[G6Tanuki]

Check the voltage on your NiCd packs before trying to charge them. Many modern chargers deliberately won't produce a significant output-current/voltage unless they detect a battery with a certain-degree of charge (a certain minimum voltage); this is a safety precaution to protect against failing battery-packs.

[I've got an old NiCd-powered portable drill here whose battery-packs are all-but-dead: the charger refuses to recognise them unless I hook an 18V supply to the battery for a few minutes before putting it on the charger - this puts just enough charge into the battery for it to be recognised by the charger - which then goes through a proper charge-cycle to the point where I can actually use the drill for a bit.]