BBC Pips

[Jona26]

I thought BBC Pips were synchronized with some central time signal, as are times on mobile phones.

This morning on Radio 4 the 09:00 pips were played when the time on my mobile phone was showing 09:01 and it ticked over to 09:02 just a few seconds later.

Which is more accurate?

 

[krus_aragon]

I thought BBC Pips were synchronized with some central time signal, as are times on mobile phones.

This morning on Radio 4 the 09:00 pips were played when the time on my mobile phone was showing 09:01 and it ticked over to 09:02 just a few seconds later.

Which is more accurate?

To my knowledge, the pips on analogue Radio 4 are accurately synchronised to GMT. On DAB, there's a short (unavoidable) delay from the Analogue-Digital and Digital-Analogue conversion process. This has led the BBC to ruminate whether to keep the pips in the future, but I'm not aware that they came to a conclusion.

If you're streaming Radio 4 over the internet, then as well as the A/D-D/A delay, you'll also have a delay as packets of internet data are buffered so they can be played in the correct order.

In short, analogue radio should be spot on, and DAB is within a few seconds.

 

[Jona26]

Thank you - that makes sense. I was streaming R4 via my mobile whilst I was travelling.

 

[DarloRich]

as an example try listening to a radio 5 football commentary on the radio, then move to a streaming service and see what the delay is like

 

[kermit]

I noticed some years ago that Digital Radio is out of sync with analogue, and that "The Pips" therefore no longer held value in terms of accuracy. I think that sometimes the lag can be quite a bit more than a few seconds, but I could be wrong.

 

[krus_aragon]

I noticed some years ago that Digital Radio is out of sync with analogue, and that "The Pips" therefore no longer held value in terms of accuracy. I think that sometimes the lag can be quite a bit more than a few seconds, but I could be wrong.

For DAB (or DAB+) varieties of digital, the lag should be constant. For digital streaming, the lag will definitely vary.

Part of the rumination at the BBC that I mentioned above was whether they should time the pips so that analogue broadcasts are correct, and DAB slightly off, or the other way around. It was in this context (and that of the variable timing of streaming) that there was talk of whether to bother keeping them in the future or not.

Mind you, we were originally going to start tuning off analogue radio broadcasts by 2015, and then 2019, but take-up of digital radio hasn't been anywhere fast enough, so it's indefinitely postponed. We've only got one DAB radio in our house (a hand-me-down), which is usually used in FM mode anyway.

 

[Geezertronic]

as an example try listening to a radio 5 football commentary on the radio, then move to a streaming service and see what the delay is like

It appears to be the same if I watch (for example) a football match on Sky Sports via UltraHD and if my neighbour watches normally, he cheers when a goal is scored before I see it scored

 

[CarltonA]

This thread caused me to look up the "Rugby Time Signal" which corrects my clock each night. Apparently this was switched off in 2007. A lag of over twelve years before I found out about it.

https://en.wikipedia.org/wiki/Time_from_NPL_(MSF)

 

[edwin_m]

This thread caused me to look up the "Rugby Time Signal" which corrects my clock each night. Apparently this was switched off in 2007. A lag of over twelve years before I found out about it.

Is your clock still correct?

I guess the time lag on DAB would depend on the receiver, as some may have more delay than others. If that's so then it couldn't be synchronised absolutely.

 

[CarltonA]

Is your clock still correct?

Yes, the signal now comes from Anthorn in Cumbria.

 

[robvulpes]

So, if you have a DAB radio with a clock incorporated in the display, is the clock kept accurate to 'Anthorn time' or is it only as accurate as the DAB broadcasting of the BBC pips (i.e. slightly late)? (My DAB radio alarm clock updates its time at the first minute after turning on to a DAB channel.)

 

[krus_aragon]

So, if you have a DAB radio with a clock incorporated in the display, is the clock kept accurate to 'Anthorn time' or is it only as accurate as the DAB broadcasting of the BBC pips (i.e. slightly late)? (My DAB radio alarm clock updates its time at the first minute after turning on to a DAB channel.)

This sounds like a job for a clockwatcher listening to radio 4...

 

[Puppetfinger]

There still are radio stations around the world playing audible time signals, mainly on HF for ships and aircraft to observe chronometer error.

 

[robbeech]

It's interesting when i arrive at work in the car listening to Radio 4 on DAB, and walk through the door to hear it streaming in an office, often a good 30 seconds behind. I've noticed the difference between Analogue and DAB, it's significant but certainly not as much as that. An A to D and a D to A conversion is a few milliseconds tops. It's other processing that means DAB is later than Analogue rather than a conversion.

 

[DelayRepay]

It's interesting when i arrive at work in the car listening to Radio 4 on DAB, and walk through the door to hear it streaming in an office, often a good 30 seconds behind. I've noticed the difference between Analogue and DAB, it's significant but certainly not as much as that.

I notice the difference between FM and DAB when I'm listening to BBC Local Radio in my car. I listen on DAB, but the radio switches to the same station's FM feed for travel bulletins if I have the TA button on. When the bulletin finishes on FM and the radio goes back to DAB, you normally get the last few words repeated.

 

[mikeg]

Ah, the pips. Yes there's a significant encoding and also a small decoding delay on DAB, will be rather sad if they're canned after any digital switchover though. I do have to despair at the recent trend for 'crashing the pips', i.e. mixing them in with music or speech, which has become the norm on radios 1 and 2. This was always considered extremely bad form and rightly so.

 

[swt_passenger]

Is it technically feasible for BBC just to mute the pips on streamed versions of a radio channel?

 

[najaB]

Is it technically feasible for BBC just to mute the pips on streamed versions of a radio channel?

Yes, it is. But if there's no clear majority platform then they lose their practical value. On top of which, most people have a mobile or computer synchronized to a NTP source anyway.

 

[mmh]

Yes, it is. But if there's no clear majority platform then they lose their practical value. On top of which, most people have a mobile or computer synchronized to a NTP source anyway.

Their cultural value is far greater than their practical value, and probably has been for at least 40 years. The sort of thing you fiddle with at your peril as a BBC controller!

 

[najaB]

Their cultural value is far greater than their practical value, and probably has been for at least 40 years.

They still had practical value up until the smartphone explosion. I certainly used BBC World service pips to set/check my clocks back home well into the 1990s.

 

[sefyllian]

So, if you have a DAB radio with a clock incorporated in the display, is the clock kept accurate to 'Anthorn time' or is it only as accurate as the DAB broadcasting of the BBC pips (i.e. slightly late)?

The DAB signal includes an accurate embedded timecode, and that's what your clock uses. Nothing to do with the pips, which are, literally, just noise.

Their cultural value is far greater than their practical value, and probably has been for at least 40 years. The sort of thing you fiddle with at your peril as a BBC controller!

Bear in mind the pips are really only used by Radio 4, so not that many people these days actually hear them or even know what they were for. I doubt many Radio 4 listeners really care either way.

Remember there used to be live clocks on-screen to introduce every news bulletin on BBC One, instead of the normal globe? They were ditched for the same reasons as above – digital broadcasting meant they were no longer accurate – but who cares now? There was a minor fuss about it at the time, but most people just accept the world’s moved on.

Every now and again you do get someone (a backbench Tory MP, usually) moaning that since the launch of BBC News, which is broadcast overnight on BBC One, there’s no God Save the Queen at the end of transmission any more. But most people happily live without it!

 

[MotCO]

It's interesting when i arrive at work in the car listening to Radio 4 on DAB, and walk through the door to hear it streaming in an office, often a good 30 seconds behind. I've noticed the difference between Analogue and DAB, it's significant but certainly not as much as that. An A to D and a D to A conversion is a few milliseconds tops. It's other processing that means DAB is later than Analogue rather than a conversion.

I've also noticed a difference in timing between my portable DAB and alarm clock DAB. THe speech on one is repeated a few seconds later on the other. How does this occur?

 

[mmh]

I've also noticed a difference in timing between my portable DAB and alarm clock DAB. THe speech on one is repeated a few seconds later on the other. How does this occur?

Different digital to analogue audio processing speeds between the two radios.

A downside to DAB for people like me who sometimes have the radio on in different rooms.

 

[AM9]

Different digital to analogue audio processing speeds between the two radios.

A downside to DAB for people like me who sometimes have the radio on in different rooms.

Yes, I've found that the Pure DAB radios that I've had over the years tend to be about 1/4s after the others, Panasonic, Roberts and Denon but as that is present on FM then I suspect that their audio processing has more delay, particularly as their radios tend to be predominately battery powered. The DVB radio broadcasts are also delayed. So in my experience, excluding the Pure extra lag, the delays are about:
FM radio - less than 10ms, based on bandwidth and distance from the Wrotham transmitter
DVB radio - about 2.5 seconds behind FM
DAB radio - about 3.5 seconds behind FM
iplayer radio/Sounds - anything between 1 and 2 minutes behind FM depending on packet size, network traffic and Wi-fi strength (where applicable).

 

[Tom B]

Their cultural value is far greater than their practical value, and probably has been for at least 40 years. The sort of thing you fiddle with at your peril as a BBC controller!

Ironically, I remember some years ago the long serving continuity announcer Peter Donaldson (now sadly deceased) being a strong advocate for their removal because of the widespread use of digital radio etc.

Cultural value is perhaps part of the reason why the Shipping Forecast continues to go out, so mustn't complain! In recent years, though, other traditions have been edged out - for example, the UK Theme at 0530, and the playing of Lillibulero on the World Service.

There's quite a strong emphasis on Radio 4 on not crashing the pips (one announcer broadcast a large f--- when accidentally doing so a few years ago I think). Radio 2 plays them at 5pm and at 7pm only - they have a much more laid back approach to talking over things.

Every now and again you do get someone (a backbench Tory MP, usually) moaning that since the launch of BBC News, which is broadcast overnight on BBC One, there’s no God Save the Queen at the end of transmission any more. But most people happily live without it!

Said MPs need only listen to 4 at 00.59 - it is played daily when transmission ends for the night! I know that Radio 1FM, 2, and 5Live are all 24 hour services so there is no close down per se.

 

[krus_aragon]

Every now and again you do get someone (a backbench Tory MP, usually) moaning that since the launch of BBC News, which is broadcast overnight on BBC One, there’s no God Save the Queen at the end of transmission any more. But most people happily live without it!

I'm quite surprised on the few occasions I'm driving late enough at night to hear Radio 4's closedown, and that anthem suddenly blares out at me!

 

[telstarbox]

For DAB (or DAB+) varieties of digital, the lag should be constant. For digital streaming, the lag will definitely vary.

Part of the rumination at the BBC that I mentioned above was whether they should time the pips so that analogue broadcasts are correct, and DAB slightly off, or the other way around. It was in this context (and that of the variable timing of streaming) that there was talk of whether to bother keeping them in the future or not.

Mind you, we were originally going to start tuning off analogue radio broadcasts by 2015, and then 2019, but take-up of digital radio hasn't been anywhere fast enough, so it's indefinitely postponed. We've only got one DAB radio in our house (a hand-me-down), which is usually used in FM mode anyway.

Are most cars sold with anologue rather than DAB radios still?

 

[MotCO]

What's the difference between DAB and DVB?

 

[najaB]

What's the difference between DAB and DVB?

Digital Audio Broadcast and Digital Video Broadcast.