"Geoffrey S. Mendelson" wrote:

It's a very simple system that is well documented. It's simple and slow
enough that anyone used to pulling apart data streams would be able to
decode it with a Z80 derived embedded processor, the ARM chips in dead iPods,
WiFi routers, etc would be "overkill".


I did it 20 years ago with a VIC-20, in Commodore Basic.


Here in Jerusalem, we don't receive the signals of WWVB, or the German
or UK equivalents here. Someone about 50 miles north and out of the
mountains has a clock that syncs, but he never told me which station it
uses (he may not know), or how often it syncs. This lead me to research
how one would do the opposite, devise a local transmitter with an
ethernet port on one end for NTP sync and a 60kHz transmitter to sync a
clock on the other.

I gave up due to lack of a suitable design for the transmitter, no receiver
and a lack of funds to obtain them. You probably could do it out of one
of the Linux based routers, and blink one of the status LED's to generate
the 50/60kHz signal.


You need a good antenna system to transmit on 50 or 60 KHz. Here is
a sat photo of the WWVB antenna farm:


http://maps.google.com/maps?hl=en&rls=com.microsoft:en-us&q=wwvb%20time%20signals%20ft%20collins&um=1&ie= UTF-8&sa=N&tab=wl


I know by now you must be thinking "why would anyone even think of such
a thing", but a discussion a few months ago about resurecting a Heathkit
Most Accurate Clock, got me going. I think I also read a posting that the
WWVB signals were being phased out.


They replaced all the transmitters and towers at WWVB a few years ago
to improve service. It now reaches Central Florida without a long wire
antenna & tuner. Why would they spend millions and take a couple years
to do the update if they were planning to shut it down?


--
You can't have a sense of humor, if you have no sense!