Telephone Switchboard - History

History

The first telephones in the 1870s were rented in pairs which could only talk to each other, but the example of a central exchange was soon found to be even more advantageous than in telegraphy. Small towns typically had the switchboard installed in the operator's home so that he or she could answer calls on a 24 hour basis. In 1894, New England Telephone and Telegraph installed the first battery-operated switchboard on January 9 in Lexington, Massachusetts.

Early switchboards in large cities usually were mounted floor to ceiling in order to allow the operators to reach all the lines in the exchange. The operators were boys who would use a ladder to connect to the higher jacks. Late in the 1890s this measure failed to keep up with the increasing number of lines, and Milo G. Kellogg devised the Divided Multiple Switchboard for operators to work together, with a team on the "A board" and another on the "B." These operators were almost always women until the mid-1960s when men were once again hired. Cord switchboards were often referred to as "cordboards" by telephone company personnel. Conversion to Panel switch and other automated switching systems first eliminated the "B" operator and then, usually years later, the "A". Rural and suburban switchboards for the most part remained small and simple. In many cases, customers came to know their operator by name.

As telephone exchanges converted to automatic (dial) service, switchboards continued to serve specialized purposes. Before the advent of direct-dialed long distance calls, a subscriber would need to contact the long-distance operator in order to place a toll call. In large cities, there was often a special number, such as 112 or 211, which would ring the long-distance operator directly. Elsewhere, the subscriber would ask the local operator to ring the long-distance operator.

When calling long distance, the calling party would give the name and city of the person desired, and the operator would advise the calling party to hang up and wait for the call to be completed. Each toll center had only a limited number of trunks to distant cities, and if those trunks were busy, the operator would try alternative routings through intermediate cities. The operator would plug into a trunk for the distant city, and the inward operator would answer. The inward operator would obtain the number from the local information operator, and ring the call. Once the called party answered, the local operator would advise him or her to stand by for the calling party, whom she'd then ring back. The calling party's long distance operator would time the call for billing purposes.

In the 1940s, with the advent of dial pulse and multi-frequency operator dialing, the operator would plug into a tandem trunk and dial the NPA (area code) and operator code for the information operator in the distant city. For instance, the New York City information operator was 212-131. If the customer knew the number, and the point was direct-dialable, the operator would dial the call. If the distant city did not have dialable numbers, the operator would dial the code for the inward operator serving the called party, and ask her to ring the number.

In the 1960s, once most phone subscribers had direct long-distance dialing, a single type of operator began to serve both the local and long distance functions. A customer might call to request a collect call, a call billed to a third number, or a person-to-person call. All toll calls from coin phones required operator assistance. The operator was also available to help complete a local or long-distance number which did not complete. For example, if a customer encountered a reorder tone (a fast busy signal), it could indicate "all circuits busy," or a problem in the destination exchange. The operator might be able to use a different routing to complete the call. If the operator could not get through by dialing the number, she could call the inward operator in the destination city, and ask her to try the number, or to test a line to see if it was busy or out of order.

Cord switchboards used for these purposes were replaced in the 1970s and 1980s by TSPS and similar systems, which greatly reduced operator involvement in calls. The customer would, instead of simply dialing "0" for the operator, dial 0+NPA+7digits, after which an operator would answer and provide the desired service (coin collection, getting acceptance on a collect call, etc.), and then release the call to be automatically handled by the TSPS.

Before the late 1970s and early 1980s, it was common for many smaller cities to have their own operators. An NPA (area code) would usually have its largest city as its primary toll center, with smaller toll centers serving the larger secondary cities scattered throughout the NPA. TSPS allowed telephone companies to close smaller toll centers and consolidate operator services in regional centers which might be hundreds of miles from the subscriber.