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Playing With Atomic Clocks At Home
Wired is running a profile of the Time Nuts, a small group of people who buy surplus precision time equipment — cesium clocks for example — on eBay and keep really accurate time, because they can. The article quotes Tom Van Baak, who has outfitted a time lab superior to those of many small countries: "If you have one clock... you are peaceful and have no worries. If you have two clocks... you start asking, 'What time is it, really?'"
...Some people have too much time on their hands.
=Smidge=
I like to be REALLY just on time for my meetings...
Every experiment which ends in a big bang is a good experiment.
Real men just run ntpd and let the whole world keep time for them.
Hammer time.
...who can have two or more clocks and not constantly ask myself "what time is it?... really?"
Anyone can make the world keep time for them. Only real men can make the sun keep it for them.
I think we can keep recursing like this until someone returns 1
If you really, really know what time it is. You will find yourself quite lost. Darn that Heisenberg!
Break the sound barrier - bring the noise.
I always said it was fun to throw a clock out a high window so you could see time fly!
One must much more careful with these new atomic clocks. After time flies, they explode and destroy whole cities!
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
This is really the first post; your clocks just don't agree with mine.
"Quoting famous computer scientists out of context is the root of all evil (or at least most of it) in programming." - K
Radio controlled clocks are sometimes called atomic clocks because their underlying time resides in a Colorado atomic clock.
These clocks give accuracy within a second as does the ntpd daemon on Unix computers.
The world seems in balance when you set 3 radio controlled clocks in front of your computer,
then watch all four with the same hour, the same minute, count the same seconds.
You shouldn't tell your clock the time -- your clock should tell you the time,
which radio controlled clocks and computers running ntp do tell.
Frustrated by clocks throughout my home with different times,
advanced by my wife to advance me, one clock advanced by 3 hours;
I got 7 radio controlled clocks which she cannot set because they set themselves.
Additionally, they give the day of week (Wednesday) and the date (December 11).
I first saw a radio controlled clock in 1992 while in Germany -- a $200 clock made by Jungans.
Several internet companies which mainly sell weather equipment also sell radio controlled clocks.
I purchased 7 of these made by Lacrosse, which can have a big LCD and can cost as little as $10 (US).
Your missing out if you only skimmed the article. Make sure you find this gem:
When the family returned to the suburbs two days later, the cesium clocks were off by the precise amount relativity predicted. He and his family had lived just a little more life than the neighbors.
An amazing PROOF that time is actually affected by gravity. We still know so little (ahem) relatively about time in physics, that seeing evidence of it being manipulated in this manner is awesome. will there be giant contained gravity wells in ambulances to slow time while patients are rushed to the hospital? Will I be slowing down time so I can get First Post AND spell check? The possibilities are endless!
Nothing great was ever achieved without enthusiasm
I would also venture to guess that he has no girlfriend.
SJW: Someone who has run out of real oppression, and has to fake it.
It's a hobby. Some people like to ride, say, horses for a hobby. Not terribly useful now everyone has cars. What's the use? The use is that someone enjoys doing it. Like the horse rider, the time keeping hobbyist enjoys tinkering with highly accurate time pieces.
If you have to question why people have hobbies you don't find interesting, you're amazingly lacking in imagination.
Oolite: Elite-like game. For Mac, Linux and Windows
NTPD isn't good enough for me -- bad weather on the Internet has caused my server to loose synchronization one too many times, which can be mighty irritating when comparing your log files with those of other systems. On the other hand, acquiring an atomic clock seems a bit over the top to me. So, I figured a good compromise solution would be to connect a GPS receiver to my serial port and synchronize NTPD to that. I've ordered a Garmin GPS 18 OEM LVC that I will receive later this month (hopefully). According to these instructions it's not that difficult to set up, while the result is microsecond precision on Linux 2.6 and nanosecond precision on BSD -- good enough for me. All you need to do is to make sure that your GPS device has a reasonable view of the sky.
Sure, he's got all those fancy clocks in his "Time Lab", but they only go forward!
- RG>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
Isn't it obvious? It wasn't relativity, the family lived an extra 22 milliseconds because they drove up a mountain and were closer to God. That's the only logical solution, I can't see this "gravity" you speak of. Every time someone has a problem with time physicists think they can solve it just by throwing a few nanoseconds at it. Ridiculous...
They got the saying all wrong. It goes "A man who wears one watch always knows what time it is; a man who wears two watches is never sure."
Those who fail to understand communication protocols, are doomed to repeat them over port 80.
For extra fun, tell him that they are all twenty minutes slow, making him late for school.
Despite the amount of confusing clocks you might have, a benevolent dictator of time becomes handy: Temps Atomique International (french) abbreviated: TAI. For us mere mortals who use time for civil needs, another timescale is dissiminated, Coordinated Universal Time (UTC). UTC is derived from TAI, but synchronized using leap seconds to UT1, which is based on actual rotations of the earth with respect to the mean sun.
International Atomic Time (TAI, from the French name ) is a high-precision atomic time standard that tracks proper time on Earth's geoid. It is the principal realisation of Terrestrial Time. As of 2007 TAI is exactly 33 seconds ahead of UTC: 10 seconds' initial difference at the start of 1972, plus 23 leap seconds in UTC since 1972. TAI in this form was synchronised with Universal Time at the beginning of 1958, and the two have drifted apart ever since.
Accurate time is very important for computer systems/networks. The best way to keep track of time is to install a local timeserver which synchronizes against a reliable public timeserver like pool.ntp.org. The local time server can be used to synchronize other computers you might have.
OK, as much fun as it would be to have my own stratum-1 NTP server, how do you (read: some ordinary joe, not a university researcher) synchronize these things to TAI in the first place?
...lunch-time doubly so.'
Ford Prefect. Which is very apt, because today is Mos Def's birthday.
Shiny. Let's be bad guys...
What's the fascination with uber-accuracy at home?
They are calling these "clocks" only because that is what the typical reader understands. A better term is "frequency standard". There are many uses for a stable frequency, the most common one is running a microwave transmitter. This is the major source of the surplus devices too, from cell towers. As the phone companies modernize equipment these "clocks" find their way to eBay and then into people's houses.