Internal memory issue

After a long period away from lighting (last desk was a Sirius 24!) I've just bought a Leap Frog 24/48 referred to as 'original type' I think. Outwardly it is in pretty much pristine condition so I don't think it has had a hard life and the fact it has a flight case must have helped. Serial is 0073801 02460013 All seems well with it except for the fact that it doesn't appear to hold a show in the internal memory when power is switched off. The internal clock time and date is also lost which

Hi Andy, Welcome to the world of Frog, you'll love it! You will need a CR2032 battery (very common, get on the High Street). Place the desk on a table with the rear (the connector panel) facing you. Remove only 1 screw per side, it's the lowest screw in the curved rear metal silver side. The bottom panel will want to drop down, so support it. It's best to get some help as you will want to support the front panel whilst you access the PCB battery holder. You need to try to fli