Batteries are easy enough to replace, available from RS electronics.Green one top left turns it on ( need to hold it down for a few seconds) then the others work menu functions on the screen next to them. You may need to charge it up first, and if the battery won’t hold charge you’ll need to phone Victor
Didn’t know that. How do you get in? Mine looks very much sealed for lifeBatteries are easy enough to replace, available from RS electronics.