Abstract: A telephone switching network is disclosed having an announcement system coupled to a toll switching center.A plurality of short phrases are recorded in corresponding sectors of a disc store and announcements are assembled in real time by concatenating the appropriate phrases. Initial requests for announcements are sorted so that the reading heads seek across the disc in a straight line in a first direction to play back the recorded phrases. Any additional requests for playback received while the initial requests are being played back, are sorted in the opposite order for playback while the heads are driven in a second direction to their original position. All further requests are combined with any unfinished work for playback as the heads once again move in the first direction.The method of playing back while traversing the disc in both directions shortens the waiting interval for the listeners.

Abstract: A telephone network having a public announcement system is disclosed. Announcements are divided into message segments each of which is stored in a sector of a disc memory. When an announcement is activated, the message segments are loaded into a corresponding number of buffers for transmittal to calling customers. Each buffer will transmit the entire message, but in real time the buffers contain different message segments. Upon request for an announcement, the buffer containing the beginning message segment is selected to minimize holding time and customer waiting.