On Mon, 5 Nov 2012 04:38:51 +0000 (UTC), gregz
wrote:

micky wrote:
On Mon, 5 Nov 2012 03:36:36 +0000 (UTC), gregz
wrote:

micky wrote:
On Sun, 04 Nov 2012 20:00:33 -0600, Mark Lloyd
wrote:


There are so-called "atomic clocks" that do set themselves using a
signal from a satellite. I have a small one that I got very cheaply
at a hamfest, and

I don't know of any clocks except gps and such that use a satellite. Ground
beacons are sent from Colorado from NIST. Once, they used to broadcast from
near DC area. You usually can't pick up the signals during the day.

I guess you're right.
http://www.weatherconnection.com/pro...FUKd4Aod52gAHA
Only $14. Mine was more money origianally but very similar. It had
no box and I found brief instructions online, but they probably didn't
mention what you said.

" The atomic clock is updated daily to within one second of official
U.S. government time via radio signal from Fort Collins, Colorado, and
never needs resetting. The clock is accurate to within one second of
official U.S. government time.

This atomic alarm clock is also easily programmed to reflect which
available time zone you?re in (Pacific,Central, Eastern or Mountain)
and operates manually if traveling outside of the continental U.S. "

I also found a wris****ch
http://www.amazon.com/Casio-WV58A-1A...=clocks+atomic
under 30 dollars

I don't know if they have more than one cesium clock at the colarado
station. It used to be, the standard was averaged from banks of cesium beam
units near DC.separated from each other, along with one or more hydrogen
masers. The Current beacons may be synced by satellites.

Greg

I was reading they started using a new protocol modulation for newer
receivers. Some really old receivers may stop working. This is lower
frequency band, really low, but not as old as old stations that used to
transmit signals to subs. That was audio frequency. I have not listened o
shortwave wwvb in a long time. The time code could be read by the changing
of tones, really a low speed, but took less than a minute, then a 1 minute
sync signal.

Greg

Good to know. I seem unable to remember what the instructions say
about how it works. Right now it shows an image of an antenna, with
no radio waves. When it's getting the time it has waves and they
blink, it says, but I can't remember whether it blinked for hours and
hours or maybe it was just that the radio waves, the semi-circular
lines, were there for hours. Anyhow, I geuss mine is still working
on the new frequency, since it moved an hour Saturday night.