 Round Clock 
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Square Clock
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Eight Angle
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Picture Frame Clock
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Premium Clock
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Spare Parts
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Example Picture
 Clock Package
Backside
Clock Package Box (Open)
Clock Package Box (Close)
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( ภาษาไทย..คลิกที่นี่ ) 
The " Roma" classic clock shop with quality time for you.
Presents by:
M. Pheeraphant Co.,Ltd.
44/203-204 Ramintra 65 Bangken Bangkok Thailand 10230
Tel. 66 2 946 5118 , 66 2 946 5119
Fax. 66 2 946 5120
Email: romaclock@hotmail.com
" The quality clock but cheap price "
Enjoy a delightfully refreshing step back in "time" as you leisurely view a diverse selection of quality classic clocks from an impressive inventory.
" We are the quality clock industry with the modern and quality tools for produce the Roma classic clock style as Round Clock, Sqare Clock , Eight Angle Clock , Picture frame Clock and Premium Clock. "
" We sell the Roma classic clock very cheap price or the name of " the industry special price " when you buy lot of products. "
" We sell the Roma classic clock in Thailand and oversea so we sell parts of clock for your choice "
 Just call : 66 2 946 5118 , 66 2 946 5119
    
 
 
Time display methods
Analog clocks
Analog clocks usually indicate time using angles. The most common clock face uses a fixed numbered dial or dials and moving hand or hands. It usually has a circular scale of 12 hours, which can also serve as a scale of 60 minutes, and 60 seconds if the clock has a second hand. Many other styles and designs have been used throughout the years, including dials divided into 6, 8, 10, and 24 hours. The only other widely used clock face today is the 24 hour analog dial, because of the use of 24 hour time in military organizations and timetables. The 10-hour clock was briefly popular during the French Revolution, when the metric system was applied to time measurement, and an Italian 6 hour clock was developed in the 18th century, presumably to save power (a clock or watch striking 24 times uses more power).
Another type of analog clock is the sundial, which tracks the sun continuously, registering the time by the shadow position of its gnomon. Sundials use some or part of the 24 hour analog dial. There also exist clocks which use a digital display despite having an analog mechanism—these are commonly referred to as flip clocks.
Alternative systems have been proposed. For example, the Twelv clock indicates the current hour using one of twelve colors, and indicates the minute by showing a proportion of a circular disk, similar to a moon phase.
Digital clocks
Digital clocks display a numeric representation of time. Two numeric display formats are commonly used on digital clocks:
- the 24-hour notation with hours ranging 00–23;
- the 12-hour notation with AM/PM indicator, with hours indicated as 12AM, followed by 1AM–11AM, followed by 12PM, followed by 1PM–11PM (a notation mostly used in the United States and Canada).
Most digital clocks use an LCD, LED, or VFD display; many other display technologies are used as well (cathode ray tubes, nixie tubes, etc.). After a reset, battery change or power failure, digital clocks without a backup battery or capacitor either start counting from 12:00, or stay at 12:00, often with blinking digits indicating that time needs to be set. Some newer clocks will actually reset themselves based on radio or Internet time servers that are tuned to national atomic clocks. Since the advent of digital clocks in the 1960s, the use of analogue clocks has declined significantly. |
From Wikipedia, the free encyclopedia
A clock is an instrument used to indicate, keep, and co-ordinate time. The word clock is derived ultimately (via Dutch, Northern French, and Medieval Latin) from the Celtic words clagan and clocca meaning "bell". A silent instrument missing such a mechanism has traditionally been known as a timepiece.[1] In general usage today a "clock" refers to any device for measuring and displaying the time. Watches and other timepieces that can be carried on one's person are often distinguished from clocks.[2]
The clock is one of the oldest human inventions, meeting the need to consistently measure intervals of time shorter than the natural units: the day; the lunar month; and the year. Devices operating on several different physical processes have been used over the millennia, culminating in the clocks of today.
How clocks work
The invention of the mechanical clock in the 13th century initiated a change in timekeeping methods from continuous processes, such as the motion of the gnomon's shadow on a sundial or the flow of liquid in a water clock, to repetitive oscillatory processes, like the swing of a pendulum or the vibration of a quartz crystal, which were more accurate.[32] All modern clocks use oscillation.
Although the methods they use vary, all oscillating clocks, mechanical and digital and atomic, work similarly and can be divided into analogous parts.[33][34][35] They consist of an object that repeats the same motion over and over again, an oscillator, with a precisely constant time interval between each repetition, or 'beat'. Attached to the oscillator is a controller device, which sustains the oscillator's motion by replacing the energy it loses to friction, and converts its oscillations into a series of pulses. The pulses are then added up in a chain of some type of counters to express the time in convenient units, usually seconds, minutes, hours, etc. Then finally some kind of indicator displays the result in a human-readable form.
[edit] Power source
This provides power to keep the clock going.
Since clocks must run continuously, there is often a small secondary power source to keep the clock going temporarily during interruptions in the main power. In old mechanical clocks, a maintaining power spring kept the clock turning while the mainspring was being wound. In quartz clocks that use AC power, a small backup battery is often included to keep the clock running if it is unplugged temporarily from the wall.
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