y be two-way "boss-secretary" inter- coms. The "boss-secretary" intercoms are designed to emulate the older style button and buzzer type intercoms that worked very well. These intercoms took up two buttons on a multi-button tele- phone, one for the buzzer and the other for the intercom path on which the conversation between the boss and the secretary took place. Some intercoms have voice announce which enables the voice of the person who calls you on the intercom to speak to you and you to respond back, without having to lift the handset. Off-hook voice announce (less common) enables someone within your com- pany to speak to you through the speaker of your telephone while you are on an outside call using the handset. Dial intercoms are subgroups within a business telephone sys- tem, enabling members to call each other by dialing one or two digits without having to dial the complete extension number. The call may also ring on a separate button on the telephone, rather than on the button of the main extension number. Some business telephone system intercoms have paging, en- abling an announcement to be made from the speaker of every The Telecom Handbook - 43 THE PBX telephone at the same time (no more than 15 telephones simulta- neously on most systems.). Other systems enable access to a separate overhead paging system. Smaller business telephone systems (Key Systems) tend to have more flexibility in terms of the internal communications options than do the larger systems (PBXs). Incoming Calls Receiving a telephone call from either outside or inside the office: If someone is calling you, you answer by picking up the handset and saying "Hello." Some systems enable you to an- swer by just pressing a speaker button and saying "Hello" without lifting the handset. Other systems enable you to just say "Hello" without touching anything (seldom used but has application in environments where the recipient can't lift the receiver himself). Incoming telephone calls may provide the telephone number or name of the caller with C