On Sat, 23 Jun 2012 08:40:54 +0000, FatallyFlawed
wrote:

(Private citizens tend not to own atomic clocks, they normally reside in
laboratories, and atomic clocks are powered by mains electricity, not
batteries, although there is likely to be an uninterruptable power
supply associated with them.)

Ummm... there are plenty of mere mortals that own cesium and rhubidium
standards that drive test equipment and sometimes clocks. The 1 pps
output from a GPS or cesium standard is quite useful for driving
clocks.
http://leapsecond.com
http://www.leapsecond.com/hpclocks/
Such atomic frequency standards are also available rather economically
on eBay. For example:
http://www.ebay.com/itm/280905645392 $86 for rubidium. (Note that
rubidium is not really a primary standard but is good enough for most
applications). Personally, I prefer a GPSDO (GPS diciplined
oscillator) which is more accurate and draws somewhat less power:
http://www.ebay.com/itm/170862678745 $158

As for requiring mains electricity, note that the power requirements
for the miniature rubidium and cesium fountains makes it possible to
operate from batteries. The unit above runs on 12V and burns 11 watts
after stabilization. Last time I checked, the GPS satellites, which
have internal Kernco cesium clocks, do not require a 20,000km
extension cord.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558