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Time up for atomic clocks
The Register ^ | 24 April 2006 | Chris Williams

Posted on 04/24/2006 11:32:23 AM PDT by ShadowAce

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To: Izzy Dunne
Yes, since 1983. It takes a while to sink into my brain.

I can relate. The only reason I know about it is because I've been extremely fascinated with time for as long as I can remember. At one time, I had an HP test and measurement catalog (it was a hardback volume) that had a couple of atomic clocks I'd drool over. Coulda been mine for only $18K!

Some day I'm going to figure out how to manufacture more of it (time), then I'll be rich!

61 posted on 04/24/2006 2:10:35 PM PDT by zeugma (Anybody who says XP is more secure than OS X or Linux has been licking toads.)
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To: zeugma
FWIW, there are 4.7027904e+13 furlongs per light year.

I prefer Furlongs per fortnight as the standard unit of velocity.
62 posted on 04/24/2006 2:30:49 PM PDT by TalonDJ
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To: ShadowAce
Having a guaranteed accurate timepiece set to exact time is nothing but frustrating to the average user.

Back in the 70's, I was an engineer on the Texas Instruments Watch program. (Remember those red LED numbers you had to push a button to see -- if the ambient light wasn't too bright?)

All through our facility, we had a network of master clocks that were phase-locked-loop synchronized to WWV. On that network, we had sockets into which we could insert the watch modules, which were then automatically synchronized with the master clocks.

We also had sockets connected to extremely accurate frequency counters, and a closed-loop adjustment station that would set the frequency of the module's "tuning fork" crystal oscillator to exactly 32,768.000000 Hz. (That is 215 -- an excellent frequency for dividing down via a set of digital registers...)

All of us wore "On-the-arm Test" sample watches, and, of course, I hand-selected a module with less than 100 milliseconds (1/10 sec) per month drift for mine. That meant that I had what was unarguably one of the most accurate (and most accurately set) watches in the world.

But, "out in the world", I noticed that it was usual for waatches and clocks to be no more accurate than +/- ten minutes! Whenever I claimed that I had the exact time, some bozo would say, "No, mine is right -- I just set it with [naming a local radio or TV station] this morning.

Then I started checking radio stations' time "hacks". The typical station's time announcement went something like this:

Starting some time within ten seconds of the hour, the announcer would say something like,

"At the tone -- brought to you courtesy of Bubba Wilfred Hacklefratzl's Barbecue Emporium, Cathouse, and Laundromat -- at 102334 Southwest Zonkywhistle Avenue in lovely downtown Cowflop City, the time will be exactly XX:XX PM...BEEP!

The "BEEP!" almost never came within ten seconds of the hour.

So, in frustration, I gave up on the whole "accurate wristwatch" bit. And, now that I'm retired, I don't even own one of the darned things...

Oh -- when I need the time, I check my laptop -- or the GPS receiver I use to set it...

63 posted on 04/24/2006 2:41:57 PM PDT by TXnMA (Remember the Alamo! Remember Goliad! Repeat San Jacinto!)
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To: Izzy Dunne

Electronics and integrated circuits, for one. Particle physics, for two. Accurately accounting for the slowing of the earth's rotation about its own axis and the sun, three. More arcane stuff than even this.


64 posted on 04/24/2006 2:44:41 PM PDT by tom h
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To: Lurker

Probably with a microwave referigerator.


65 posted on 04/24/2006 3:03:10 PM PDT by arthurus (Better to fight them OVER THERE than here.)
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To: Chuck54

That is an incredible bulb.


66 posted on 04/25/2006 9:30:27 AM PDT by Ernest_at_the_Beach (History is soon Forgotten,)
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