Things You'll Need
Instructions
Switch on the oscilloscope. Vary the vertical offset control to center the oscilloscope trace onto the 0V mark.
Plug the electrical signal into one of the oscilloscope inputs. There are normally two oscilloscope inputs and these are labeled "A" and "B." Switch on the relevant input by pressing the "A" or "B" button.
Modify the volts/division. This changes the vertical scale on the screen, and the number of volts each vertical division represents. Change the setting until the vertical component of the signal is within the screen limits.
Modify the time/division setting. The time/division changes the horizontal scale on the screen and the amount of time each horizontal division represents. Modify the setting until an oscillatory signal is clearly seen.
Measure the DC offset. Count the number of vertical divisions between the zero line on the oscilloscope and the centerof the oscillatory signal. Multiply the number of vertical divisions by the volts/division setting in order to obtain the DC offset.