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Has the Military encrypted the GPS signals?


mudhuggers

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Which story do you want?

 

Two satellites recently died suddenly, 21 and 22. Replacements are planned, but may take several months or longer. They just can't snap their fingers and make that happen, satellites must be built, rocket launches must be planned in advance, etc.

 

The other story: it is all a plot by the bush administration (or is it hillary?) and the oil companies to force a one-world government on the unsuspecting masses. The satellites were secretly snatched by black UFO's launched from Area 51, crewed by Elvis, Jimmy Hoffa, and Amelia Earhart.

 

Pick the story of your choice. I like the second one better.

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No, there's been no evidence of SA ever having been re-activated.

 

Satellite 22 is out of hospital, alive and well with a still overpopulated constellation compared to the specs. I'd hate to hear the complaints if ever the system ever gets towards the lower minimum end of the specs icon_razz.gif

 

Accuracy even in Brahrain is currently running around 3 metres @ 95% and Kibutz (Israel) a little over 3 metres.

 

For the 48 hour period 23/11 to 25/11 the local accuracy here (my place) was 2.15m CEP or 2.95m RMS or 4.4m @ 95% depending on which value sounds the best even though they are mean the same thing.

 

Cheers, Kerry.

 

I never get lost icon_smile.gif everybody keeps telling me where to go icon_wink.gif

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quote:
Originally posted by tmcgowan:

Well at least the government won't be able to lock onto the chip they inbedded in my brain!

 

icon_wink.gif


 

TMC's out innocently caching, gets a good satellite lock, and troops off to the cache. Suddenly, as the distance-to-waypoint dwindles to 35 feet, a big purple laser beam slashes out of the sky and fries a nearby tree. "Whew!" TMC thinks out loud, "Good thing 21 & 22 are sick! Otherwise, I'd be toast. Now, where's that confounded cache?"

 

Always wear proper caching safety equipment!

60748_1200.jpg

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I've noticed less accuracy in the last week. I've no idea if this could be the cause, but I read something interesting in a book called "GPS Made Easy" by Lawrence Letham.

 

He says that during the Gulf War, the GPS constellation was changed to provide more coverage in the Middle East. This left less coverage in areas such as California, and people there noiced their receivers were not working as well as they used to.

 

Just a thought...

 

George

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quote:
Originally posted by nincehelser:

I've noticed less accuracy in the last week. I've no idea if this could be the cause, but I read something interesting in a book called "GPS Made Easy" by Lawrence Letham.

 

He says that during the Gulf War, the GPS constellation was changed to provide more coverage in the Middle East. This left less coverage in areas such as California, and people there noiced their receivers were not working as well as they used to.


 

During the Gulf war GPS was still in the "construction phase" and consisted of only 16 satellites (3 Block 1A, 3 Block 1R & 10 Block IIA's). These still only gave a 2D fix (minimum 3 sats) for 19-20 hours each day and 15 hours of 3D fixes.

 

These weren't changed about per say as much as the new craft that were launched during the conflict were put in orbits that best suited the middle east. The satellite that was launched on the day of the invasion (Aug 2) was activated in a record 22 days.

 

NavStar was only declared operational in 1995 so back in 1990 things were far from perfect considering war is a 24 hour job.

 

Cheers, Kerry.

 

I never get lost icon_smile.gif everybody keeps telling me where to go icon_wink.gif

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I am an Air Traffic Controller, and the GPS signal CAN vary on a day to day basis. The government DOES still use SA selectively in certain areas, but we get a notice when they do that giving the times and affected area. We used to get RAIM (Remote Autonomous Integrity Monitoring) data that would give us information on GPS availability for a 14 day period, broken down into 15 minute increments, but the contract expired and we're SOL until they find some money and award another contract.

 

Communists worship Satan, Socialists think perdition is a good system run by bad men, and Liberals want us all to go to hell because it's warm there in the winter.

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quote:
Originally posted by Raoul Duke:

.... The government DOES still use SA selectively in certain areas, but we get a notice when they do that giving the times and affected area ....


 

If that being the case then that would have to be unclassified information.

 

Where does these notices originate from especially with regards the "specific use" of Selective Availability.

 

By specific use of "Selective Availability" I mean actual SA as opposed to other types of warnings like http://www.aopa.org/whatsnew/newsitems/gpstesting.html, which is not SA.

 

Cheers, Kerry.

 

I never get lost icon_smile.gif everybody keeps telling me where to go icon_wink.gif

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