I don't think that is possible. What does the user manual say? What is the model number?
Can I use my DECT6 phone as a door intercomm? My plan is to fix one out of 4 handsets at the door so that the visitor can press a single button at the door to call any one of the remaining 3 phones inside the house. Presently it can be done by selecting on screen " Menu/INT/handset ID". Which is not practical. Can I create a dedicated key for intercomm without going thro' Menu. Can any one enlighten me?