The Tektronix TDS 2014 is a four channel Digital Storage Oscilloscope (DSO) with 8-bit analogue to digital converter. This document reports on the calibration of the equipment for voltage measurements. A precise multimeter was used to calibrate the DSO. The calibration was performed by applying various DC voltages to the DSO and comparing the measurement results reported by the DSO and the multimeter. We were able to establish a regression line for the multimeter and DSO readings, which could be used to estimate the real input voltage in future measurements recorded with the oscilloscope. We established there may be several factors which when altered could affect the outcome of a calibration. These factors include some of the DSO’s display settings such as the vertical position and vertical scale. Due to the results obtained we recommend that individual calibration tests must be conducted for different DSO settings.