In this case, as with most, you have to rely on how the panel is marked. What it looks like to me is the ports 37-40 are the trunk ports to the phone system. In other words, this is how your phone lines connect to the phone system so you can make calls.
The ports 44-48 are marked with phone numbers so I wouldguess that these are the phone lines from the phone company. Connecting the lines from th ephone company to the ports on the phone system makes it possible for you to make and receive calls.
The lower pannel, I would venture to guess since one says DSS, are the extension ports on the system, These are the ports that make the phones work, either the digital Toshiba phones, as you pictures, or analog phones you find in a typical house.
The other ports are probabaly all that cables that run throught the house.
Since you have several pieces to the door phone, the first step is to find out which does not work. Which is why I said to connect a regular analong phone, like a slime line, etc, to the "Phone" port on the viking and see if the phone rings when someone presses the door button.
Another thing you can try, since you said you only 2 phone lines, unplug the cable in port 40, and connect it to the "Phone" port on the viking. If it works, then line 4 on the phones should ring. Check the "Battery" switch and see if it is set to "ON". Per the directions it should he on when connected to a PBX trunk port.
As mentions, these door controler boxes can be connected to an analog exention port on the phone system, but it would be plugged into the "Line IN" port on the viking box.
