EPR investigations on DPPH and Manganese Chloride were successful and matched the theory concerning EPR and ESR that is currently accepted. There were some anomalies but there were similarities between the accepted values and the experimental values. The g-values calculation was much more concrete and simple with the help of the simplified formula, using only the microwave frequency and the centre field, and the scalar constant. The instrument used for the experiment was complex, combining many uses to give readings relevant to EPR spectroscopy. The g-values for both the DPPH and the MnCl2 experiments were quite close to the theoretically calculated g-values, which hence proves that the experiment was accurate and successful.