h a l f b a k e r yTempus fudge-it.
add, search, annotate, link, view, overview, recent, by name, best, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Please log in.
Before you can vote, you need to register.
Please log in or create an account.
|
Henceforth all clocks shall be fitted with a receiver which adjusts the time displayed by that clock to match exactly the time signal transmitted by a satellite in geosynchronous orbit. There will be a separate row of satellites for each time zone on the planet (including Nepal, which insists on setting
its clocks 15 minutes ahead of India out of spite). Each satellite will only transmit to a footprint analogous to the area it is to service so it will not be possible to choose between two different times if you are close to a time zone border. Daylight saving adjustments will occur automatically. Time delay in transmission is accounted for by the transmission of minutely different signals to each area of 10m x 10m on the Earth's surface.
It will also transmit the signal using ULF radio so submariners can use the system. If you work underground or at some point in the day go underground your watch will adjust to perfect time as soon as you are back in an area where transmission reaches.
VCRs, microwaves and other electric clocks which always seem to slightly out of sync or very difficult to set will be brought into line. Unfortunately the talking clock guy will be out of a job... too bad, learn to move with the times (*time* now)
This idea was inspired by the Uncertainty Timepiece.
The Uncertainty Timepiece
http://www.halfbake...rtainty_20Timepiece
If it doesn't speak for itself, you'd best go check it out [-alx, Jun 17 2001, last modified Oct 05 2004]
Radio Atomic Clock
http://www.weatherc...om/atomicclock.html
A clock that syncs to atomic time... [goff, Jun 17 2001, last modified Oct 05 2004]
Self Adjusting Wristwatches
http://www.halfbake...djusting_20accuracy
Another version of this warm and crusty idea.. [goff, Jun 17 2001, last modified Oct 05 2004]
[link]
|
| |
But this device as described above will eliminate almost all temporal uncertainty. I cannot allow this travesty to stand, sir. |
|
| |
I'm not really concerned with how sharp satellite coverage is at the moment. There will be a way to collimate the transmitted beam to allow this to work. It's just not something the techies have bothered to concentrate their energies upon to this point. |
|
| |
As for why Peter; until this thing is baked there is no way to be sure what the time really is, it's just so haphazard and arbitrary. No more uncertainty with this little sucker... "Sonny, you were 14.62548276485 seconds late for work this morning." |
|
| |
Not available via satellite, but still very baked. Have given just the first link I found for a U.S version which reads a radio signal from an atomic clock. I know that they are also available for most of the developed world. Don't know how far the radio signal reaches though so don't know about inaccessable places like antarctica, but wouldn't take much to extend it. Sorry Bubbs. |
|
| |
Also marked as baked under better wristwatches - see link |
|
| |
Doesn't need to be done by a satellite coverage shadow, you just have to have a two-way communication between the clock and the Royal Observatory at Greenwich. Time is all relative, as we know, and due to the pre-eminence of Mr Harrison, it is all relative to a leafy part of East London, UK. Your clock (or watch) talks to a satellite to find out its exact position (and as we know, GPS can be accurate to at least a few metres). It then asks Greenwich what is the time, and Greenwich works out which time zone the watch is in, and informs it accordingly.
Alternatively, Time Zones could be abolished, and your watch could always display GMT+((<yourlongitude>-180)*4). Longitude in degrees - you only get an accuracy of 4 minutes, and the output is in minutes i.e. at 90 west of Greenwich it's minus 360 minutes from GMT, which is six hours. Just don't live west of where you've got to be at 9am. |
|
| |
PeterSealy, you're no fun. wouldn't it be great to live half an hour travelling time away from work, and leave when it said 8.30 on your watch, and when you get there it's like it took you half the time. Alternatively the people that lived to the west all get there late. (Problem for you in NYC I suppose, you'd have to live in the sea to be early.) |
|
| |
Because GPS works by comparing the time radio signals take to get to you from different satellites, it can be used as a time source directly, and often is (you can buy GPS receiver cards for computers which don't bother to compute their position, they just tell you the time to high accuracy.) Every GPS satellite has an atomic clock onboard and they're all carefully coordinated to TAI (and to UTC, GMT, etc.) |
|
| |
Of course, the WWV signal is good enough for most of us (we don't care if we're a quarter-second off) and is used in more affordable products like those that goff has linked to. |
|
| |
I was loath to mention the use of GPS technology for fear of derision by the other members of the Happy Cuddle Club... it appears I need not have bothered. I'd still like to have a watch which was dead accurate for every place on the planet. |
|
| |
I sincerely doubt a ground 2-way system would work in the middle of the Simpson Desert , which is a bloody great patch of nothing in the middle of Australia. For this reason I postulated that it be delivered by satellite. |
|
| |
Fly across the Pacific at night. It's a little difficult to tell during those 15 hours over water. |
|
| |
If you want to send an email to someone en route it may be helpful to know when you sent it, particularly if timing is important. Time does not stop once you're inside an aircraft. |
|
| |
Why does it particularly matter what (local) time it is during a flight across the Pacific? If you're planning to meet someone at your destination, you'll be interested in their local time, not yours. |
|
| |
[egnor], I do believe that may be derision dribbling down your tie as you drool with delight over my acknowledgement. |
|
| |
I don't have time for all this! No, wait...I do. Sterling, sir! |
|
| |
The Global Positioning System (GPS) is already the "gold standard" for accurate time distribution. And as the name implies, it is globally available. Even a ring of geostationary satellites cannot provide global coverage (there's none near the poles). |
|
| |
The only hard part of your proposal is the automatic correction for time zone. But time zone boundaries are political and rather arbitrary. So the only way to correct for them is to look up your position on a timezone map. Again, as the name implies, GPS gives you your position. So you already have everything you need but the timezone map. Easy! |
|
| |
If you're in the continental US, and you want something that works well inside a house (no outside antenna), and you are only driving a clock display (so microsecond accuracy isn't important) there are already clocks on the market that synchronize themselves to the 60kHz transmissions of WWVB in Ft Collins, CO. I bought two different models of these clocks last weekend at Costco for only $20 each. One large for hanging on the wall, and one small for the nightstand and for travel. But you have to set the timezone manually. |
|
| |
By the way, WWVB indicates when US daylight savings time is in effect, while GPS (being a global system) does not. The rules vary from country to country, so they could be applied in the same way as timezones, with a map. |
|
| |