If a flash isn't used for several weeks, the capacitor loses its ability to hold a charge effectively. With good batteries installed, turn the unit on and wait four or five minutes. Then fire the flash six to eight times, waiting about twenty seconds between each burst. Finally, with the flash fully charged, turn it off and put it away. Do this about once a month.
Nicad batteries require special care and feeding.
Just follow the instructions that come with them. Steve Traudt teaches photography at Mesa State College in Colorado. He also runs a number of his own workshops. Inc. Copyright 1995-2000. Inc. All Rights Reserved.