Lately, there’s been a big flap about the NIST time standard stations going off the air. Personally, I’d be kind of ticked off if this happened. I don’t use WWV and WWVH so much anymore, but I do have several clocks in my house that use the WWVB time signals. In fact, I recently purchased a couple of clock mechanisms from Klockit to convert even more of my clocks.
If you’re not familiar with the station, here’s how Wikipedia describes WWVB:
WWVB is a time signal radio station near Fort Collins, Colorado and is operated by the National Institute of Standards and Technology (NIST).[1] Most radio-controlled clocks in North America use WWVB’s transmissions to set the correct time. The 70 kW ERP signal transmitted from WWVB is a continuous 60 kHz carrier wave, the frequency of which is derived from a set of atomic clocks located at the transmitter site, yielding a frequency uncertainty of less than 1 part in 1012. A one-bit-per-second time code, which is based on the IRIG “H” time code format and derived from the same set of atomic clocks, is then modulated onto the carrier wave using pulse width modulation and amplitude-shift keying. A single complete frame of time code begins at the start of each minute, lasts one minute, and conveys the year, day of year, hour, minute, and other information as of the beginning of the minute. WWVB is co-located with WWV, a time signal station that broadcasts in both voice and time code on multiple short wave frequencies.
Here’s what a typical transmission looks like:
Anyway, if WWVB goes off the air, all of the clocks that use this signal will lose sync and have to be manually set, UNLESS you build one of the projects below:
μWWVB: A Tiny WWVB Station. This project uses an attiny44 microcontroller and a USGlobalSat EM-506 GPS module to simulate WWVB.
One Component Radio Clock Time Transmitter. This project uses an attiny45 microcontroller to simulate WWVB. As is, you set the time by changing some defines in the code. You’ll probably want to change that to get the time variables from a GPS source or an ntp source, but at least you’ll be able to generate the 60 kHz once you have that time information.
Both of these projects note that the transmitter range is not very great, so you’ll have to set the clocks very near the transmitter to get them to receive the signal. Even so, these look like great alternatives to keeping the clocks in operation should WWVB actually go off the air. With a little experimentation, you might even be able to extend the range of your transmitter and not only provide the time signal throughout your house but throughout your neighborhood as well.
Rory says
For me this would be a really bad deal, I work for a K-12 public school and we have over 200 classrooms and offices with clocks synced up with WWV. The cost for new Wifi clocks is about $120. So for the sake of saving the district a ton of money let’s hope that they stay on the air!
N6OIL
Peter L says
Are you certain they have 60-kHz receivers? The institute of higher ed for which I work has a radio master clock system, but it’s a GPS receiver that transmits time code on 72 MHz. Multiple buildings have the system. Google up Primex. WWVB’s potential demise won’t affect the system at all.
Now, if the current administration plans to turn GPS into a pay-per-view service, we got problems. :-D
Dan Marler says
See the petition at: https://petitions.whitehouse.gov/petition/maintain-funding-nist-stations-wwv-wwvh
Larry Beavers says
I purchased am MFJ 148 RC atomic clock. I set it according to the instructions, but I don’t see the WWVB signal. Is the transmitter on the air? I live in Apex, NC. Any tips to improve my reception?
Dan KB6NU says
Hi, Larry. If you haven’t already found it, go to the web page, Help with WWVB Radio Controlled Clocks. It has a bunch of tips on what to do if you’re not getting good reception.
Neil Murphy says
In my bedroom I have several “atomic clocks” none are in sync. 9.5, 4.5, 1 min fast. I would like them all to be in sync. Four “atomic” clocks beach with a different time is more than passing strange.
Dan KB6NU says
It doesn’t sound like they’re actually syncing with WWVB. One way to test that would be to put them all next to one another in a spot where you know you’re getting the signal. Then, if they all sync up, then you’d know they’re working correctly.
Mark Miller says
I wish there was an atomic clock with an external antenna connection, especially the MFJ 2625.
Dan KB6NU says
I agree. That would be very cool. I need to get back to that project.
Gary says
A resonant quarter wave antenna at 60 kHz is about 1200 meters long, so there’s not much chance you could plug anything useful into it.
Don Resor says
There are several projects on the internet for winding your wwvb antenna. At least one project is shown on YouTube here:
https://youtu.be/ySWpaAXiJCQ?si=H3AsPMtJp47cFT96