D-Link DPH-50U manual

STEP 4: Connect a standard telephone handset to the DPH-50U phone jack using a telephone cable as shown below

STEP 5: Connect a telephone cable between the DPH-50U line jack and a wall jack as shown below. Note that this is only required for making regular phone calls or for forwarding Skype calls to your mobile (or other off-site) phone or for toll bypass applications.