button to activate the backlight for roughly 5 seconds. For a "permanent on" display, use the DC power adapter. Setting Time and Date Enter Setting Mode : Press and hold the key for 3 seconds. Adjust Values buttons to change digits. Navigate Fields : Short-press to cycle through the setting order: Hour > Minute > Year > Month > Day
Open the battery cover on the rear and insert 3x "AAA" batteries (not included).