This paper deals with the experimental validation of equalization technique of RC-line degradations based on a negative group delay (NGD) active circuit. The feasibility of this method is illustrated by brief theoretical recalls. Formulas permitting the synthesis of this NGD circuit according to the RC-line parameters are proposed. Then, the analytical predictions are verified by experimental results, which also provide evidence the efficacy of the technique for prototypes in planar hybrid technology. So, for an input square-wave pulse of 25 Msym/s-rate, the rise-time and the propagation delay of the regarded RC-circuit were respectively reduced by 71.4% and 86.4%. As expected, the recovered measured signal shows enhancement of both the raising and trailing edges. Finally, the main benefits provided by this technique compared to the use of repeater are discussed.