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November 20, 2005
Solar Atomic Clock
Solar power via built–in photovoltaic panels activated by sunlight, a lamp or wherever light's happening.
Clock with an internal antenna that picks up radio signals from the U.S. atomic clock.
Self–adjusts twice a year for daylight savings time.
Nice big (3"–high) numerals you can actually see.
Map shows your time zone.
12 or 24 hour display.
For walls, tabletops or desktops; built–in hanger and easel stand.
10" diameter.
$59.99 here.
November 20, 2005 at 09:01 AM | Permalink
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Comments
I have enjoyed several of these (non-solar) atomic-sync clocks and wrist watches over the past few years. This solar powered concept rocks!
The one weak point of these that I own is that you can still be SOL when the battery dies. I want one of these solar-powered versions for my wrist!
For those of you who have not tried these things, they totally change your perception of what care-free accurate time can be...the clocks are always right with zero effort.
The one issue for some is reception of the short wave radio signals (WWV and WWVH -- http://tf.nist.gov/timefreq/stations/wwv.html ) broadcast by the National Institute of Standards and Technology in Boulder, Colorado (your tax dollars at work).
Reception is good in LA and SF (and all of the states east of the rockies). Some trouble when your house is located on the "away side" of tall hills/mountains (radio shadow) relative to the transmitter in boulder...but even there, short waves work OK in the middle of most nights...so the clocks usually update by dawn...
Here's how it works:
http://tf.nist.gov/timefreq/stations/overview.html
and
http://tf.nist.gov/timefreq/stations/wwvtimecode.htm
Here's some info on ataomic clocks:
http://hyperphysics.phy-astr.gsu.edu/hbase/acloc.html
"The frequency of the national atomic clock is based on the frequency of a transition in the Cs-133 atom:
1 second = 9,192,631,770 cycles of the standard Cs-133 transition. For comparision, a quartz watch is based on ~40,000 oscillations per second, a tuning fork watch (accutron) ~1000, and a fine ticking watch ~5 cycles per second. More cycles = greater accuracy.
The Cs-133 transition rate is in the microwave region of the electromagnetic spectrum. Cesium clocks have demonstrated stability to 1 part in 10^13, or one second in 300,000 years.
Set your watch by it via phone (303) 499-7111.
More cool info on atomic clocks here:
http://www.ewh.ieee.org/reg/7/millennium/atomic_clock/atomic_seeds.html
Posted by: sb | Nov 21, 2005 11:54:33 AM
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