How do I set up this Sakar corded wall mounted telephone. There is no model number on this phone. It has an LCD screen for date, time and number of calls - plus number of new calls. Receiver has buttons for up and down arrows, 'DEL' and 'DIAL'. There is also a lite for 'Ringer'. I have no idea how to program the date and time. Is this phone supposed plug into an answering machine?