My TT Pro 500 needs a new battery pack. Do I need to use a TT pack or can I go to Radio Shack and get one. It says on the battery to only use TT Battery pack. I figured that might just be a sales pitch
Charge your unit for at least 14 hours. Unplug unit and remove the batteries for 5 minutes. Replace your batteries and recharge for another 5 minutes.
What happens to some of these units is, if they are not charged monthly they can loose the chips memory and must be reset.
If your unit is not taking a charge give it a try first before replacing the batteries.