Door intercom system has living telephone equipment with mobile radio module for making mobile connection with mobile telephone

摘要

Door intercom system has a living telephone equipment (16) with a mobile radio module (26) for making a mobile connection with a mobile telephone (28). The system has a door station (10) with a doorbell button (12) and speaker/microphone unit (14) for speaking and hearing activity. Living telephone equipment has a calling tone speaker (18) for signaling of activity of bell button.