A basic-configured electromagnetic energy harvester is proposed. It operates with varying magnetic induction at the center of a coil. Two magnets are located stable at the center of a coil having a spacer between them. Harvester does not give any elasticity problem with spring-free structure. The importance of coefficient of recovery is explained in theory of harvesters for the first time to our knowledge. The airgap formed by the spacer varies due to the vibration and this generates an electromotive force. It is proven that the proposed harvester generates a voltage amount V_rms = 2.41 mV and an electrical power P = 17 μW under the vibration frequency f = 60 Hz with 1 mm displacement. It corresponds to power density of 0.358 μW/cm³. Output voltages show a maxima with V_rms = 2.41 mV under R = 0.35 Ohm with a decaying trend with frequency. For R = 0.7 Ohm, higher voltages can be generated till 650 Hz. It is a superiority that this device has a very wide power harvesting regime from 2 Hz to 1.5 KHz. With such a wide characteristics, it can be used for many applications to harvest continuous energy from random vibrating ambient sources with its cheap and basic structure.