The telegraph key often directly made and broke the 2,000 volt supply.
From the en.wikipedia.org
The message was tapped out on an old-fashioned Morse telegraph key.
From the time.com
In my office at home, there's my dad's Vibroplex telegraph key.
From the suntimes.com
The larger balloons were used for carrying more weight, such as a telegraph key set and an additional man as an operator.
From the en.wikipedia.org
Regarding the Titanic story, some modern media historians question whether Sarnoff was at the telegraph key at all.
From the en.wikipedia.org
In conjunction with the latter, he also devised an automatic curb sender, a kind of telegraph key for sending messages on a cable.
From the en.wikipedia.org
On December 2, 1916, President Woodrow Wilson pressed the telegraph key that turned on the lights, successfully illuminating the statue.
From the en.wikipedia.org
Gray applied for a patent on a harmonic telegraph which consisted of multi-tone transmitters, each tone being controlled by a separate telegraph key.
From the en.wikipedia.org
Morse code was introduced in the 1840s and is used to encode each letter of the Latin alphabet and each Arabic numeral as a series of long and short presses of a telegraph key.