Six things about the pips, a familiar sound to listeners of BBC Radio.
1. Thursday marks 80 years since the BBC first broadcast its pips.
2. The pips, correctly known as the Greenwich Time Signal, have not indicated Greenwich Mean Time since 1972, the adoption of "international atomic time".
3. Before the BBC started using the pips, a pianist in a studio would play the tune of the Westminster chimes, synchronising the "bong" with the clock in the studio.
4. The first pip is broadcast at the 55th second, with the beginning of the sixth indicating the start of the next minute.
5. The signal on analogue radio is calculated to be accurate 100 miles from Broadcasting House (ie in Leicester, Swindon, and Calais). Technical problems (which are being addressed) mean the signal is not yet accurate on digital radio, digital TV or internet.
6. The final pip, lasting half a second, is longer than the other five, which last a tenth of a second. The reason for this is that atomic time is calculated independently of the Earth's spin (which is basically the method for calculating GMT), and occasionally an extra second needs to be added to compensate. To prevent people setting their watches prematurely, the final pip, whether it is the sixth or the seventh, is slightly longer (just like this item).
Some of your comments:
I'm surprised you haven't chosen to mention or play the BBC Radiophonic Workshops homage to the pips "Time To Go" written by pioneering electronic musician Delia Derbyshire. Probably the only tune that uses the pips to full effect.
Richard Rackham, UK
Do you have a favourite pip? Mine is the third. Don't really know why but it sounds better than the rest to me.
John Roberts, UK
Can't the pips be made available for download to mobile phones. Now that would be a cool ring tone.
Dutch public radio used the same pips in the past, but a couple of years ago they changed to three pips: two short ones followed by one long one. The last one coincides with the start of the new hour. Too many people mis-counted the six pips while trying to set their watches...
David van Kemenade, UK (Dutch ex-pat)
I miss it!
For an expat the pips had a nice comfortable and reliable ping to them. 80 years old ...well done....I'm 82
I remember Arthur Askey's comments that when he was new at the BBC his job was to polish the pips ready for the next time they were used. Great days...
Chris C, UK
Many episodes of On The Hour used the pips to good effect. More, please!
Alex J Thomas, UK
If the final pip is half a second long at which point does the next minute actually start? Important stuff for those of us who like to keep our sundials properly calibrated. Incidentally, they sound like 'peeps' rather than 'pips' to me, but then I live in Scotland and the pip has been stretched as it heads north.
Kevin Waite, UK
I had a Panasonic microwave which signal the end of cooking with four short pips and one long one, almost exactly the same pitch and duration as the BBC ones. Very comforting.
Sadly I think it won't be long before our old friends, the pips have to be phased out. If you listen on analogue radio, they are correct, on DAB about 2 seconds late, on the internet, anything up to 20 seconds late. Regretably you can't rely on them any more. Perhaps they should be consigned to R4 Long Wave for we sailors - along with the other "less popular" strands, like the Shipping Forecast, the cricket, Yesterday in Parliament and the Daily Service!
Neil Eccles, UK
Another BBC repeat.
Tom UK, UK
Fascinating Pip Fact: The pip-tone is a 1kHz sinewave, and is also used in many psychoacoustic experiments. Wowee!
Duncan, York, UK
I love how the main BBC TV News themes incorporate the pips. Symbolic, nostalgic, well recognised yet with a modern flare. Just like the BBC on the whole really!
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