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Community Dial Exchanges

Manual switchboards in rural communities are being replaced by dial systems. These small offices, called community dial offices, may be left unattended, yet are ready to operate at all times. If the services of an operator are required by a subscriber, it is necessary only to dial "0" to obtain the toll operator at the operator office. This office is usually the nearest attended office and may handle all the operator services for several community dial offices.

A community dial office usually has a large number of party lines. These lines require either dialed code ringing or harmonic ringing to signal the desired party. Means must be provided for one party to call another party on the same line. A subscriber in dialing another party on the same line will ordinarily receive busy tone and the called line will not be rung. Reverting call equipment is used to overcome this. The calling subscriber dials either the directory number of the desired party or a special number. Busy tone is received after dialing this number; then, the calling subscriber replaces the handset, and the called station will be rung. Also the calling party's bell will be rung. When the called party answers the ringing will stop, thus indicating to the calling party that the call has been answered. The first person lifting the receiver on that line will cause the ringing to be cut off.



Last Update: 2011-05-30