Yes, please take this suggestion seriously! This is especially true for the Pro-106 and related family of scanners. The charging circuit for this scanner and its siblings is extremely poorly designed and can fail catastrophically to where your scanner would be finished within a matter of minutes. I have personally experienced this after plugging in my scanner for only several minutes one day for what I thought was a quick top off charge as I have it set to only charge for 1 hour at a time. I was lucky enough to have been around so it only melted my yellow battery holder and slightly warp my battery compartment to where the battery door barely stays in. I am not sure of my memory is correct on the details, but it is possible that the scanner was even turned off at the time when I had it plugged into power.Never charge the batteries in the scanner, as it's only a timed charger and doesn't shut off when the batteries are properly charged. With every model of scanner there been reports of the batteries getting very hot and destroying the scanner.
Going forward you wouldn't want to lose the scanner with battery charging. Get a good quality charger and two or three sets of batteries. This way will always have a charged set ready to go.
Just an FYI doing that only affects when the low battery warning icon is shown or flashes. It does not shut off the internal battery charge circuit.To change battery type: Press PGM. Press F3. Press the down key until the middle line of the display shows "Battery Alkaline". Press left or right keys until you select the type of battery you have installed (Alkaline, Ni-Cd, Ni-MH). Press F1 to save your battery settings.