This circuit is used to clear the nicad battery internal shorts in nickel - cadmium batteries. To operate this circuit , connect AC cable , then connect a Nicad battery to the output + , - and press PB (push button) for three second. See circuit below :
Electronic Circuit is a good site for hobbyist also who would like to try DIY because it shared good circuits. If you have a personalized circuit requirement you may feel free to request it through the comment box or contact me.