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Alarm clock

technology Maturity 7-9 Next article →

An alarm clock is a tool made to alert people at a certain time. Its main job is to wake someone up from a nap or a night of sleep.

2010-07-20 Black windup alarm clock face
2010-07-20 Black windup alarm clock face

Most of these clocks use sound to get your attention. Some use bright lights or even vibrations to do the job. You can usually stop the noise by pressing a button or a handle. If you do not touch it, many clocks will turn themselves off after a while.

Alarm-iOS-26-3-1
Alarm-iOS-26-3-1

There are many different ways these clocks work. A classic mechanical clock uses a mainspring to create power. This spring turns gears that move a small hammer back and forth. The hammer hits bells to make a loud ringing sound.

Clock radio
Clock radio

In some electric clocks, a circuit uses magnetism to ring the bell. Digital clocks are different because they can make many kinds of noises. They can beep, buzz, or even play music and nature sounds like rain.

Early 2010s Philips Clock Radio with Apple dock & iPod Nano inserted (cropped)
Early 2010s Philips Clock Radio with Apple dock & iPod Nano inserted (cropped)

People have been looking for ways to wake up for a very long time. The Greek philosopher Plato may have used a large water clock to signal his lectures at dawn.

Istambul cokol1RB
Istambul cokol1RB

An inventor named Ctesibius made water clocks that could drop pebbles on a gong. In China, a monk named Yi Xing made a striking clock. Later, engineers like Zhang Sixun and Su Song added striking parts to astronomical clocks. Even in the 1400s, famous clockmakers like the Rainier family built beautiful clocks in Venice.

Clock radio
Clock radio

In the United States, Levi Hutchins made the first American alarm clock in 1787. He only made it to wake himself up at 4 am for work. Later, Antoine Redier became the first to patent an adjustable mechanical alarm in 1847. During World War II, factories stopped making clocks to focus on the war. This caused a shortage because old clocks were breaking. By November 1944, companies were allowed to start making them for people again.

Clock radio
Clock radio

Today, you can find alarms in almost every piece of technology. Most mobile phones and computers have alarm functions built right in. Some modern clocks are even smarter than they used to be. They use sensors to track your sleep stages so they can wake you up during light sleep.

Sleeptracker blue
Sleeptracker blue

This can help you feel less tired when you get up. Some people also use clock radios that play music or news to start the day.

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🖼️ Images & Media (7)
File:2010-07-20 Black windup alarm clock face.jpg
2010-07-20 Black windup alarm clock face.jpg
File:Istambul cokol1RB.JPG
Istambul cokol1RB.JPG
File:Clock radio.jpg
Clock radio.jpg
File:Morphy Richards Touch-Me clock radio.jpg
Morphy Richards Touch-Me clock radio.jpg
File:Early 2010s Philips Clock Radio with Apple dock & iPod Nano inserted (cropped).jpg
Early 2010s Philips Clock Radio with...
File:Alarm-iOS-26-3-1.png
Alarm-iOS-26-3-1.png
File:Sleeptracker blue.jpg
Sleeptracker blue.jpg
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