Party line (telephony)
From Wikipedia, the free encyclopedia
In telephone systems, a party line (also multiparty line or Shared Service Line) is an arrangement in which two or more customers are connected directly to the same local loop. Prior to World War II in the United States, party lines were the primary way residential subscribers acquired local phone service. All the subscribers that share the party line have the same phone number. When a call is received at that number, all of the subscribers phones will ring. When the line is in use, if any of the other subscribers to that line pick up the phone, they can hear and participate in the conversation. In order to distinguish one line subscriber from another, operators developed different rings for the lines so that if the call was for the first subscriber to the line, the ring would follow one pattern, if the call was for the second subscriber, the ring would sound another way, and so on. [1] [2]
Party lines remain primarily in rural areas where local loops are long. Privacy is limited and congestion often occurs. In isolated communities, such as the Pitcairn Islands, party lines have been used without any direct connection to the outside world.
Party Lines are not suitable for internet access. If one customer is using dial up, it will jam the line for every customer and they cannot be used with ADSL.
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[edit] Railways
Party lines used to be common on railways, where numerous telephones were connected to a single pair of wires. Usually a long ring of many turns of the handle would alert the exchange that a connection was required to another destination. The problem of selective calling was also solved by a mechanical device which could selectively ring one or a group of stations.
[edit] Party Lines Still In Existence
There is still a community linked by party line in the mountains above Los Angeles. Big Santa Anita Canyon, near Sierra Madre, CA, has 81 rustic cabins, a group camp and a pack station that all communicate by magneto-type crank phones. One ring is for the pack station, two rings for the camp and three rings means all cabins pick up.
Check out the website for Adams' Pack Station[1] for more information.
