Radio Station WWV | Hacker News Reader

Radio Station WWV

nist.gov

60 pointsartursapek50 comments

This, along with the WWVB station[0] that makes most of your "atomic" wall clocks work, is an underappreciated national (and international) resource that was almost shut down recently[1] due to budget cuts.

I'm not going to link directly to any of them because of the Hacker News hug of death, but do a web search for "websdr", find a US based or nearby location, and try tuning to either 5000 kHz, 10000 kHz, or 15000 kHz (depending on the time of day - lower frequencies are usually better at night), AM mode, to listen in.

[0] https://en.wikipedia.org/wiki/WWVB

[1] https://cqnewsroom.blogspot.com/2019/03/wwv-funding-restored...

Yeah, I dunno, putting a hedge-fund manager at the head of the Commerce Department that is in charge of the national standards labs...

One of those times when Congress should have had the courage to say, "No, Donny," but didn't.

I prefer someone with knowledge of finance being the head of a department very heavily involved in finance. Whether or not the particular person was the right guy is a determination I personally wouldn't make on his job alone.

There's a vast gulf of knowledge in between a hedge funder famous for vulture capital restructuring and someone capable of effectively and prudently running a government department.

It's like saying "I prefer someone technical managing my mainframe" after appointing a web designer to the role.

I would literally have more faith in someone who had served as treasurer at a large church running the Commerce Department compared to someone like 83-year old Wilbur Ross.

Or just buy a shortwave radio! They are still made, and a high quality shortwave antenna for receiving purposes is simply a length of wire, as long as possible, and as high as possible.

The shortwave band (also known as “HF” radio) is a fascinating introduction to the subject, and while it is no longer full of long-range commercial radio stations, the propagation characteristics of the band mean it is still useful for things like WWV and amateur radio communication.

If you live on the west coast, you can enjoy the pleasure of receiving both WWV (broadcast from Colorado) and WWVH (broadcast from Hawaii) at the same time, on the same frequency. Their voice announcements are intentionally offset so that they never overlap.

If you have one of the popular RTL-SDR's you may be able to pick up the HF bands by enabling the direct sampling mode (allows tuning between 500kHz - 28.8MHz).

https://www.rtl-sdr.com/rtl-sdr-blog-v-3-dongles-user-guide/

NIST was the one that proposed closing the WWVs as a means of getting attention (and their full ask) during the 2019 budget negotiations. The good ol "Washington Monument" strategy.

Hard to justify the utility of the WWVB station with the coexistence of 4 going on 5 independent GPS systems along with telephone/cellular and internet systems. Pull is preferable over push given the use is not to be a canary; jamming a single time source is not strategically relevant. If it was there would be security at the station, but as is in a residential area some one could walk up with a power tool and take it down.

One system is land based. The others are space based.

The world needs redundancy especially in the presence of solar flares that can knock out satellites.

> Hard to justify the utility of the WWVB station with the coexistence of 4 going on 5 independent GPS systems.

All those GNSS systems use the same frequencies that can easily be jammed:

* https://gssc.esa.int/navipedia/index.php/GNSS_signal

Even the US government themselves recognizes the importance of resiliency:

* https://insidegnss.com/dot-report-on-backup-pnt-technologies...

* https://www.transportation.gov/briefing-room/us-dot-releases...

Shutting it down would have made every single existing radio controlled clock e-waste, overnight. And not just random wristwatches and wall clocks, but school and industrial clocks. None of these will work with GNSS signals.

That's the point, to stop creating this e-waste. If those applications are critical, then the owners should never have bought vulnerable radio controlled clocks in the first place.

Your assertion doesn’t even make sense. The hardware (wall clocks) could be older than gps. And gps is not only more expensive to receive, it’s harder too (most of those clocks would be indoors).

And the wwv signal is far more robust than gps.

Radio clocks are vulnerable to signal loss and spoofing regardless if it is GPS, cellular, or HF. If the time accuracy is critical, then the time signal should be delivered by wire to device, especially indoors. Wall clocks should have a manual way to set the clocks given there has never been a guarantee to receive the WWV signal. If expense is the concern along with wireless capability, then an integrated 2.4GHz SoC could be used that costs pennies; https://www.beaglesoft.com/radsynreceiver.htm appears to cost hundreds.

Well of course you can’t design against every eventuality, just the most likely.

> If expense is the concern, ... costs pennies.

I don’t suppose you’ve ever worked on a product where a couple of pennies would sink the BOM. Not to mention antenna design and cost.

You may have arrived at this view due to lack of visibility on what WWV does.

WWV also provides: - stable reference frequencies for maritime and aviation radio and also for terrestrial radio tuning - space weather alerting for radio system operators - GPS system status updates for maritime and aviation - High accuracy intervals and UT1 corrections (which used in conjunction with GPS for highly accurate position measurements)

Despite sounding like some legacy thing, this is a highly active system used by a lot of folks. I built a stratum 1 NTP system for power grid a few years ago using EndRun high accuracy appliances and we used GPS and WWV as the sources.

https://tf.nist.gov/stations/iform.html

The reference frequency part is very important. There is a lot of test gear that relies on a 10 MHz signal for calibration.

Very accurate reference frequencies can be obtained by syncing an oscillator to a GPS receiver clock output (0). I'm however all for maintaining traditional shortwave (not just time and frequency) radio stations on, for being much easier to receive and harder to control by governments.

0: https://en.wikipedia.org/wiki/GPS_disciplined_oscillator

Yes, we could have a partial backup to a 1.7 Billion/Year program for less than 0.007 Billion per year, but no.. that's too expensive?

Any program cost has to be evaluated with respect to its benefits, even if it insignificant in face of most government spending. The question is if the cost to have this backup to synchronize time over radio to increase the reliability within Broadcast Outage limits of WWV is less than the costs that would occur due to time drift with all of the existing systems being unavailable given their expected reliability.

This reminds me of the first true atomic wristwatch[1].

[1] http://www.leapsecond.com/pages/atomic-bill/

A much lengthier and more comprehensive paper if you are interested in WWV, WWVH, WWVB and their history and technology:

https://tf.nist.gov/general/pdf/1969.pdf (2005)

Pages 5-6 have an interesting note on the WWV announcers. The current voice (unless it's changed recently) is the late Lee Rodgers of San Francisco radio fame.

WWV and WWVH will be sending a new test signal on minute 8 for WWV and minute 48 for WWVH.

https://www.youtube.com/watch?v=O3Q7L0TNGtk

The test signal .wav file is available here:

https://zenodo.org/record/5602094

Whoa! I predict that the 8-second sequence of up & down chirps (YT vid 10:28) will not be popular (primum non nocere) - unless the level is a lot lower!

One fun thing was, when the added a leap second, they added it at midnight Greenwich time, which would be early evening in the US. You could count the ticks and hear the extra second happen.

How did that work? You just had to count and hear 60 instead of 59 ticks between the minutes?

Yes (with one solid tone for the first second of the minute, IIRC).

see also, the original in WWVB receiving wristwatches:

https://en.wikipedia.org/wiki/Casio_Wave_Ceptor

https://www.google.com/search?client=firefox-b-1-d&q=casio+w...

the older models of waveceptor, if you've had one in a box or stored for a long time, need to be left by a window overnight until they successfully synchronize.

There's plenty of nixie tube clock kits out there, but how many receive WWV (or WWVB) for accuracy? This one is one of the best, it shows the acquisition and decoding of the WWVB signal and the setting of the clock. I promised myself to build it someday.

https://www.youtube.com/watch?v=smUwbzA9SEo&t=844s

The WWV phone service that reads the time and a ticking noise is great for very basic testing of VoIP outbound call flow (don't abuse it!)

https://www.nist.gov/time-distribution/radio-station-wwv/tel...

My dad was a HAM radio operator, and as a kid I used to tune in WWV on some of his radios. There was just something wonderfully magical about that -tock- -tock- -tock- sound and the voice. It was at its best when the signal was kind of weak and hard to tune in perfectly.

I liked it enough to make this a couple of years ago, when there was an growing risk of WWV being shut down: https://wwv.mcodes.org. Alas it won’t give you your weak reception vibe, though there have been requests for that!

"When the signal was kind of weak" ... yeah it was something magical. And (almost) always there.

Morever, the known-constant signal is a useful way to check propagation conditions at those different frequencies, and to those different locations.

Easier for me to pick up CHU:

https://en.wikipedia.org/wiki/CHU_(radio_station)

I always wondered if one could receive WWVB with a properly tuned antenna and a 192kHz audio DAC. 192kHZ is sufficiently over the nyquist rate for 60kHz, so assuming SNR is above the sensitivity of the DAC it should be possible, at least in theory.

There are a number of software based receivers that use a soundcard to copy VLF stations.

Do a search on SAQrx or visit https://www.qsl.net/dl4yhf/speclab/vlf_rcvr.htm

Right, I was wondering if direct receiving of LF would be possible with a higher-sampling rate sound-card.

If I wanted to make my own clock, what's the best low power method of reading the time data? Are there some sort of ultra low power chips that can run on just w little solar panel?

https://www.amazon.com/CANADUINO-Atomic-Clock-Receiver-60kHz...

then the rest of it is basics for small PV charge controller, dc-dc converter, battery (such as to keep one good quality 18650 at an 85% float voltage)

Your amazon link shows 'unavailable'. The original source has a number of WWVB receiver products: https://www.universal-solder.ca/product-category/atomic-cloc...

I purchased the Everset ES-100 dev kit from them last year, but haven't put it together yet. I am curious how much better the BPSK decoder for WWVB will work in Eastern Canada.

I have an "atomic clock" that receives WWVB and runs for years on 2 AA batteries. It's 20 years old so what you want is eminently doable.

I retrofitted a WWVB clock movement in my kitchen clock. It's quite nice not having to set it up when changing the battery or when DST shows up.

One of my favorite papers from long ago was "Dating Events in the Vicinity of Leap Seconds" published by the National Bureau of Standards, the precursor of NIST.

That memo became less relevant once I married.

With more recent techniques, a much higher bitrate could be sustained. I think it would be possible to supply a ~100 kbit/s broadcast channel on longwave that could be received in most of North America reliably, with a simple IC receiver.

I'm not exactly sure what you'd use that for, admittedly.

That would consume a significant amount of spectrum, like on the order of 200,000 kHz or 0.2 mHz.

DRM+ broadcasts digital audio over medium, short, and also long wave. It has 30 - 180 kbit/s depending on coding, in a 100 kHz channel.

Using 10 or 50 kHz down there as a data broadcast channel would not be an issue, as it's not like the longwave band is exactly crowded.

Have you ever listened to VLF with a good receiver and antenna? It is chock full of signals.

Sadly, it appears that many of the beacons are going away: https://www.dxinfocentre.com/ndb.htm

You're not going to fit 100kbits/second into the few hertz of bandwidth at 60,000 Hz that WWVB currently uses to send 1 bit per second, no matter how magic the technology is.

Reply on news.ycombinator.com