[ntp:questions] Building/cannabalizing a WWVB radioclock...

Pete Stephenson pete+usenet at heypete.com
Fri Aug 3 19:57:24 UTC 2007

In article <46B34E92.6020407 at comcast.net>,
 "Richard B. Gilbert" <rgilbert88 at comcast.net> wrote:

> WWVB radio circuits come in all sizes and shapes and may use anything 
> from the technology of the 1940s and 50s to "state of the art" solid 
> state devices.

Indeed. Perhaps that was a poor question for me to ask. :)

> Measure it!!!!

I'll see if I can head to the university's electronics shop today to see 
if I can borrow some of their equipment.

> D cells would probably die of old age before the active ingredients were 
> consumed.  I've been running a WWVB wall clock on the same pair of AA 
> batteries for 3-1/2 years now!

Lucky! This clock lasts about 6 months between changes of the batteries 
(standard Duracell batteries, no lithium or other fancy stuff).

> In large parts of the world, the WWVB signal is available only during 
> the hours of darkness! In some parts of the world the signal is not 
> available at all! The clock synchs up whenever it has a usable signal.

I'm in Arizona, a mere ~1,000km from the transmitter. WWVB signal is 
received on a constant basis by the University of Arizona time guy. My 
WWVB radio clock syncs during the daytime without any problems...there 
might be a few periods when it's not being received that I don't know 
about, as the clock only checks periodically.

> Do you have a useable signal 24x7x365?  If not, your clock is going to 
> be "free running" from 8-14 hours per day.

I believe so. It's presently 1:00pm local time and the sun is quite 
intense outside. I disconnected the batteries on the wall clock, 
reconnected them, and is indicating "full strength" on it's screen (the 
exact strength, I have no idea, I'm just going off of it's indicator) 
and has set itself to the proper time.

Pete Stephenson

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