This paper suggests a retrofitting scheme for the accelerating magnet of the MGC-20 cyclotron owned by the Egyptian Atomic Energy Authority AEAEG. The main coil of this magnet and the accompanied corrector coils are to be equipped with new better quality power supplies based on a high performance Digital Signal Processor and highly efficient PWM converters. This paper can represent a partial proposal of an overall project to modernize and upgrade the replaceable cyclotron systems aiming at improving its performance and maximizing its economical and research profit. Digital simulation presented proves effectiveness and quality expected from the suggested scheme in adjusting magnet currents and consequently obtaining better results in final beam extraction and pointing to irradiated target.