GPS Satellite(s) down?

I was checking out a new installation on my Pocket PC, and wanted to make sure that everything was working OK...

And my GPS on it is showing about a half mile error. And the best I can get is 2D fix, even out in the open... and with this GPS I usually get a 3-D fix even inside.

At first, I thought that it might be from transferring all my PPC programs to a new memory card and I somehow glitched the mapping software on it, but trying it out on my laptop setup it shows it off in the same place.

And on both devices, logging the GPS position (sitting still) shows it wavering all over the place every couple of seconds by about + - 500ft.

So, If you other GPS owners in the US have a minute, can you get out your units and see if you are experiencing any errors? Thanks!

Mine shows me to be about 1/2 mile west of my actual position. It was working perfectly last time I used it only 2-3 days ago, and it has been sitting safely in a drawer since then, so it shouldn't have been damaged..

Or maybe the Govt. is jinxing the GPSs for security purposes or a test or something.?????

PS, can you believe that I bought a new 2Gig SD memory card for $49.00!!

http://www.newegg.com/Product/Product.asp?Item=N82E16820211029

They got one gig ones for $27.00 too.

I wonder if they're playing with Selective Avalibility (jamming)...

Yeah...brb...

Nope. Mine is as accurate as ever...Magellan eXplorist 500.

BTW, if it was just a satellite outage, they have a few spares up there to take up the slack.

Oh...and another highly-useful link -- if you know how to interpret the data:
http://tycho.usno.navy.mil/gps_datafiles.html
ftp://tycho.usno.navy.mil/pub/gps/gpstd.txt

JM-99

Checked the GPS forum:
http://www.gpspassion.com/forumsen/default.asp?group=2

No one over there is talking about any problems yet.

Just checked again... Now, It has me pretty close to where I really am, but it is still jumping around like crazy.

heh, I was JUST NOW testing out my new Gamin 60csX

Sats up working Perfectly for me,

I am in the BASEMENT of my house, reading 22 ft accuracy. :devil:

~John

Hmm, Interesting.

It is working pretty well now, I'm exactly where I am and only jumping around about 5-10 ft at a time. . Get an intermittant 3-D fix.... Have to go back outside and see if it locks on better.

Wonder if 'they' can program the satellites to mess fixes up just in certain areas? I'm pretty close to White Sands Missile range, so I can see why they would want to be able to screw up GPSs in that area upon occasion.

If they have that much control on a selective basis, maybe they were just testing it, or there was something real going on.

Oh Well...

Thanks to all those that participated in this little exercise . :thanks:

Funny, I just stepped out front with a Garmin E-map. It's normally pretty good (a 12 channel unit). It took 4 or 5 minutes to aquire the sats, and even though it had 4 good locks with strong signals (I was standing on the porch to stay out of the rain so it only saw 1/4 of the sky) it indicated 2d and 95ft accuracy. That's not quite normal.

SF Bay Area, Ca, 8:30 PM.

Wonder if something is up?

Daniel

Outside I get a solid and fairly accurate 3-D lock now, only about 15 ft off (usually this setup is a little more accurate than that, surprisingly, for a really inexpensive Compact Flash GPS)...

Turn on 'sky view' and stand in the same spot, in the clear, and the 'satellites' are blinking like Christmas tree lights set on random blinks. I'm in the footprint of 10 of them, have up to seven locked on at any given moment, but a few seconds later, only three, and occasionally two are 'lit up', then a few seconds later, five, six or seven are on. #16 & #23 are the only satellites staying on constantly.


Satellite #3 is the only one I haven't connected with, but it is right on the edge of my footprint.

(sorry if my terminology isn't quite right, I'm not QUITE a GPS geek, so I have to make up words as I go.
---------------------------------------------------
Oh, Thanks Jumpmaster for that Tycho link... I thought there was something like that out there, but I couldn't remember where it was.

Funny thing is, THAT page is down:
"The server at tycho.usno.navy.mil is taking too long to respond."

I got the main entry page for a moment, but it is down now too.

Just checked. Both Magellen and antique Raytheon fluctuating some. Checked www.spaceweather.com and find no unusual solar activity.

Earlier today my Garmin Etrex Legend was doing it's usual 15 feet or so. It's far too late for me to go outside and check it now.

jtice said:

heh, I was JUST NOW testing out my new Gamin 60csX

Sats up working Perfectly for me,

I am in the BASEMENT of my house, reading 22 ft accuracy. :devil:

~John

Click to expand...

These SIRF new units ROCK!

please make us more envy, what else you can do that "old" gps can't?


Pablo

Too late? Just grab a flashlight ! ! !

Sorry. Had to day that.

Daniel

Silviron said:

Mine shows me to be about 1/2 mile west of my actual position. It was working perfectly last time I used it only 2-3 days ago, and it has been sitting safely in a drawer since then, so it shouldn't have been damaged.

Click to expand...

Experience any earthquakes lately?

Nope, no earthquakes. The nearest active rift or fault line is a hundred miles away. It tends to have nearly continuous microquakes, but the seismos directly on it can just barely measure them. Ones you can actually feel , standing right on the rift average only one - three every ten years or so.

I don't think we have had a measurable quake here since our big 12,003 ft high volcanic mountain settled down about 10,000 years ago:

Finally got in to Tycho website: here is what the "Satellite Health Page" modified Thursday, March 30, 2006 10:16:52 PM says:
______________________________________
UNITED STATES NAVAL OBSERVATORY (USNO)


SATELLITE HEALTH CODE INFORMATION

****************************************************************

GPS SATELLITE HEALTH CODES:

CODE INDICATION
-.-. -.-.-.-.-.
00 ALL SIGNALS OK
01 ALL SIGNALS WEAK, 3 - 6DB BELOW SPECS
02 ALL SIGNALS DEAD
03 ALL SIGNALS HAVE NO DATA MODULATION
04 L1-P SIGNAL WEAK
05 L1-P SIGNAL DEAD
06 L1-P SIGNAL HAS NO DATA DEMODULATION
07 L2-P SIGNAL WEAK
08 L2-P SIGNAL DEAD
09 L2-P SIGNAL HAS NO DATA DEMODULATION
10 L1-C SIGNAL WEAK
11 L1-C SIGNAL DEAD
12 L1-C SIGNAL HAS NO DATA DEMODULATION
13 L2-C SIGNAL WEAK
14 L2-C SIGNAL DEAD
15 L2-C SIGNAL HAS NO DATA DEMODULATION
16 L1 & L2-P SIGNAL WEAK
17 L1 & L2-P SIGNAL DEAD
18 L1 & L2-P SIGNAL HAS NO DATA DEMODULATION
19 L1 & L2-C SIGNAL WEAK
20 L1 & L2-C SIGNAL DEAD
21 L1 & L2-C SIGNAL HAS NO DATA DEMODULATION
22 L1 SIGNAL WEAK
23 L1 SIGNAL DEAD
24 L1 SIGNAL HAS NO DATA DEMODULATION
25 L2 SIGNAL WEAK
26 L2 SIGNAL DEAD
27 L2 SIGNAL HAS NO DATA DEMODULATION
28 SV IS TEMPORARILY OUT - DO NOT USE THIS SV DURING THIS PASS
30 SPARE
31 MORE THAN ONE ANOMALY
____________________________________________

That kind of explains it, huh?

Although I'd like to know WHY nearly everything is like that.....

Oh, wait, Weren't the French or the Chinese supposed to be launching several of their own GPS satellites this week? Seems like I read that somewhere very recently.

Maybe they are actually trying to bring down our GPS system. (I'm kidding about that last part... or AM I?)

Uh, silveriron? Excuse me, but that appears to be a list of possible error codes, not the current status.

Note that each is slightly different.

Daniel

If I understand this map correctly, the southwestern US is suffering from some minor 'dilution of precision', to use the government's term.

Dunno if this explains your readings or not, but I learned something looking for it, so thanks!

gadget_lover said:

Uh, silveriron? Excuse me, but that appears to be a list of possible error codes, not the current status.

Note that each is slightly different.

Daniel

Click to expand...

OH, DUH!


I thought those were the satellite numbers... even I should have known there aren't that many GPS satellites up.

What a maroon

Silviron said:

OH, DUH!


I thought those were the satellite numbers... even I should have known there aren't that many GPS satellites up.

What a maroon

Click to expand...

I think there are about 14 GPS satellites

chevrofreak said:

I think there are about 14 GPS satellites

Click to expand...

More like 29 (including several spares), or at least that's what it was last time I checked...edit: that's what it says here:
http://tycho.usno.navy.mil/gpscurr.html

I also wanted to clarify that "Selective Availability" is not the same thing as "Jamming".

JM-99