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REW
05-02-2000, 12:00 PM
I just got off the phone chatting with my cousin - who designs GPS receivers for the aircraft industry.

He stated the following:
SNA - has been turned off by the government -- effective last night at
midnight.

This means that the typical accuracy of the GPS receivers in lat / long will
be better by about a factor of 10. It also means that the altitude accuracy
(the most inaccurate measurement) will be better by a factor of about 4.

This means that on the average -- the typical GPS receiver will spot a person
anywhere in the world at a spot of 10-30 meters (typically closer to 10 than
30 meters.

The currently implemented system of DGPS system will be left intact. As I
speculated - DGPS corrects not only for SNA changes, but it also corrects for
tropospheric inaccuracies, clock inaccuries, and any other anomolies that may
occur.

With the currenly implemented DGPS system and with SNA turned off -- the
expected positioning accuracy of the system will allow 1-3 meters accuracy.

Talk about finding the hump on the bolder in the middle of the ocean.!!!!

Another big part of this discussion is the passage of the emergency GPS
positioned system of 911. My brother has been lobying for the passage of
this to happen. He works for a start up company in Ca. that has designed a
GPS system that will fit into every cell phone in the world. With ths system
installed, and with SNA turned off -- a cell phone /GPS (inserted) can dial
911 -- and emergency response teams will be directed to the cell phone --
with a guarenteed accuracy of 10-30 meters. Hows that for finding the lady
in the snow storm.

The third part of the equation is this --
The government has developed a modification to the GPS positioning system --
so that they can selectivly scramble or disable -- various areas of the
globe. The example was given, is that they can effectively black out (as far
as GPS coverage is concerned ) all of the Balkens -- yet let Jet liners work
just fine as close as 100 miles to the area of black out. (The government is
always figuring ways to protect its population).

Good news for all of us who have relied more and more on the accuracy of
these systems.

p.s.

If any of you haven't already -- take a spin with one of the new Auto -
talking - colored GPS sytems put out by Garmin and other manufacturers. Many
of the rental car companies have installed these sytems in their rental cars.
They then use chips that are city specific. The chips contain detailed
routing information to resturants, hotels, local attractions etc. Progran in
the destination, and the GPS will verbally direct you there, in the quickest
or most senic way possible. The system will warn of upcoming turns,
intersections, on and off ramps.

Now if someone will do the same thing for our lake maps -- We can have a nice
voice directing us to the 3rd hot spot next to the last culvert on the right
bank of the last hotspot. What they will think of next??

Bottom line -- better tools at less expensive prices for all of us to enjoy
our hobby.

Take care

REW

buzzer IA
05-02-2000, 04:12 PM
Hey REW,
All I know is, when I get my GPS, I want you to

show me how to use it..LOL
buzzer IA

Scott_in_kc
05-02-2000, 04:41 PM
REW- is this a permanent shut off of the SNA (I know nothing is final when it involves the government?)

For the type of fishing I have been doing here in KS & MO I have'nt really needed one yet. Although now that it may have the ability to "find the rock on the hump in the middle of the ocean" I may have to get one on board. Any suggestions on handheld vs. mounted. It would be great to have one that I could use in the car, boat & trail bike.

acp
05-02-2000, 04:55 PM
For a graphical look at the sifference SA on and off looks like, check out the following URL:

#####://#####.igeb.gov/sa/diagram.shtml

Later....

Al

acp
05-02-2000, 04:56 PM
Here's the URL again with spaces added:

h t t p://w w w.igeb.gov/sa/diagram.shtml

Later....

Al

REW
05-02-2000, 06:12 PM
It is permenant until the government changes its collective mind.

Take care

REW

REW
05-02-2000, 06:15 PM
The best suggestion is the following:
Read the instruction manual on the new GPS unit - cover to cover a couple of times.

Then -- assuming that is a hand held unit -- keep it with you in the car for the summer. Use it as often as you can - both in the car planning trips etc. After you get a few hours in using the unit -- everything will become second nature.

The problem that most folks have --is simply the fact that they haven't used it when they get on the water,and then they don't want to spend time reading the manual or experimenting with the settings.

They simply want to fish. Learn all about the unit, how to set it up, and use it before hitting the water.

Take care

REW

RMB
05-02-2000, 07:25 PM
You're right on target about practice use BEFORE getting on the water. Keep it in the car with you for 1-2 weeks and try out all the functions, and it doesn't take long to get the swing of things. I honestly wouldn't be on my favorite waters without it. PS: Once again your wealth of info. is greatly appreciated!