What is an oscilloscope anyway ?
An oscilloscope is a diagnostic instrument that plots the amplitude of an electrical signal as it changes over time. Picture below shows the block diagram of an oscilloscope.
- Is the channel / DUT turned on?
- Is the waveform off the screen? Try adjusting the vertical position / scale.
- Is the instrument waiting for trigger? (Is it displaying “Ready”?) Verify trigger source; try adjusting the trigger level, forcing a trigger or switching to auto mode.
Aliasing: If the frequency of the signal on the screen seems too low, or it is difficult to get a stable waveform on the screen, adjust horizontal scale to increase the sample rate.
Unexpected measurement results: Verify that probe is compensated, verify measurement settings such as ref levels and gating, verify the probe attenuation.
No stable signal: Verify trigger source, trigger level.