NavList:

David C, you wrote:
"But........the pips are an interesting 100 year old tradition. If it does not cost very much to broadcast them then maybe RNZ should continue the tradition. "

I agree. Public time-keeping has significant symbolic value. It does matter. It's not as if Big Ben in London serves any practical function when every single citizen in Greater London carries an atomic clock repeater (phone) every hour of every day. Yet they pay to keep it running as accurately as possible. Otherwise, anarchy.

Consider a town with a public clock in front of the town hall, or maybe a bank with a clock out front. They put these clocks up for a reason --not really time, but something symbolic. It doesn't take much effort, especially today, to keep the clock running and to keep it displaying accurate time. Then one day it stops. The town or bank does nothing. The project for the repair is put on a back burner. Cost estimates grow higher and higher. But the time is now wrong twenty-four hours a day, minus two minutes or so when it's "close enough" by chance. How can you trust a town government or a bank management that can't mind and care for such basics?

These radio pips serve no real practical purpose any longer. Many such "pips" have been dropped in recent years, both because they're no longer practical, and because the result on the receiving end is often delayed by ten or more seconds by various processes. Yet they do matter, right? They yell out "continuity", "tradition", hell, they yell out "civilization" itself (!) with their simple beep, beep, beeeep. As for me, I am a rare holdout listening to "AM" band CBS news from Manhattan (only sometimes, and only when driving). It's familiar and sedate, and it's straight-forward news most of the time. At the top of every hour, there's a tone to mark the hour. It's not an exact match to the hourly UTC rollover, and I check it occasionally to see if it's eight seconds or more or less out. But it's the attempt that matters. The tradition is reassuring (and so is the static on the AM band, but that's a different sort of tradition... the "music" of random noise).

How accurate does broadcast time need to be? Obviously specialized functions like in financial trading require accurate synchronization. And we need time to a second or two in celestial navigation. But mere mortals? What do they demand of time? In a few recent years, when I've been out at midnight on New Year's Eve, I have watched with studious interest as crowds celebrate the exact second of midnight (it's "3... 2... 1... Scream!!"). But of course, they don't celebrate the actual exact second. Despite all those near-perfect atomic clock repeaters that we all carry around, it's not the second of midnight, but rather the somewhat delayed broadcast --about 15 seconds delayed typically-- of the event in some public center, like Times Square in New York City. And that seems to be close to the level of "error" that mere mortals comfortably accept. The minutes matter. People care about getting the time right to the minute. They don't care about ten or fifteen seconds of net offset here and there.

But wait, what about time in sporting races and similar events?? Then it's down to milliseconds. So... aha! Gotcha! But it's not time that's being measured in such cases. It's elapsed time. We care about the delta-t, the change in time, but not the exact absolute t. If a sprinters race is supposed to start at 1:05:00, and the winner completes the course in 1m 45.35s while the next runner comes in at 1m 45.45s (a tenth of a second later), no one is going to call foul if we learn after the fact that the race actually started at 1:05:20. The "t" doesn't matter if the "delta-t" is accurate.

Frank Reed