There are various techniques and technologies of connecting a phone into a paging system. The way of setting up a phone paging system depends upon the existing phone system and the facilities required.
The most cost-effective way of setting up a paging system is by using the paging port output on the telephone. This output is typically an audio line level signal which can be wired into the audio input on the PA amplifier via a low-cost barrier interface unit. The barrier interface unit provides the electrical isolation of two systems. This is beneficial because an electrical fault on one system won’t cause any damage to the other. Thus, a user can just pick up the phone handset and dial the facility code on the system that is usually a star command. A live page announcement can be made, and a PA call can be ended by hanging up on the phone.
Another method of connecting a phone paging system is by using a phone paging extension interface. This is a device that can be plugged into an interface phone extension and then can be connected to a public address system. The designated extension number can be dialed for the paging interface, and then it makes the announcement as soon as the call is picked up by the phone paging extension interface device.
There are a lot of advantages of using a phone paging extension interface than a paging port output: