Rack Clock
Chosen as GPS or MSF Timing Reference for NTP server
All PCs and networking devices use clocks to maintain an internal time of the system. These clocks called Real Time Clock chips (RTC) provides time and date. They are battery backed so that even during power outages, can keep time. However, personal computers are not designed to be perfect watch – the design has been optimized for mass production and low cost, rather than maintaining a precise time.
These internal clocks are prone to drift and, although the application of many, this is can be very adequate for some applications, but the machines on a network that comes at different speeds, they become out of sync with each other and problems can arise, especially with time sensitive operations.
The NTP (Network Time Protocol) uses a single reference time to synchronize all machines on the network of a time reference. This time reference can be relative (internal clock time on a computer or a watch perhaps) or absolute as UTC (Coordinated Universal Time) clock source like an atomic clock is accurate as is humanly possible.
For some applications, a source on time is sufficient, however, in many environments, such as airlines and the marketplace is essential for the time to be absolute. Imagine buying an airline seat only to be told at the airport that the ticket was sold twice because it was acquired through on a computer that had a slower clock!
Atomic clocks are the absolute best time-keeping devices. Working on the principle that the atom Cesium-133, has an exact number of cycles of radiation every second (9192631770). This demonstrated accurately the International System of Units (SI) has defined the second as the duration of 9192631770 cycles of the radiation of cesium 133 and development of UTC (Coordinated Universal Time) now means that the computer can be synchronized across the workld the same time.
However, atomic clocks are extremely expensive and are generally only to be found in large scale physics laboratories. However, NTP servers can synchronized networks of an atomic clock by using the global positioning system (GPS) network or specialist radio transmissions (MTF in the United Kingdom). It should be noted that Microsoft and others strongly suggest that external based timing should be used rather than Internet based, as these can not be authenticated. Server Specialist NTP is available that can synchronize the time on the networks using the MSF (or equivalent) or GPS time server signal.
GPS is the ideal time and frequency source because it can provide highly accurate time anywhere in the world using relatively low cost components. Each GPS satellite transmits two frequencies for use L2 Military and L1 for use by civilians transmitted at 1575 MHz, low-cost GPS antennas and receivers are now widely available.
The radio signal transmitted by satellite can pass through the windows, but can be blocked by buildings so the ideal location for a GPS antenna is on a roof with a good view of the sky. The satellites are can receive the best signal. However, roof-mounted antennas may be prone to lighting strikes or other voltage surges so a suppressor is highly recommended be installed on the GPS cable line.
The cable between the antenna and GPS receiver is also critical. The maximum distance a cable can be run is usually only 20-30 meters, but a High Quality coax cable combined with a GPS amplifier placed in line to increase the gain of the antenna can allow more than 100 Meters cable runs.
There are also a number of national terms and the radio frequency that can be used to synchronize an NTP server. Great Britain the signal (called MSF) is broadcast by the National Physics Laboratory in Cumbria which serves as a reference point of the UK national time, there are similar systems in Colorado, USA (WWVB) and Frankfurt, Germany (DCF-77).
A radio based NTP server usually consists of a rack-mountable server time, and an antenna, consisting of a iron bar inside a plastic box, which receives radio broadcasting time and frequency. It must always be mounted horizontally at right angles to the transmission optimum signal strength. Data is sent in pulses, 60 of a second. These signals provides UTC time to an accuracy of 100 microseconds, however, the radio signal has a range finished and is vulnerable to interference.
Both a GPS NTP server and time server MSF can provide a convenient and efficient way to synchronize accurately networks of computers with NTP.
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Premium Wood Day by Day Wall Clock $8.04 UPC: 844296056828The Day-by-Day wall clock is a perfect gift for retirees and others who can afford to measure time in days rather than hours! This distinctive time keeping device doesn’t tell you what time of day it is, it tells you what day it is. Its legible dial is divided into seven equal parts for each day of the week so that any question of what day it is can be quickly and easily answered…. |
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Tiki Bar Chrome Finished Neon Clock by Neonetics (red) (15H x 15W x 3D) Time will fly with this Tiki Bar Chrome Finished Red Neon Clock. Glass face quartz movement. Great for the gameroom or bar. Hand blown neon. Great 3 tiered art deco rim. IMPORTANT NOTE TO CUSTOMERS: the only neon in the clock is the circle AROUND the clock. THE TIKI GRAPHIC ON THE FACE IS A PICTURE OF A SIGN, NOT ACTUAL NEON. Neon lasts upwards of 10 years. mixed media neon plastic and glass… |
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Dallas Cowboys Round Clock $18.24 Officially licensed wall clock. Great for any room. High quality quartz movement with a sweep second hand. Molded plastic construction with built in hanger. Measures 12.75″ in diameter. Made in USA…. |
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Time Card/Ticket Message Rack, 12/36/54 Pocket, Gray (MMF27018JTRGY) Category: Time Clocks and Cards $45.30 Item #: MMF27018JTRGY. Sturdy steel rack accommodates many types of materials such as job tickets and time cards. Use for a single or multiple installation. Offers slotted cut-outs on the back for wall mounting. Pockets and frames are interlocked with pocket dividers permanently positioned. Use full width or divided into smaller pockets by inserting divider rods which are provided. Minimum 30 perc… |
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Bar and Game Room It’s 5 O’Clock Somewhere Neon Sign 55-o’clock-somewhere-neon-sign,75,,,,, Bar and Game Room collection is the perfect addition to any game room, bar, or restaurant. The poster comes ready to hang and plugs into regular electrical outlets. It has a fun lighting combination that includes neon lights as well as LED accents throughout. Give your walls a bright new look! Features: -”It’s 5 o’clock somewhere” neon sign. -Bar and Game … |
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Family: the web series – Season 1 $20.00 Set in Seattle, this polyamory themed series follows the lives of threesome (triad) Gemma, Ben and Stuart, as they navigate their own polyamorous lives in the monogamous world around them…. |
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TOILET SAFETY RAIL, Bath safety grip also available! Sturdy arms and no-slip feet for added safety. Easily fits around toilet. Provides additional assistance to those who need support sitting down or getting up from a toilet seat…. |
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Rack’em 9 Ball 14-Inch Neon Wall Clock $68.73 14-inch rackem clock. Appeals nicely at home or for a business. It is a great piece for get-togethers during ballgames recreational activities and appeals nicely in gamerooms. features include: high polished chrome finish molded resin housing full color rackem 9 ball logo yellow neon ring on outer edge battery operated quartz clock mechanism 110 volt power supply for power to the neon lights inclu… |
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Rack’em 8 Ball 14-Inch Neon Wall Clock $68.73 14-inch rackem clock. Appeals nicely at home or for a business. It is a great piece for get-togethers during ballgames recreational activities and appeals nicely in gamerooms. features include: high polished chrome finish molded resin housing full color rackem 8 ball logo yellow neon ring on outer edge battery operated quartz clock mechanism 110 volt power supply for power to the neon lights inclu… |
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Phonic Firefly 808 Universal Studio Recording Preamp with 192 kHz USB 2.0 + FireWire Interface $450.00 The Phonic Firefly 808 Universal rack-mountable preamplified unit with USB and FireWire interface is an easy-to-use, high-quality recording interface for songwriters to record guitars, keyboards, vocals, and more to the computer. Featured are 8 analog (XLR and 1/4″) inputs and 8 analog (1/4″) outputs, as well as S/PDIF, AES/EBU, MIDI and ADAT inputs and outputs — all of which are streamed to… |
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The Clock $41.86 The Clock |
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Clock $12.99 CLOCK, THE (DVD MOVIE) |
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Yonder Is The Clock $10.99 Yonder Is The Clock |
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Dandelion Clock $11.99 Dandelion Clock |
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Pass The Clock $29.99 Pass The Clock |
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Stop That Clock $14.99 Stop That Clock |
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Doomsday Clock $15.99 Doomsday Clock |
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Cube Clock $19.75 Cube Clock |
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Kid Clock $14.99 Kid Clock |
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Ninja Clock $19.99 Ninja Clock |
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Potato Clock $17.95 Potato Clock |
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The Death Clock $12.76 The Death Clock |
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Cuckoo Clock $16.95 Cuckoo Clock |
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A Clock With No Hands $14.09 A Clock With No Hands |
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The Autobiography of a Clock $23.46 The Autobiography of a Clock |
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The Clock of Peaceville $23.6 The Clock of Peaceville |
