Alan Kruse wrote: > Hi, > > I was referring to a list of hardware or software that will provide time. > > Al > > > On 1/16/06, Rob Kimberley <[EMAIL PROTECTED]> wrote: > >>Hi Al, >> >>When you say "time synchronisation hardware and Software" do you mean NTP >>compatible or any hardware that will provide time. If the latter, then the >>list is a very long one indeed. Not sure that such a list exists, but >>interested to see what others come back with. >> >>Kind Regards
A clock consists of a frequency standard plus a counter. Accordingly, a list of "hardware" that provides time would include: A. Mechanical wrist watches and mechanical clocks. For these, the frequency standard might be a pendulum, and the the counter might be an arrangement of gears to count seconds, minutes, houts, etc., and display them on mechanical dials for the user to observe. B. Electrically powered wristwatches and clocks that include tuning forks as their frequency standard. C. Electrically powered wristwatches and clocks that include crystal oscillators as their frequency standards. Most retail clocks and wristwatches fall into this category. D. Wristwatches and clocks that include crystal oscillators that are "synchronized" from time to time with radio receivers. These include, for example: D.1. "Atomic Time" and other brands of wristwatches and clocks that synchronize their dials (counters) against the 60 kHz LF signal from WWVB near Ft. Collins, Colorado. D.2. Similar products that synchronize their dials against other LF signals from other LF (low frequency) or MF (medium frequency) time signal stations such as MSF (Rughy, United Kingdom, 60 kHz); TDF (Allouis, France, 162 kHz); HBG (Prangins, Switzerland, 75 kHz); etc. D.3. Similar products with HF radio receivers for such time and frequency stations as WWV (Colorado, USA: 2.5 MHz, 5.0 MHz, 10.0 MHz, 15.0 MHz, 20.0 MHz), WWVH (Hawaii, USA: 5.0 MHz, 10.0 MHz, 15.0 MHz), CHU (Ontario, Canada: 3330 kHz, 7335 kHz, 14670 kHz), BPM (Shaanxi, China: 2.5 MHz, 5.0 MHz, 10.0 MHz, 15.0 MHz), etc. D.4. Similar products that both "synchronize" their counters and "syntonize" their frequency references against standard time and frequency broadcasts. D.5 Similar products that either "synchronize" their counters (or both "synchronize" their counters and "syntonize" their frequency standards) against signals received from GPS satellites. Almost any GPS receiver will display time of day. (Many will not, however, display it in a "timely" manner!) GPS receivers that are to be used for precise timing purposes should provide a 1 Hz (1 pulse per second) output. Some of the better ones will provide 5 Hz or 10 Hz outputs, if they provide fixes 5 or 10 times per second. As Rob Kimberly said, a list of hardware timing devices could be rather lengthy! It would help if you could be more specific, and perhaps rule out such devices as mechanical clocks and chronometers. -- James Maynard Salem, Oregon, USA _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
