Why do reports say GPS Receivers will only be a problem for the weekend?

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Why do reports say GPS Receivers will only be a problem for the weekend?

I keep reading reports that say the GPS Receivers will only cause problems for the weekend? I would think non-compliant receivers will be non-compliant for more than a few days.....

Any input would be appreaciated.

-- mmmm (mmmm@aol.com), August 20, 1999


Why do reporters open their stupid mouths to start with?????????

-- rambo (rambo@thewoods.com), August 20, 1999.

Boaters, hikers preparing for Y2K-style glitch with high-tech compass 8/19/99 Author: Associated Press

MARINA DEL REY, California -- Stuart Prince doesn't carry maps or charts when he sets sail off the Southern California coast. He has no radar on his 30-foot (9-meter) boat and doesn't know how to navigate by the stars.

He does have a compass, but to plot a course it's 100 percent Global Positioning System or nothing.

And that could be a problem this weekend.

The handheld satellite navigation devices in use all over the world could malfunction when the system resets its clocks as scheduled Saturday.

GPS, originally designed for the military, has been used for at least a decade by aviators and boaters, who can easily become disoriented out in the open.

Now the devices are booming in the commercial market, often offered as a perk in luxury cars as a mapping device. Hikers use GPS to recall a favorite campsite or apply it like a high-tech trail of bread crumbs to get back to their starting point in featureless terrain or bad weather.

"I guess I'd just go east until I hit land," Prince, 39, said as he enjoyed a beer with a buddy on his docked boat and fiddled with his GPS receiver. "It's such a fantastic tool. Everyone is so dependent on it."

Because of this possible Y2K-like glitch, the receivers may take longer to pinpoint a location, be off in their calculations or be unable to find a location, which is usually displayed on a map or in latitude and longitude.

The reason for the problem is that GPS receivers determine a location by using signals from three to 24 satellites. To account for variations in the Earth's orbit and rotation, they need the exact time, determined by counting the weeks since Jan. 5, 1980 -- up to 1,024.

But GPS is reaching its maximum number of weeks, and time clocks on the locators are resetting to zero.

Most receivers built since 1993 were designed to handle the rollover. Manufacturers have offered upgrades of older ones, but for the unprepared, GPS may turn into GRS -- Getting Rescued Saturday.

Email us at y2kfeedback@idefense.com Copyright (c) 1998

-- mmmm (mmmm@aol.com), August 20, 1999.

i'm voting for "bought and paid for"

-- sarah (qubr@aol.com), August 20, 1999.

GPS Changes Coming Earlier Than Some Expected 8/18/99 Author: Tim Dobbyn (Reuters)

WASHINGTON -- Boaters and other civilian users facing possible disruption in the Global Positioning System (GPS) this weekend need to be ready a few days earlier than previously anticipated, the U.S. military said Tuesday.

Although attention has been focused on the Aug. 21-22 reset of the GPS internal clock to zero, some users of the satellite-based navigation system may start to experience problems as early as Thursday, both the U.S. Air Force and the Coast Guard warned.

The reason is that a regular update of location information to the 27 satellites in the system beginning Aug. 19 also contains new time information that could cause some older GPS receivers to misinterpret which satellites they are "viewing."

GPS plays an increasingly important role in civilian life, including airline operations, truck fleet tracking, recreational boating and computer maps in cars.

The August date rollover for GPS occurs because the system was designed to ignore calendar dates, but keep precise time measured in seconds and weeks.

Only 1,024 weeks were allotted from Jan. 6 in 1980 before the system resets to zero. The event has been compared to GPS' own version of the Year 2000 computer glitch that arises because too little memory was allocated to the year in dates.

Most recently manufactured GPS receivers are capable of handling both the satellite update and the system's internal date rollover but some units made 1994 or earlier are in doubt.

Some receivers may not work at all, others will take more time to locate satellites and others may display inaccurate positions, times or dates.

"Users need to check their equipment regularly over the next few days," said Ronea Alger, chief spokeswoman at Los Angeles Air Force Base, that runs the GPS program.

The Coast Guard is urging boaters and other users that include private pilots to play safe and always have more than one navigation tool available. Boat/U.S., a boat owners' organization, said it was concerned by the recent emergence of Thursday as a problem after it had spent months sounding warnings about the Aug. 21-22 clock reset.

Spokeswoman Becky Squires said people on voyages expecting to get a few extra days out of their GPS equipment could be at risk. "I think that's a little disturbing," she said.

Boat/U.S. has advised its members that most GPS units made after 1994 are ready for the GPS date rollover.

Coast Guard Master Chief Petty Officer Rick Hamilton said the Aug. 19 problem could have the biggest impact on the increasing number of users who rely on the precise time information generated by GPS to coordinated communications networks.

"We're talking about cellular phone systems, fax and page systems and some power grids," said Hamilton. "We call it the invisible GPS community."

The Aircraft Owners and Pilots Association (AOPA) played down the risk to aviation from the GPS changes.

AOPA spokesman Drew Steketee said the control panel units used in instrument flight conditions were subject to government orders to be end-of-week compliant while hand-held GPS units sometimes used under visual flight rules were meant as backups only.

"People in the aviation industry have foreseen this date for some time, the press is just waking up to it this month," Steketee said.

------------------------------------------------------------------------ Copyright 1999 Reuters Limited. All rights reserved. Republication and redistribution of Reuters content is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon.

-- mmmm (mmmm@aol.com), August 20, 1999.

It's not quite clear to me. Most of the "experts" in GPS seem to be able to write equations, formulas, and computer code much better than they write English (or whatever vernacular). Apparently, the week counter is only one factor in calculating elapsed time. Apparently, other factors (including one [?] referred to as the ephemeris, and the the almanacs updated periodically, unless "ephemeris" is the GPS- geekspeak for "almanac") are also used, and they contribute to a re- synchronization.

-- Lane Core Jr. (elcore@sgi.net), August 20, 1999.

Sounds suspicious to me. Experts huh? What the hell do they know? Experts are paid sound bites. GPS could be a real problem. That's my take on it.

-- DOWNtheROAD (foo@foo.com), August 20, 1999.

No one and I mean NO ONE has addressed the GPS rollover problem regarding banks, telcos and data transfers.

Why isn't anyone paying attention to this??????

I don't give a flying f^ck at a rolling donut what happens to little navigation systems. I mean - I don't want anyone to get lost but I don't think a bunch of lost yachts or hikers constitute a global crisis.

Cascading bank failures on the other hand....

-- R (riversoma@aol.com), August 20, 1999.

"We're talking about cellular phone systems, fax and page systems and some power grids," said Hamilton. "We call it the invisible GPS community."

Well this could get interesting.

Heres a question - is the net dependant on the GPS for data transfers?

-- R (riversoma@aol.com), August 20, 1999.

Lane --

Ephemeris used to be the term used for satellite position data back when I was interested in that business. Don't think it's changed. It's the data that tells the system where to look for a satellite.

-- de (delewis@inetone.net), August 20, 1999.

de, then "ephemeris" and "almanac" are two terms referring, basically, to the same information?

-- Lane Core Jr. (elcore@sgi.net), August 20, 1999.

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