Most accurate device time?

goodValue

Eyeful said:

You can play around with this.
 Use the search bar at top of page to find time somewhere else (example New York).
https://time.is/

Doesn't this have the same problem as trying to use the BBC pips on a digital radio?

I think the problem is called latency.

I didn't see the site discuss any technique compensating for latency, and so you don't know how inaccurate their time is.

Undervalued

goodValue said:

Eyeful said:

You can play around with this.
 Use the search bar at top of page to find time somewhere else (example New York).
https://time.is/

Doesn't this have the same problem as trying to use the BBC pips on a digital radio?

I think the problem is called latency.

I didn't see the site discuss any technique compensating for latency, and so you don't know how inaccurate their time is.

As far as I know the problem only exists on digital radio, basically because your DAB radio is a computer and has to process the information it receives.

On old fashioned analogue radio there should be no delay, assuming all the equipment at the transmission end is still analogue too! The signal gets along its wires and through radio waves at the speed of light!

Analogue TV AFAIK has all been switched off.

Eyeful

goodValue said:

Eyeful said:

You can play around with this.
 Use the search bar at top of page to find time somewhere else (example New York).
https://time.is/

Doesn't this have the same problem as trying to use the BBC pips on a digital radio?

I think the problem is called latency.

I didn't see the site discuss any technique compensating for latency, and so you don't know how inaccurate their time is.

1. Its accurate for my needs, why does it have to be more accurate than this?
2. Casio’s main radio-controlled watch line is called Wave Ceptor and start at about £150.
3.  The Citizen Caliber 0100 Eco-Drive (non-atomic watch) costs approximately £5,900 GBP, is accurate to +/- 1 second a year. 
4.  The BBC time pips on analogue radio do not suffer a delay. It the digital radios that suffer from a delay.

bob2302

goodValue said:

Eyeful said:

You can play around with this.
 Use the search bar at top of page to find time somewhere else (example New York).
https://time.is/

Doesn't this have the same problem as trying to use the BBC pips on a digital radio?

I think the problem is called latency.

I think with DAB the delay comes from buffering the audio. Latency on the internet is typically ~10mS.

time.is displays the synchronization accuracy and it's typically showing about +/- 100mS.

unforeseen

I think most of the DAB delay comes from processing an analogue audio stream to digital and it can be 1-2 seconds
You only need to swap between an analogue radio station and its DAB version to experience that difference. 

goodValue

I think with DAB the delay comes from buffering the audio. Latency on the internet is typically ~10mS.

In the Android link posted earlier, it gives a value of up to 2.5 seconds for latency on an Android phone, and that is after compensation techniques have been used.

Frozen_up_north

As a “time nut”, as frequency and time enthusiasts are often called, can I add my 2p worth?
1. My iPhone displays the time that is “spot on”. I don’t know if an Android phone has the same accuracy, but suspect it has.

2. Do not trust “pips” from the BBC, even on analogue radios, and definitely not on DAB or from the time shown on any TV channel. Our local BBC medium wave/FM station used to play a recording of the pips and they were often 2 or 3 seconds out, and varied from day to day! Not sure about Radio 4 on long wave or FM.

3. Some radio controlled clocks only adjust the time once or twice a day and can wander around. The best check/adjust the time every hour and are very good.

4. Using an analogue radio (without digital signal processing), the RWM time signal from Moscow is good, as are the signals from MSF at Anthorn on 60 KHz. The RWM frequencies and schedule is detailed at:
https://en.m.wikipedia.org/wiki/RWM

5. The internet time setting utility NetTime can be configured to adjust your PC time as often as you like from a variety of internet time servers. It is free and works fine under Windows 11, even though it is quite old software.
http://timesynctool.com/

Using a combination of the above you can easily confirm which are accurate by eye and ear. I haven’t tried to measure to a few milliseconds as I don’t need that level of accuracy.

Eyeful

https://time.is/

 The Time.is server is continually synchronized to atomic clock time, providing a precision of about 0.02 to 0.10 seconds under optimal conditions depending on your internet connection and computer load.

PHK

Undervalued said:

goodValue said:

Eyeful said:

You can play around with this.
 Use the search bar at top of page to find time somewhere else (example New York).
https://time.is/

Doesn't this have the same problem as trying to use the BBC pips on a digital radio?

I think the problem is called latency.

I didn't see the site discuss any technique compensating for latency, and so you don't know how inaccurate their time is.

As far as I know the problem only exists on digital radio, basically because your DAB radio is a computer and has to process the information it receives.

On old fashioned analogue radio there should be no delay, assuming all the equipment at the transmission end is still analogue too! The signal gets along its wires and through radio waves at the speed of light!

Analogue TV AFAIK has all been switched off.

Anyone with more than one analogue radio in the past will know this is not correct. 

The speed of a signal in cabling is less than  the speed of light in a vacuum plus you need to factor in the reaction times of various components in the set, the length of cabling  and the natural capacitance and inductance of wiring. 


(Plus even though the speed is fast it's still finite and takes a measurable time. And if setting a clock from the pips you have to add your own reaction time. It takes between 0.01 and 0.2 seconds to recognise a sound and another 0.2 to 0.5 seconds for your brain to initiate the movement)

molerat

Checked my devices.  Laptop was, say, 30 secs, mobile 29 secs and digital radio controlled clock 28 secs.  Re synced laptop and it then matched mobile.  I will check again in the morning when the clock has had time to re sync.