Saturday, October 2, 2010

Q8

Briefly explain the operation of a digital clock?

2 comments:

  1. A digital clock is a type of clock that displays the time digitally i.e. in cyphers, as opposed to an analog clock, where the time is displayed by hands. Usually, digital clocks are associated with electronic drives, but the "digital" description refers only to the display, not to the drive mechanism. (Analog clocks are driven mechanically or electronically.) The biggest digital clock is the Lichtzeitpegel ("Light Time Level").
    Digital clocks typically use the 50 or 60 hertz oscillation of AC power or a 32,768 hertz crystal oscillator as in a quartz clock to keep time. Most digital clocks display the hour of the day in 24 hour format; in the United States and a few other countries, a more commonly used hour sequence is 12 hour format (with some indication of AM or PM). Some clocks can display either time mode according to the owner's preference. Emulations of analog-style faces often use an LCD screen, and these are also sometimes described as "digital".A basic digital clock radio with analog tuning.
    Some people find difficulty in setting the time in some designs of digital clocks. Therefore in electronic devices where the clock is not a critical function, often they are not set at all, displaying the default after powered on, 00:00 or 12:00.
    Since they run on electricity, digital clocks must be reset every time the power is cut off. This is a particular problem alarm clock with that have no "battery" backup, because even a very brief power outage during the night usually results in the clock failing to trigger the alarm in the morning.
    To reduce the problem, many devices designed to operate on household electricity incorporate a battery backup to maintain the time during power outages and during times of disconnection from the power supply. 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.

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  2. a digital clock operates basically on counters driven by a particular frequency of certain mhz....

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