That could be it. Broadcast delay. Makes sense.

Acquiring high-resolution time stamps - Win32 apps
Windows provides APIs that you can use to acquire high-resolution time stamps or measure time intervals.
That could be it. Broadcast delay. Makes sense.
I thought it was 10 seconds. But my memory is probably hazy. Yeah it was probably 15.
BEEEP.
Windows 11. It works on Win 10 too.
Right click on the Windows icon in the lower left hand corner of your computers display.
On the popped up list of things find ‘settings’ and left click it.
On the left side of the window that opens find ‘Time & language’ and left click that.
A list of things will display and one will be called ‘Date & time’.
To the far right of the box that ‘Date & time’ shows up in will be a right pointing arrow. Left click that.
It’ll take you to another list with and option under the title of ‘Additional settings’. Under there will be a box called ‘Sync now’.
To the far right of that box will be a button called ‘Sync now’. Left click it.
You’ll see the rotating arrow thing and if it completes successfully a check mark will appear to the left of the button.
In the left side of the ‘Sync now’ box you’ll now see ‘Last successful time synchronization: date time’ that will reflect the date and time you did the sync.
Just below that you’ll see ‘Time server: time.windows.com’
The time will be correct to the second.
844-1212 was time. 844=TI4, TI standing for TIME.
I think any other numbers could be substituted for 1212 for either.
In Champaign Illinois in the mid-70s the time and temperature number wasn’t from the phone company, but Busey Bank.
Dylan mentions the time operator in “Talkin’ World War III Blues.” The dreamer calls the operator of time just to hear a voice of some kind.
“When you hear the beep, the time will be 3 PM.”
“She said that for over an hour, and I hung up.”
In my neighborhood, suburban Maryland, 555-1212 was directory information, which for many years was a live operator who would read out your requested number. Eventually it was automated: they would listen to your request, say “Hold for the number,” and an automated voice would read it out.
Same here. My experience was that (area code) 555-1212 was directory assistance. Live, then later recorded info.
Any NFL football history fans here? In the mid-1990s I dialed 325-555-1212 and asked for Sammy Baugh, NFL Hall of Famer from the 1940s. 325 is the area code for Rotan TX. I got a number, dialed it out of the blue, and to my pleasant surprise it was the legend himself who answered the phone! We had a pleasant conversation and I arranged to mail a football history coffee table book to him for his autograph. He did! I was thrilled.No, I didn’t ask him what time it was.
We had a 976 number here in Chicago for time: 976-1616. As a 976 number, I believe it incurred an extra fee like other 976 numbers did. 976-1212 was weather.
down to the exact second
Most hams just use the Windows clock.
Any discrepancy is below my physical perception limit.
I am going to opine that if you need to know the time within a second (or even somewhat better), this is not some high-precision problem, so you may as well grab the time from the Windows clock set to NTP, a time-broadcast radio station, the telephone (the USNO also used to have a service for dial-up computer modems so you would not have to push a button by hand with your variable reaction time), it doesn’t really matter, as long as you avoid some of the pitfalls mentioned like listening to the radio over a delay line or mistaking GPS time for Universal Time.
I don’t know about Windows 11, but in earlier versions I have always resorted to a registry hack to turn on the seconds on the little clock in the bottom right.
This is essential in some of the troubleshooting work I do. We often have people on conference calls who are about to demonstrate “the slow thing” in a complex application, and I want to have precise timestamps so that I can find the eyedropper of relevant network traffic in the firehose of noise. Accurate timestamps help to narrow that down.
Some of our servers are so busy that they can roll over an 8GB capture buffer in minutes, so knowing how to find the traffic down to the nearest second is crucial.
I went to college well before the internet, and part of my CE curriculum was surveying. We did a field exercise to find true north, which involved meeting at about midnight setting up our transits to train on Polaris. The prof had an ephemeris to give us the exact time that Polaris would be at its maximum deviance from north so he had a radio set to the official time. When the magic time hit and we all had Polaris in the crosshairs, then we could turn the transit the known deviance that Polaris was from true north and presto we then had the instrument running exactly true north. I don’t know what the frequency of the radio station was or even if it’s still operational.
Getting Windows to provide reasonably-precise (microsecond) time stamps should not be so hard
Windows provides APIs that you can use to acquire high-resolution time stamps or measure time intervals.
If those timestamps need to be in sync with the actual time, that is when you need to set up a GPS receiver correctly.
I don’t know what the frequency of the radio station was or even if it’s still operational.
The various WWV stations still broadcast on a bunch of frequencies. I just checked and they are definitely on the air.
That kind of precision is definitely far above my paygrade.
In the work I do, we often are telling a business user on the call “Make sure you say ‘click’ when you click the button that starts the slow thing” and we hope that they do. When they do, I glance at the system clock and write “start: hh:mm:ss”, and then repeat this when they say the task is done.
So anything more precise than a second is wasted.
Besides, in network analysis, packet capture timestamps are not going to agree at the microsecond level.
It’s kind of like a woodworker using a micrometer to do what they really need a tape measure for.
if you need to know the time within a second (or even somewhat better), this is not some high-precision problem
A (very prolific and talented) youtuber curiousmarc has a bunch of vids about (among many other fascinating space, flight, nav, instrumentation topics) atomic clocks and getting them sync’d with GPS. It’s, like, 85% out of my league but damned if I can’t feel my brain getting bigger watching his vids.
I’ll just post this latest one from a week ago but he has lots and lots.
I don’t know what the frequency of the radio station was or even if it’s still operational.
The simulation @DavidNRockies posted above plays the WWV audio. I’ve never heard it so clearly but it definitely sounds just right, very satisfying.
Whoa. Do various devices then make an adjustment by subtracting 18 seconds from the GPS time?
I have a Garmin GPS-capable smartwatch. Normally it syncs to your phone for time, but there’s an option to manually sync to GPS. So I just did that, and then synced my computer via the default time server, and they’re within a second of each other. So I’m gonna say a typical GPS device knows about the leap-seconds.
Oh yes…I forgot one other niche time thing I do: darkroom work.
(I realize that this is for relative time and not current absolute time, but it’s a cool tangent)
Darkroom work involves multiple timers, because you really are timing different things with different requirements.
For developing the film, there’s a handy-dandy app that uses The Massive Dev Chart to provide times for agitations and so forth.
When using the enlarger, you really want an electronic (or at least electric) timer that triggers the lamp. I have one of those big Gralab timers with an analog dial that you twirl into position before starting. This needs to be accurate to the second.
Finally, when developing the print, it’s all about times of a minute or two, accurate to the nearest few seconds. For this I use a “Smiths Timer”, a cool wind-up timer that looks like one of those chess clocks, with a start and stop button on the top.
Finally, when developing the print, it’s all about times of a minute or two, accurate to the nearest few seconds. For this I use a “Smiths Timer”, a cool wind-up timer that looks like one of those chess clocks, with a start and stop button on the top.
This takes me back. My father was a keen photographer and did his own darkroom work.
I still have the clockwork timer he used, made by ‘Smiths English Clock systems’.
It sees a lot of use in the kitchen.
The thing is built like a battletank; it will probably still be working perfectly decades after I am gone…
The thing is built like a battletank; it will probably still be working perfectly decades after I am gone…
If you ever have any issues, I took mine apart and documented the process for future Smiths Timer users.
That’s one of those videos that I make not so much for views, but mainly to help the next guy, as most people will only find the video when they are searching for how to do something very specific, such as how to take apart a Smiths Timer!
I built my time server on a Raspberry Pi with a GPS piggyback board. It grabs time from all the satellites it “sees”. Everything on my network points to it for time sync.
There used to be a time phone number when I was a kid that I would call, I think run by the phone company.
They had that in other countries too. A story that made the rounds ages ago was that a vengeful ex-girl friend called the time phone number in Tokyo and did not hang up before leaving the room and closing the door. If the story is true the former boy friend must have received a very expensive phone bill.
The atomic clock video sent me on a rabbit hole of his related ones.
Umm, thanks?
Brian
Ha, I watched his Bendix mechanical flight computer series last week. Before I know it, I’m looking for synchros, 400 Hz generators, and surplus aircraft instrument clusters on ebay.