While still in school, I restored the spent battery pocket receiver rather primitive, but effective way. With pliers gently removed the graphite rod and filled the battery with water. Then waited until the water completely evaporated, put back stem — and battery-some time worked better than new.
Recommend to read
TORPEDO, GUN OR MINE?
Fighting submarines "against all" (and basically struggle with the poor merchant ships), turned around after only a few months after the outbreak of the First world war. For four years,...
THE TOOL HOLDER OF SCREW
If you don't have the special kit for fixing the abrasive wheel in the Chuck of a drill — assemble it from the available parts. Only need a screw, two large washers and nut. The circle...