Basic digital alarm clock without a radio. The mark in the top-left of the display indicates that the time is 4:00pm, not 4:00am

A digital clock is a type of clock that uses digital electronic methods of keeping time. Image File history File linksMetadata Download high resolution version (2500x1870, 761 KB) Summary Digital alarm clock of a basic design without a radio. ... Image File history File linksMetadata Download high resolution version (2500x1870, 761 KB) Summary Digital alarm clock of a basic design without a radio. ... The massive clock on the Clock Tower of the Palace of Westminster, London (commonly known as Big Ben, although Big Ben is the bell inside - the picture is St Stephens Tower). ... This Article does not cite any references or sources. ... A pocket watch, a device used to tell time Look up time in Wiktionary, the free dictionary. ...

Construction

Digital clocks typically use the 50 or 60 hertz oscillation of AC power or a crystal oscillator as in a quartz movement to keep time. A digital clock typically displays a numerical hour range of 0–23, or 1–12 (with an indication of AM or PM), although digital versions of analog-style faces exist. MHZ redirects here. ... Usually hidden to the unaided eye, the blinking of (non-incandescent) lighting powered by AC mains is revealed in this motion-blurred long exposure of city lights. ... A crystal oscillator is an electronic circuit that uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency. ... A digital system is one that uses discrete values (often electrical voltages), especially those representable as binary numbers, or non-numeric symbols such as letters or icons, for input, processing, transmission, storage, or display, rather than a continuous spectrum of values (ie, as in an analog system). ... This article needs additional references or sources for verification. ...

Displays

Digital clock's display changing numbers.

An LCD battery operated clock without alarm.

To represent the time, most digital clocks use a seven-segment LED, VFD, or LCD display for each of four digits. They generally also include other elements to indicate whether the time is AM or PM, whether or not an alarm is set, and so on. Image File history File links Metadata Size of this preview: 800 × 281 pixelsFull resolution (2560 × 900 pixel, file size: 305 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Metadata Size of this preview: 800 × 281 pixelsFull resolution (2560 × 900 pixel, file size: 305 KB, MIME type: image/jpeg) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Metadata Size of this preview: 800 × 420 pixelsFull resolution (2084 × 1094 pixel, file size: 481 KB, MIME type: image/jpeg) My LCD clock with LED backlight. ... Image File history File links Metadata Size of this preview: 800 × 420 pixelsFull resolution (2084 × 1094 pixel, file size: 481 KB, MIME type: image/jpeg) My LCD clock with LED backlight. ... External links LEd Category: TeX ... A vacuum fluorescent display (VFD) is a type of display used primarily on consumer-electronics equipment such as video cassette recorders. ... LCD redirects here. ...

Setting

A premium digital clock radio with digital tuning.

A basic digital clock radio with analog tuning.

One notorious drawback to digital clocks is the difficulty of setting the time in some designs. Most digital clocks flash 12:00 by default when first powered on and, since the clock is often not a critical function in many electronic devices, people often allow them to display this default. ImageMetadata File history File links Download high resolution version (2500x2683, 1215 KB) Summary Digital clock of a premium design. ... ImageMetadata File history File links Download high resolution version (2500x2683, 1215 KB) Summary Digital clock of a premium design. ... Image File history File linksMetadata Download high-resolution version (2500x1667, 730 KB) Digital clock of a basic design commonly found in hotels. ... Image File history File linksMetadata Download high-resolution version (2500x1667, 730 KB) Digital clock of a basic design commonly found in hotels. ...

Moreover, since they run on electricity and have no permanent memory, digital clocks must be reset every time they are moved or the power is cut off. This is a particular problem with alarm clocks, since a power outage during the night usually results in the clock failing to trigger the alarm in the morning. Lightning strikes during a night-time thunderstorm. ... A digital clock radio with digital tuning A wind-up, spring-driven alarm clock A basic digital clock radio with analog tuning An alarm clock is a clock that is designed to make an alert sound at a specific date and/or time. ... Power Outage is an episode of The WB drama series, Charmed. ...

To reduce the problem, they often incorporate a battery backup to maintain the time during power outages. More recently, some devices incorporate a method for automatically setting the time, such as using a broadcast radio time signal from an atomic clock, getting the time from an existing satellite television or computer connection, or by being set at the factory and then maintaining the time from then on with a quartz movement powered by an internal rechargeable battery. Symbols representing a single Cell (top) and Battery (bottom), used in circuit diagrams. ... A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day. ... Chip-scale atomic clock unveiled by NIST An Atomic Clock is a type of clock that uses an atomic resonance frequency standard to feed its counter. ... Satellite television is television delivered by way of communications satellites, as compared to conventional terrestrial television and cable television. ... The NASA Columbia Supercomputer. ...

Uses

A digital clock built into an oven.

• Digital clocks are very small, useful, and inexpensive. For these reasons, they are often incorporated into virtually every electronic device. Most commonly, digital clocks are incorporated into bedside alarm clock radios, but they are also found in televisions, microwave ovens, standard ovens, watches,computers and cell phones.

• In the 1980s and 1990s, digital clocks were standard on most automobiles. However, the fashion is slowly leaning towards analog clocks, which was the first style of clock to be used in automobiles.

ImageMetadata File history File links Download high resolution version (2500x1239, 599 KB) Summary Digital clock in an oven. ... ImageMetadata File history File links Download high resolution version (2500x1239, 599 KB) Summary Digital clock in an oven. ... A digital clock radio with digital tuning A wind-up, spring-driven alarm clock A basic digital clock radio with analog tuning An alarm clock is a clock that is designed to make an alert sound at a specific date and/or time. ... It has been suggested that this article be split into articles entitled Microwave oven and Microwave heating. ... Oven depicted in a painting by Millet An oven is an enclosed compartment for heating, baking or drying. ... Russian Poljot Siberia model finished movement viewed through crystal back For other uses, see Watch (disambiguation). ... Car redirects here. ... A wall clock A clock (from the Latin cloca, bell) is an instrument for measuring time. ...

History

Digital clocks were invented in 1956 ( although one can be seen in the film The Black Cat from 1934) and became more popular as microchips and LEDs became cheaply available. Into the 1970s digital clocks were typically mechanical, where a synchronous AC motor is used to turn parts of the mechanism to display the changing time. Didital Clocks can be portable Year 1956 (MCMLVI) was a leap year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... The Black Cat is a 1934 horror film that became Universal Pictures biggest box office hit of the year. ... Integrated circuit of Atmel Diopsis 740 System on Chip showing memory blocks, logic and input/output pads around the periphery Microchips with a transparent window, showing the integrated circuit inside. ...

Analog clock with digital display

This type of clock is a variant of the digital clock that displayed time digitally but kept the time mechanically. Some old-fashioned clocks with digital displays really keep track of the time in an analog fashion. ...

External links

• How Digital Clocks Work