off-hook to complete the dialing when the subscriber presses a button.

Invented by engineer August Kruckow, the dial tone was first used in 1908 in Hildesheim, Germany.

The Bell Telephone Manufacturing Company (BTMC) in Antwerp, Belgium, Western Electric's international subsidiary, first introduced a dial tone as a standard facility with the cutover of the 7A Rotary Automatic Machine Switching System at Darlington, England, on 10 October 1914. Dial tone

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