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Almon Brown Strowger and the Invention of the Automatic Telephone Exchange

ben profile image Ben Halpern ・1 min read

I found this story fascinating and wanted to share...

Almon Brown Strowger was an undertaker and was losing business to a competitor a competitor's wife, working as a telephone operator, was routing calls away from Strowger to their funeral home business.

Almon Brown Strowger was an American inventor who gave his name to the Strowger switch, an electromechanical telephone exchange technology that his invention and patent inspired.

One thing lead to another and Strowger invented the Automatic Telephone Exchange in 1889, essentially putting an end to the telephone operator altogether.

Automatic exchanges, or dial service, came into existence in the early 20th century. Their purpose was to eliminate the need for human switchboard operators who completed the connections required for a telephone call. Automation replaced human operators with electromechanical systems and telephones were equipped with a dial by which a caller transmitted the destination telephone number to the automatic switching system.

A telephone exchange automatically senses an off-hook condition of the telephone when the user removes the handset from the switchhook or cradle. The exchange provides dial tone at that time to indicate to the user that the exchange is ready to receive dialed digits. The pulses or DTMF tones generated by the telephone are processed and a connection is established to the destination telephone within the same exchange or to another distant exchange.

The exchange maintains the connection until one of the parties hangs up. This monitoring…

I'm sure elements of this story have been glorified in history, but it's a fascinating tale with a lot of modern corollaries.

Discussion (2)

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rehmatfalcon profile image
Kushal Niroula

He was not happy with the plugin so he made his own. Sounds familiar 😉

lbonanomi profile image

Strowger's idea, in the form of the Step by Step switch and the Community Dial Office could be found in service until at-least the early 1990s in certain more out of the way places.

"essentially putting an end to the telephone operator altogether."

Not even close, sir. Manual switchboards were the rule in private establishments like hotels and hospitals and quite normal in lower-traffic areas well into the 20th century. Bryant Pond, Maine was a manual switchboard until 1982.