@superwarp1 posted:YES, recharging can only be done with the Legacy #990 or #993 expansion pack. Better the use the 993. I would bet having the CAB3 and the 990 both powered at the same time would fight each other communicating to the remote.
Another option is to pick up a 9v battery charger. They're small, reliable, and available for under $10. That's what I did a couple of years ago, and I haven't looked back.
Or, you can just use alkaline batteries.