The existing approaches to ruggedizing inherently fragile and sensitive critical components of electronic equipment such as printed circuit boards (PCB) for use in hostile industrial and military environment are either insufficient or quite expensive. This Thesis addresses a novel approach towards ruggedizing commercially-off-the-shelf PCBs using a miniature wide-band dynamic absorber aimed at essential suppressing of the resonant responses of the original structure. The development of an optimisation technique is based on the dynamic properties of the original system, where the mass, stiffness and damping properties of the dynamic absorber are chosen in such a fashion to minimise the level of vibration experienced by the system. The optimisation procedure relies on the analytical solution and computational resources. The results of the proposed single-mode and full-mode approximation are proven experimentally under random vibration. Further study of the dynamic absorber is achieved by considering the system under swept-sine and shock excitations. This approach eventually focuses on the universal performance of the optimal dynamic absorber.