NavList:

   

Reply

Lu Abel wrote:
> WWV is indeed the "gold standard" but not always available reliably and 
cheaply, so alternatives such as time.gov or atomic clocks are reasonable 
parts of a navigator's arsenal.

But "not always available reliably and cheaply" would apply even more to
Internet time or a radio controlled clock, wouldn't it? I think a
navigator dependent on those time standards, without a shortwave
receiver, is living dangerously. If they disagree, how do you know which
one is wrong?

Shortwave reception isn't alway there, but if you can hear a time
station, you can trust it. There are no doubts about delay in the
network or within the device, e.g., the time display on a GPS receiver.

(In some applications the radio propagation time does matter, though. At
a place where I used to work, there was a rubidium clock which could be
checked or synchonized to ticks from a WWV receiver. The equipment
included a set of thumbwheels to input the distance to the station.)

For years I've made monthly rate checks on two of my clocks. For that I
rely on WWV via cell phone. The audio is 1/4 second late, a delay I
ignore because it's so consistent. Without a shortwave receiver I
wouldn't have that confidence.

There are several time broadcast stations scattered around the world:

http://search.yahoo.com/search?p=standard+time+frequency+stations

My receiver is an old Sony 2010 from the 1980s. Portables from China
nowadays do a decent job for well under $100 and would be good time
standards. A couple retailers who have been in business many years:

http://www.universal-radio.com/
http://www.grove-ent.com/

Some cheap receivers sold only through eBay or other outlets are said to
perform well for the money, if you don't mind Chinese instructions (or
none at all) and no warranty or support.

--

   

Reply