to visualize and analyze the signal is crucial for ensuring that the SSB transmission adheres to the necessary quality standards.

In the context of SSB transmission, the waveform will show the band of frequencies being transmitted and any unwanted artifacts that may indicate issues with the signal quality. By using an oscilloscope, technicians can troubleshoot problems, adjust signal parameters, and ensure that the transmitted signal is clear and free from interference.