A simple and novel method for transforming a uniform fiber grating into a linearly chirped grating is presented. This method permits independent tuning of the chirp degree and the central wavelength of the fiber gratings. It is demonstrated experimentally that the chirp degree of a 100 mm long uniform grating can be increased up to 0.5 nm/cm and its central wavelength can be independently tuned by 0.7 nm. A transmission experiment for compensating the dispersion of a standard single mode fiber (G652) over a distance of 100 km of a 25 ps input signal in the 1550 nm windows was successfully demonstrated using such a tunable chirped grating of 10 cm in length.