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A reliable source of timing and synchronisation standards and services

WWV transmits audio "ticks" once per second, to allow for accurate manual clock synchronization. These ticks are always transmitted, even during voice announcements and silent periods. As an exception, no tick and no silent interval is transmitted at 29 or 59 seconds past the minute. In the event of a leap second, no tick is transmitted during second 60 of the minute, either. On the minute, the tick is extended to a 0. The beginning of the tone corresponds to the start of the minute. The second tick preempts other transmissions, but does not get a silent zone.

Voice announcements of time of day are made at the end of every minute, giving the time of the following minute beep. WWVH makes an identical time announcement, starting 15 seconds before the minute tone, in a female voice. When voice announcements were first instituted, they were phrased as follows: "National Bureau of Standards, WWV; when the tone returns, Eastern Standard Time is [time in hour format].

The announcement was changed again to the current format in WWV transmits the following second voice announcements in lieu of the standard frequency tones on an hourly schedule: [16]. Additional time slots are normally transmitted as a standard frequency tone, but can be preempted by voice messages if necessary:.

WWVH transmits the same information on a different schedule. WWV identifies itself twice each hour, at 0 and 30 minutes past the hour. The text of the identification is as follows:. National Institute of Standards and Technology time: this is Radio Station WWV, Fort Collins Colorado, broadcasting on internationally allocated standard carrier frequencies of two-point-five, five, ten, fifteen, and twenty megahertz, providing time of day, standard time interval, and other related information.

They begin after the 1-second minute mark and continues until the beginning of the WWVH time announcement 45 seconds after the minute. WWVH is similar, but exchanges the two tones. WWV also transmits a Hz tone, a pitch commonly used in music A , the musical note A above middle C during minute 2 of each hour, except for the first hour of the UTC day. WWVH transmits the same tone during minute 1 of each hour. No tone is transmitted during voice announcements from either WWV or WWVH; the latter causes WWV to transmit no tone during minutes 43 through 51 inclusive and minutes 29 and 59 of each hour.

Time of day is also continuously transmitted using a digital time code , interpretable by radio-controlled clocks.

Gathering and Times

This code is similar to, and has the same framework as, the IRIG H time code and the time code that WWVB transmits, except the individual fields of the code are rearranged and are transmitted with the least significant bit sent first. Like the IRIG timecode, the time transmitted is the time of the start of the minute. Also like the IRIG timecode, numeric data minute, hour, day of year, and last two digits of year are sent in binary-coded decimal BCD format rather than as simple binary integers: Each decimal digit is sent as two, three, or four bits depending on its possible range of values.

A single bit or marker is sent in this way in every second of each minute except the first second The first second of each minute is reserved for the minute marker, previously described. It takes one minute to transmit a complete time code. Like the WWVB time code, only the tens and units digits of the year are transmitted; unlike the WWVB time code, there is no direct indication for leap year.

WWV (radio station)

Thus, receivers assuming that year 00 is a leap year correct for year will be incorrect in the year On the other hand, receivers that assume year 00 is not a leap year will be correct for through The table below shows the interpretation of each bit, with the "Ex" column being the values from the example above. The example shown encodes day 86 March 27 of , at UTC. The day of year normally runs from 1 January 1 through December 31 , but in leap years, December 31 would be day , and day 86 would be March 26 instead of March The time code contains three bits announcing daylight saving time DST changes and imminent leap seconds.

Before the next local time after that, the bits will be the same. Receivers in the Central, Mountain, and Pacific time zones have one, two, and three more hours of advance notice, respectively. During a leap second, a binary zero is transmitted in the time code; [23] in this case, the minute will not be preceded by a marker.

The earliest formal record of WWV's existence is in the October 1, issue of the Department of Commerce's Radio Service Bulletin , where it is listed as a new "experimental station" [25] assigned to the Bureau of Standards in Washington, D. C, with the randomly issued call letters of WWV. However, it also noted that "The bureau has been experimenting with the wireless music for several months, and has reached such an advanced stage of development that further investigation to them is useless, and they are going to discontinue the concerts.

At the end of , WWV's purpose shifted to broadcasting standard frequency signals. These were an important aid to broadcasting and amateur stations, because their equipment limitations at the time meant they had difficulty staying on their assigned frequencies. Testing began on January 29, The first quartz resonators that stabilized the frequency generating oscillators were invented in the mids, and they greatly improved the accuracy of WWV's frequency broadcasts.

In , WWV was nearly shut down. Its signal could only cover the eastern half of the United States, and other stations located in Minneapolis and at Stanford University and the Massachusetts Institute of Technology were slowly making WWV redundant. The station's impending shutdown was announced in , but it was saved by a flood of protests from citizens who relied on the service. Later, in , WWV underwent an upgrade. Its transmitter, now directly controlled by a quartz oscillator, was moved to College Park, Maryland.

A year later, the station was moved again, to Department of Agriculture land in Beltsville, Maryland. WWV was nearly destroyed by a fire on November 6, The frequency and transmitting equipment was recovered, and the station was back on the air with reduced power on November Congress funded a new station in July , and it was built 5 kilometres 3. WWV began broadcasting second pulses in , but initially these were not tied to actual time.


Voice announcements started on January 1, , and were broadcast every five minutes. By this time, WWV was broadcasting on 2. A binary-coded decimal time code began testing in , and became permanent in WWV moved to its present location near Fort Collins on December 1, , [39] enabling better reception of its signal throughout the continental United States. WWVB signed on in that location three years earlier. The voice used on WWV was that of professional broadcaster Don Elliott Heald until August 13, , when equipment changes required re-recording the announcer's voice.

The one used at that time was that of another professional broadcaster, John Doyle , but was soon switched to the voice of KSFO morning host Lee Rodgers. John D. Kraus , a professor at Ohio State University , knew that a meteor entering the upper atmosphere leaves in its wake a small amount of ionized air. This air reflects a stray radio signal back to Earth, strengthening the signal at the surface for a few seconds.

This effect is known as meteor scatter. Putting the most public services at the front of the chopping block is common fare for bureaucrats being pissey. It created public outrage and the true story gets buried in the noise, and if all goes well they get the same funding that they used to or even more. They closed at 4PM and weekends. They pretty much made it so it was near impossible for a person working days to use the library. That created a big stink, but the people that funded them put out a stink of their own.

They set minimum standards and also it got out what some of the employees were making. That did not help donations any. In the end they wound up being forced to make the best of it and make more rational decisions as to what services and paychecks to trim. It is like public radio, they plead poverty, but look at what some of those people on the air begging for money make a year, and now they could replace all of them with eager to break into the business people for free.

NIST are fully willing to sacrifice old projects to keep new ones afloat. I only hope they make the right decisions. Surely someone on Hackaday. This is what I thought as well! It would not be too difficult to have an Arduino ,or perhaps a Raspberry Pie if the power is needed, to sync with NTP and produce the signal…. Amen to that.

Unless you want to have a few vans with directional antennas to converge on your house, do not mess with this frequency. You can easily affect e. If you do need to retrofit an old clock, it is better to emulate the demodulated signal and inject it using a wire directly into the clock past the receiver part. John Blackthorn — As far as I know most of our street lights are dusk-to-dawn on a light sensor, although I imagine that some streetlights are linked to time tables for civil twilight, to avoid being set off by a bird landing on the sensor, snow, etc..

Um if it is shut down then these devices will be wrong anyways, and would need replacing, so there would be no devices that would be affected by a diy signal? So, what signal would actually be impeded by my illegal transmitter? Of course, it would be quite stupid to have some military equipment rely on an external signal that can be disturbed by the enemy. I literally linked it earlier in the thread.

If they do retire the service, they should officially permit short range transmitters on its old frequency. Basically, an untrusted sources has exactly enough power to correct the estimated error, plus a tiny bit more to correct for what previous bad clocks might have done. I actually quite like this idea We have networks set up by comcast and others that already span major cities with wifi. Only problem is that wifi is way more power hungry when compared to GPS or WWVH receivers, would need quite a bit of code skillz to keep the receiver from eating up all the battery life.

I remember when the Autochron annunciator in my local office switched over to using GPS. I asked the switchman what was gonna happen to the WWV B? The problem here is, that there are many internal clocks in alarm systems, AC control, industrial control, etc. When the signal goes silent, those clocks will start to wander off, leading to all sorts of weird effects.

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And, the next major blackout after switching off WWVB could do a lot of damage. Probably a case of out of sight, out of mind. NIST never advertised it services, what it does or what it offers the community. These budget cuts were probably made by bureaucrats with no idea what the agency does. I chose to use that on a clock repair because I felt confident that it would carry on working for the next several decades whereas GPS seems to always be up in the air.

In fact a clock that I made that depends on MSF60 was featured on here only a few weeks ago!. Well, the WWVB signal is simple and unencrypted. I see a hacking project. Would be a neat idea to maybe have an article offering an overview about them all over the world. For those of us still enjoying amateur radio, these make excellent HF propagation beacons.

It would be a shame for these to be turned off. Agreed, that was going to be my two cents. Not just hams, but people who enjoy shortwave listening use these as frequency standards and to check propagation. What I would like to see is a list of all of the time stations worldwide and their operating frequencies, that would be helpful. Wikipedia has a list. No one will miss them? Eventually, GPS timing will be small, low power, and cheap enough to use in such things. Using the phone instead of a proper wristwatch is like a step back into the old time of pocket watches.

Only without the watch chain to pull it out quickly, although some people could use their headphone cable as the have permanently plugged their ears with the headphones. It already quit working for me years ago, probably too much interference from all the cheap electronics that are on the market. Or not have it at all, for that matter. WWVB seems to fit most closely the description of the station in Ft. Maybe when they brought in the new modulation scheme. It seemed an acknowledgement that WWVB is getting lots of use setting clocks.

RFC - Network Time Protocol (Version 2) -

It is confusing, WWVB not specifically mentioned, yet the station most likely to affect the most people if turned off. If WWVB does go dark, I think I might rig up a low-power 60 kHz oscillator at home, and switch it on and off to mimic what my clocks are expecting.

There goes the only use left for a Shortwave radio. They might as well shut down the whole HF spectrum and do some broadband net on it.

There they go again. The Federal Government in action. Now they want to pull the plug on everyone that has invested in these clocks. The government stupidly shut down all the LORAN stations a few years ago to save money, so now if GPS is lost due to attacks or solar storms, we have no reliable time or navigation source. Way to go Federal government. Is this the Deep State in action?

Upgrade more a power bill issue. Actual transmitter upgrade was contribution of old Navy VLF equipment previously used to signal submarines. Think mentioned power bill may be more of an issue for NIST buget than any equipment costs. Ever consider how much it costs just to power a kw transmitter 24 hours a day?

Now consider that few even wear watches anymore, let alone self setting models. Most use their phones for timekeeping. Will just get spent on something else. I will be very irritated if they shut these down to save peanuts. I agree with an earlier poster who suggested that there will be a lot of unexpected industrial uses of these radio time references. I know that here in the UK there are master clocks at railway stations and in signal boxes which rely on MSF60 to provide an accurate time references.

I think people have forgotten that it was the railways that drove the adoption of Standard Time to protect against collisions! There will be a lot of other stuff which needs this. I live in a suburb of London, and was very surprised to find that my local electricity substation uses MSF as a time reference in-spite of also having a GSM module for remote monitoring. Although this proposal is in the US, I have signed your petition, and if this ever becomes an issue in Europe, I hope some of you will sign ours!

May this never come to pass! Kudos to the previous posters who have articulated so well the many good reasons for keeping these stations operating. My goodness, what the bloody hell is going on in that infernal sausage factory District of Columbia? The sky is not falling. A later bill, the National Institute of Standards and Technology Reauthorization Act of , was reported out of committee in June with no changes to laboratory programs.

It will probably take several months before a final appropriations bill for NIST becomes law, but so far Congress has ignored the severe cuts of the original NIST proposal. What are the lobbyists for the manufacturers saying and doing? They have a large financial interest in this technology.

How would you like to fork over half a grand and have the main selling point vanish in a few months without warning? It would be like buying a new cell phone and having it suddenly drop to 3G. This site uses Akismet to reduce spam. Learn how your comment data is processed.