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Bookers Bourbon
and a good cigar
Picture of Johnny 3eagles
posted
We have 4 "Atomic" (Radio controlled) clocks in our house and 1 Casio multi band watch. All have been 100% accurate and always self adjust for Daylight Savings and Standard time changes.

Except for tonight. Two of the clocks on the North end of the house already changed to DST the other two and the watch have not. It is only 626pm (1826) here in the Central time zone.



BIDEN SUCKS.

If you're goin' through hell, keep on going.
Don't slow down. If you're scared don't show it.
You might get out before the devil even knows you're there.


NRA ENDOWMENT LIFE MEMBER
 
Posts: 7120 | Location: Arkansas  | Registered: November 06, 2010Reply With QuoteReport This Post
Optimistic Cynic
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As I understand it, the radio signals these clocks rely on are not error-corrected, of encoded with a reliable protocol, just are, basically, tickers. It is the job of the clock to make sense of the signals it is receiving which may be corrupted by all sorts of random noise. Radio, what are you going to do? GPS time signatures are much more dependable in this regard, although they have their own weaknesses. We have learned a lot about reliable radio communications since the WWV time signal was set up in 1945, but it is still using the same signal it did back then.
 
Posts: 6455 | Location: NoVA | Registered: July 22, 2009Reply With QuoteReport This Post
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Posts: 3507 | Registered: May 30, 2011Reply With QuoteReport This Post
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quote:
Originally posted by architect:
GPS time signatures are much more dependable in this regard, although they have their own weaknesses.

There are 4 atomic clocks on each GPS satellite. I ran a GPS clock on FreeBSD for a number of years. I used a Garmin marine grade GPS receiver that received the PPS signal, into a 9 pin serial port, and then to NTP (network time protocol). I graphed the clock and it maintained time within +/- 4 microseconds of UTC. Not bad for a home made solution, with the built in overhead of the serial port and cheap crystal oscillator on the motherboard.



When in doubt, mumble
 
Posts: 10782 | Location: South Congress AZ | Registered: May 27, 2006Reply With QuoteReport This Post
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quote:
Originally posted by henryaz:
quote:
Originally posted by architect:
GPS time signatures are much more dependable in this regard, although they have their own weaknesses.

There are 4 atomic clocks on each GPS satellite. I ran a GPS clock on FreeBSD for a number of years. I used a Garmin marine grade GPS receiver that received the PPS signal, into a 9 pin serial port, and then to NTP (network time protocol). I graphed the clock and it maintained time within +/- 4 microseconds of UTC. Not bad for a home made solution, with the built in overhead of the serial port and cheap crystal oscillator on the motherboard.


To think all I had to do was strap a Garmin Forerunner to my wrist and start one of the distance related activities.


I've stopped counting.
 
Posts: 5643 | Location: Michigan | Registered: November 07, 2008Reply With QuoteReport This Post
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Two of your clocks are taking Lombardi time to a new level.
 
Posts: 10913 | Location: SWFL | Registered: October 10, 2007Reply With QuoteReport This Post
Bookers Bourbon
and a good cigar
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BIDEN SUCKS.

If you're goin' through hell, keep on going.
Don't slow down. If you're scared don't show it.
You might get out before the devil even knows you're there.


NRA ENDOWMENT LIFE MEMBER
 
Posts: 7120 | Location: Arkansas  | Registered: November 06, 2010Reply With QuoteReport This Post
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