Annotated edit history of
TimeSources version 3, including all changes.
View license author blame.
| Rev |
Author |
# |
Line |
| 1 |
AristotlePagaltzis |
1 |
!!! Sources of Time in New Zealand |
| |
|
2 |
|
| 3 |
SamBailey |
3 |
!! [Network Time Protocol (NTP)|NTP] |
| 1 |
AristotlePagaltzis |
4 |
|
| |
|
5 |
See [NTPServers]. |
| |
|
6 |
|
| |
|
7 |
!! Global Navigation Satellite Systems (GNSS) |
| |
|
8 |
|
| |
|
9 |
[GPS] time signals have an accuracy of ±10ns, making them the best option for most applications. The planned establishment of Galileo by the European Union and Compass by China will provide additional sources of time for compatible receivers. |
| |
|
10 |
|
| |
|
11 |
It's possible to [sync a computer directly to the Pulse Per Second (PPS) output of a suitable GPS device|http://gpsppssync.sourceforge.net/] using a serial or parallel port. For better accuracy, there are [PCI] cards available with PPS inputs and/or built in [GPS] receivers. There are a variety of dedicated [NTP] servers available, some with internal oscillators that can maintain a stable clock if the satellite signal is lost. |
| |
|
12 |
|
| |
|
13 |
If you require better accuracy than [GPS] can provide, OmniSTAR provides [GPS] and GLONASS correction data via a worldwide network of geostationary satellites and reference stations. |
| |
|
14 |
|
| |
|
15 |
!! SW Radio |
| |
|
16 |
|
| 2 |
AristotlePagaltzis |
17 |
It might be possible to receive [the 5, 10 and 15 MHz signals broadcast from NIST's WWVH facility in Hawaii|http://www.nist.gov/pml/div688/grp40/wwv_format.cfm]. WWVH continuously broadcasts a time code on a 100-Hz subcarrier. The time code presents UTC(NIST) information in [BCD] at a rate of 1 pulse per second. (See [broadcast format|WikiPedia:WWV_(radio_station)#Broadcast_format].) |
| 1 |
AristotlePagaltzis |
18 |
|
| |
|
19 |
!! FM Radio |
| |
|
20 |
|
| |
|
21 |
Radio New Zealand broadcasts UTC(MSL) time signals on many of it's stations every hour. They consist of six “pips” of 1000 Hz tone, at one second intervals, the beginning of each pip marking the exact second. When a pip marks the exact hour, its length is doubled. When a leap second is inserted seven pips are broadcast. |
| |
|
22 |
|
| |
|
23 |
!! Digital TV |
| |
|
24 |
|
| |
|
25 |
Freeview transmits local time information using DVB-T at least once every 15 seconds with an accuracy of ±2s. |
