To use the oscilloscope, the probes of a channel are attached to ground (black) and the signal (red). With the signal at ground, the position (vertical/x) is adjusted with the position knob. This changes the location of 0V with respect to the vertical center of the screen. The Volts/Div button will adjust the vertical scale of the signal based on how many volts each square of division on the screen represents. A lower value will make the signal appear vertically larger with respect to the screen. The mode button determines which channel is displayed, if both are displayed at the same time, or if they are both added in an XY plot.
The horizontal position moves the entire image left or right. The Time/Div knob adjusts the amount of time that each division of the screen represents. A higher value will show more of the signal (make each period smaller) and a lower value will show less (make each period larger).
The trigger section adjusts what voltage will cause the oscilloscope to lock onto a still image of the signal. For example, a sine wave will show however many periods fit into the horizontal settings without moving if the trigger is set properly. The auto mode is most used, with the source for the trigger able to be changed with the switch next to that setting. External triggers are able to be used but aren’t for the purposes of this lab. The level knob sets the voltage at which the scope will trigger.
When turning the potentiometer down, the resistance will increase and therefore decrease the maximum voltage of the audio signal. This decreases the volume. When turned up, the resistance decreases and allows the voltage/volume to increase. The potentiometer can go between 0% and 100% of the original amplitude of the wave.