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Conventional clocks can be misleading

As a practical matter, the time most people (in the States) live by is set by the phone company, which is usually ~4 minutes off from "official" atomic colock time.

Do you have a cite for this? My cellphone (from Nextel/Sprint) syncs to the local tower and is less than 1 second off from NIST's official US time. Even in the past I remember phone company "at the tone the time will be..." services to be within a minute (my father worked for the weather service, I had access to atomic clock time when i was at his office after school.)
 
Do you have a cite for this? My cellphone (from Nextel/Sprint) syncs to the local tower and is less than 1 second off from NIST's official US time. Even in the past I remember phone company "at the tone the time will be..." services to be within a minute (my father worked for the weather service, I had access to atomic clock time when i was at his office after school.)
I called 853-1212 and compared the time to http://www.time.gov/timezone.cgi?Pacific/d/-8/java

It was to the second.
 
Do you have a cite for this?

Local observation, so I guess YMMV.

I bought a computerized telescope some time ago, and I keep trying to "bag" STS, ISS and various other satellites. I tried setting the 'scope according to the time shown on the phone's Caller-ID box, but things were never synchronized; that's when I discovered the 4-minute difference. I still have trouble because I haven't got around to rigging a direct connection between the computer and the telescope. This is the first season I've had a laptop, so maybe now it's a bit more practical.
 
Local observation, so I guess YMMV.

I bought a computerized telescope some time ago, and I keep trying to "bag" STS, ISS and various other satellites. I tried setting the 'scope according to the time shown on the phone's Caller-ID box, but things were never synchronized; that's when I discovered the 4-minute difference. I still have trouble because I haven't got around to rigging a direct connection between the computer and the telescope. This is the first season I've had a laptop, so maybe now it's a bit more practical.

Interesting. I don't have a land line anymore so I can't test caller id time here. If you don't mind paying for a long distance call you can try calling the atomic clock directly, of course if your laptop keeps good time you can sync it too:

http://tf.nist.gov/stations/sig.html

for some reason that page is down for me at the moment, here's the google cache:
http://64.233.167.104/search?q=cach...ov/stations/sig.html&hl=en&gl=us&ct=clnk&cd=2
 

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