3rd Captivate, GPS Works - Captivate General

I've had 2 Captivate's from AT&T store here in Seattle and returned them both because of the well known GPS problems. I had posted a question earlier questioning what evidence made people think that it was a software vs hardware issue. After returning the second one I went back to my iPhone 3GS but couldn't handle it anymore and got a 3rd Captivate from Best Buy (they were $50 cheaper). Running all stock this GPS works nearly perfect and gets MUCH better signal than the previous two. I've run GPS Test by Chartcross Ltd on all 3 of them to view the satellite SNR and Accuracy rather than just looking at maps or nav...on the previous units I would see signals at best in the mid 20s to mid 30s and they would sit there forever and once in awhile get a lock. This was even walking outside on clear sunny days.
On this new unit that I've had for about 5 days now I'm getting mid 30s to mid 40s on the SNR even on rainy days, and even in the car. It consistently locks on to 5+ satellites and consistently is able to get 16-32ft accuracy while driving down I5. I've used My Tracks to track 5 trips back and forth to work (about 30 minutes each way) and get near perfect tracks each time. Google Nav works just as well as my in car nav system.
So, given this HUGE difference between units that I have personally used does it seem like there is still room for this being software not hardware? Might there be something software wise on my new unit that could possibly help?

Related

GPS Problems? Yup everyone

http://free-pc-guides.com/news/first-att-samsung-captivate-owners-report-problems-with-gps-02887
This is such a sensationalist article. There aren't any problems with the GPS. You're supposed to use a GPS outside, and even inside, mine got a signal fine.
This article also says that T-mobile is expected to get the Captivate, which is false. It already has the Vibrant.
What GPS Problem??
No problems for me, thus far...
Mine has locked once. After that it refuses and just triangulates using cell towers and accurate within 2600 meters.
I'm not sure I would call it a "problem", but the GPS chip in these things is definitely not as good as the GPS chips in most other newly released phones. It could be a software issue, but I doubt it. The Aria would consistently lock onto twice as many satellites as this thing. When driving near large buildings and under bridges I sometimes lose a lock and Google Nav jumps around, which never happens in those same places with the Aria.
It seems to be working fine for me, but then I saw that someone had posted a fix for it when you dialed into the GPS settings, so I did that, and now.... it's still working fine!
gtg465x said:
I'm not sure I would call it a "problem", but the GPS chip in these things is definitely not as good as the GPS chips in most other newly released phones. It could be a software issue, but I doubt it. The Aria would consistently lock onto twice as many satellites as this thing. When driving near large buildings and under bridges I sometimes lose a lock and Google Nav jumps around, which never happens in those same places with the Aria.
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Click to collapse
I've recently used both an Evo and an ATT-band Nexus One. I do have to say that the GPS on both of those seemed to acquire signals from satellites much faster than the Captivate, and give a more accurate location. Even standing outside, in the open, this one never appears to lock in on my precise location as well. I realize that's only anecdotal, but I no longer have access to either of the other devices.
Maybe its just mine, but I traveled over 300 miles today using Google Navigation, the phone up in the dash, with a clear view of the sky keep on having issue finding me.
I have an N1 and Aria, neither of these have these issues.
Do the specs indicate which GPS chip is being used? Some are better than others. Is it SirFStar III, IV, or MTK or what? This can certainly make a difference but costs about the same, so why get a cheapo chip? Hope Samsung did not do that.
GPS is definitely poor. From watching GPS Test I'd wager it's a firmware issue. No reason to have satellites popping in and out of view in the middle of a field on a clear day...
I've had many GPS units (>10) and the GPS in the phone is the second worst I've ever had. Very flaky. It looks like they also tried to mask the problem by averaging a bunch of the last fixes. I say this because the speed indication trails reality by quite a bit!
And I did try the proposed settings elsewhere but it didn't seem to improve much.
Hopefully they'll get this fixed. It's not the way GPS should be working on a top tier phone.
AJerman said:
It seems to be working fine for me, but then I saw that someone had posted a fix for it when you dialed into the GPS settings, so I did that, and now.... it's still working fine!
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Okay, so to change my stance a little, the GPS has been a little off tonight. Locking has been slower than I like, but it has been locking, and I saw it lock to at least 7 satellites earlier so I know it has no issue with handling that many at once.
The bigger annoyance that I'm having now is that my AGPS is off by quite a bit, telling me I'm in the next town over until it gets a full GPS signal. Not only is this annoying, but it also throws off every app that uses the cell data for coarse location, and I wouldn't be surprised if it has an effect on how fast it locks to the actual GPS satellites since it has the wrong location info to start which is the whole point of AGPS.
I actually did the GPS tweaks found in another thread, and I was navigating around my city. Maps was spot on for 98% of the time. Once or twice it put me about 30 meters away, but that was when i was surrounded by trees or concrete. Overall, I was very VERY impressed with the voice navigation, and the re-routing it did when i drove past a turn!
hmose said:
Do the specs indicate which GPS chip is being used? Some are better than others. Is it SirFStar III, IV, or MTK or what? This can certainly make a difference but costs about the same, so why get a cheapo chip? Hope Samsung did not do that.
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Click to collapse
I'm starting to think that the processor and screen on this phone cost so much that Samsung had to cut corners in other areas to keep prices competitive. So far we've seen widespread evidence of crappy chargers (take forever to charge), GPS chips (slow and not very accurate), compasses (all over the place), internal memory (slow memory is causing the stalling issue / lag), and lack of camera flash. Hopefully not all of those are hardware issues and some can be fixed with software, but I'm just saying, they might have cut some corners to keep this thing reasonably priced. Personally, I would have rather paid $100 more to have the best phone ever made hands down. Oh Samsung.
I got it to lock like one time outside. Then I found this http://androidforums.com/samsung-captivate/128026-everyone-who-having-gps-problems.html and now it locks on inside my house. And this is actually GPS I'm talking about not wifi/cell tower triangulation. Hope it helps some of you.
I picked mine up the 19th in the burbs of Chicago. Drove up to Milwaukee with it the same day and did a side by side comparison with my Garmin GPS after my friend sent me the article.
Besides 2 minor hiccups, they worked very similar.
*the first hiccup shouldn't even be credited as a hiccup because it was an alternate route, I knew from experience it was slower but my Garmin and my Magellan of past never recognized it as the faster route.
*the second hiccup was when I was driving down 294 to merge into 94. Both had about the same instruction but out of nowhere my captivate's nav system said to take a left into a random road. It "recalculated" after a quick flicker and went back on course with my Garmin.
Recently I noticed there was an update for the Maps application which gave me "Navigation" and after installing it, I prefer my phone to my Garmin because:
1. It now gives you a picture of the destination in "street view" which you can touch and scroll around when you've arrived or pretty much arrived.
2. It shows traffic (green is good, red is bad)
3. I'm not sure if this was before the update but you can scroll through the map using the touch screen rather than just zooming in and out.
I'll do a few more runs driving between Milwaukee and the Chicago burbs before I completely set aside one or the other, but my experience has definitely met my expectations of a GPS
Why not download GPS NMEA MONITOR App and watch the data sentences. If they keep coming then it is a software problem, not the GPS Chipset. If those data sentences are stopped, then you got a hardware chipset reception problem. Try getting a clear view of the sky.
Zero GPS issues here, faster then backflip, tilt, & tilt2 for me. Grabs and maintains connection just fine.

[GPS] The Unofficial GPS COMPLAINT/NAG/EVIDENCE Thread

Post all your nag/complaints/evidence of GPS problems here.
All investigation works goes here:
http://forum.xda-developers.com/showthread.php?t=789383
I just finished doing a one hour GPS test drive with the new OTA JH7 and guess what!!
The GPS is still unreliable.
I did a 30 minute drive before the JH7 OTA fix and it was terrible. It would lose GPS signal easily. The GPS would rarely get a fix and when it did, it wouldn't refresh for another 20-30 seconds.
With the new JH7 OTA, positioning while stationary is quick. You can get indoor GPS (probably from AGPS). Now, I was using it and I'm starting to believe we will NEVER see a real fix.
My reasons:
The hardware GPS has an accuracy of ~10 meters (~30 feet).
The hardware GPS has slow processing speed.
I believe this "fix" is just software code trying compensate for the poor hardware. It seems to take the bearing and speed to estimate where you will be. This won't work all the time but it gives the illusion of a reliable signal. You can see the device doing this when you make a quick change in speed or direction.
For example:
If you break quickly, the GPS will tend to position you further than your actual position. You might see GPS position "travel backwards" after you do.
If you accelerate quickly, from rest/full stop, the GPS will lag completely. It might lose the signal or not update until it gets a new "position" later (probably an amalgamation of speed, bearing, and [inaccurate] position).
If you make a sharp turn, the GPS will keep traveling that path and then slowly work it's way back to where you are. For example, if you make a 90 degree right turn, you'll see the GPS plots a semi circle arc to your new position.
I currently recorded my data with a custom written application I wrote but I had the logs set to write every 30 seconds and I didn't have a reference GPS unit to compare.
The next time, I'm going to drop it 1 second frequency and run the application on my G1 and Rhodium (TouchPro/Tilt 2).
What are you experiences with this new GPS "fix"?
I completely agree.
I just came into this forum to post the same thing.
I have some terrible My Tracks screenshots to take, but now my Captivate isn't detected when I try to plug it into my computer
This is using Cognition v2.1. The GPS locked very quickly right after flashing, but just tonight, it wouldn't get a lock to save my life. After repeatedly entering the LbsTestMode and changing settings, it went to getting a lock again... but had me ~100 feet off.
I do not think the GPS will ever work as good as any other modern smartphone. The GPS in this device just sucks, and no software will save it.
I agree with pretty much all that you wrote. It is very "laggy" and I too can see it estimate your path. Re-routing also takes very long and sometimes may not be in time.
I tested it with my Garmin side-by-side and there is no doubt the Cappy is worse. I know it's a phone and not a fair comparison with a "real" GPS, but it is a letdown.
FYI, Cognition improves the GPS significantly from my stock version (JP6)
Same here. I would not consider this as a fix for GPS.
The captivate is my first android phone. Im stuck with att so i made the switch from iphone to the captivate because it was thr first phone that was not crippled. I love android. Period. Im never going back. With voodoo and oc this phone beats the crap out of an iphone.
But today is the last day i can return it to best buy. I was waiting for a gps fix/improvement. But it didnt help. So im returning it. Im going to buy my friends aria for $100. Once samsung fixes thr gps i will buy this phone again.
Ps. Android. My new best friend.
is this the first Samsung android phone? Im pretty disappointed. Their other products are top notch
I have the opportunity to swap out my cappy for an HTC Aria phone but it's my last opportunity to exchange it because they're extending my 30 day warranty. I had to talk Wirefly into letting me because of the bad GPS in the phone. They can either give me another Cappy which would be a brand new (but another defective GPS phone no doubt) or they'll just give me the Aria which has a decent working GPS but not anywhere near as nice as the Captivate in every other way.
What would some of you suggest? I'm leaning toward just getting the Aria and maybe upgrading to a better phone later on.
galaxyjeff said:
I have the opportunity to swap out my cappy for an HTC Aria phone but it's my last opportunity to exchange it because they're extending my 30 day warranty. I had to talk Wirefly into letting me because of the bad GPS in the phone. They can either give me another Cappy which would be a brand new (but another defective GPS phone no doubt) or they'll just give me the Aria which has a decent working GPS but not anywhere near as nice as the Captivate in every other way.
What would some of you suggest? I'm leaning toward just getting the Aria and maybe upgrading to a better phone later on.
Click to expand...
Click to collapse
My wife has an Aria, pretty good phone, verry poor battery life. Great GPS lock in 10 sec no matter where are you. Small screen but perfect size for holding.
I would have to disagree. No it's definately not as good as my garmin. However compared to stock...lol.. Its no contest. The Ota update is definately an improvement. It makes it at least usable. Before it would take anywhere from 10 min or more to lock. On several occasions i got half way to home before it would lock. Tonight i tested it and got a lock within 10 secs.
Thats not to say this update is without its issues. You can definately tell there is some anticipation of where you are going by about 10 to 20 feet. However rerouting happens quicker for me than it did before.
There is also the issue of wifi and 3g being on at the same time. Of course ill have to reenable tethering too if possible. Other that that though it is more positive than negative for me. At at least i can bring up bars and restaurants without waiting 20 minutes.
Sent from my SAMSUNG-SGH-I897 using XDA App
kaczu said:
I would have to disagree. No it's definately not as good as my garmin. However compared to stock...lol.. Its no contest. The Ota update is definately an improvement. It makes it at least usable. Before it would take anywhere from 10 min or more to lock. On several occasions i got half way to home before it would lock. Tonight i tested it and got a lock within 10 secs.
Thats not to say this update is without its issues. You can definately tell there is some anticipation of where you are going by about 10 to 20 feet. However rerouting happens quicker for me than it did before.
There is also the issue of wifi and 3g being on at the same time. Of course ill have to reenable tethering too if possible. Other that that though it is more positive than negative for me. At at least i can bring up bars and restaurants without waiting 20 minutes.
Sent from my SAMSUNG-SGH-I897 using XDA App
Click to expand...
Click to collapse
The problem with comparing the Captivate's GPS performance to stock is that stock was just garbage. Almost anything is an improvement from a stock Captivate's GPS.
We need to compare the Captivate's GPS performance to other phones -- the Aria, Droid, iPhone etc. The Captivate's GPS just simply sucks compared to these phones, even after Samsung's "fix".
I wish I could return it, but there are no other decent options with AT&T
I have to disagree also. I just drove from Illinois to Texas and my captivate got me to my destination with only a couple dropped GPS signals. Was a 12 hour drive and it did what it needed to. Just saying this was a "real world" test and it passes in my book.
Dropped w/ my Captivate XDA App
My captivate is every bit as good as my aria was and better than my iphone 3g was. I'll agree its not the best. But this fix is working and if that's the best it can do I'm satisfied. I took a 6 hour trip the other weekend and it did loose signal in cloudy conditions, but when the sky was clear it never steered me wrong it even redirected me quickly, my friends vibrant also got him to where we were meeting. Now with the new firmware it gets a fix in overcast conditions. It may not be perfect but its what we have to live with. And I don't think I'd give up my samoled screen and good graphics processor for a better gps.
Sent from my SAMSUNG-SGH-I897 using Tapatalk
johnyhoffman said:
I have to disagree also. I just drove from Illinois to Texas and my captivate got me to my destination with only a couple dropped GPS signals. Was a 12 hour drive and it did what it needed to. Just saying this was a "real world" test and it passes in my book.
Dropped w/ my Captivate XDA App
Click to expand...
Click to collapse
It boils down to how much you expect the GPS to work.
If you expect it to work with a few dropped signals, a few random wanders, but still generally get you to your destination -- then it is OK.
If you expect it to work as good as other modern phones, it sucks.
phr00t said:
The problem with comparing the Captivate's GPS performance to stock is that stock was just garbage. Almost anything is an improvement from a stock Captivate's GPS.
We need to compare the Captivate's GPS performance to other phones -- the Aria, Droid, iPhone etc. The Captivate's GPS just simply sucks compared to these phones, even after Samsung's "fix".
I wish I could return it, but there are no other decent options with AT&T
Click to expand...
Click to collapse
try the Sony Xperia 10a. I have one and it's a nice phone. Lot's going on in that forum also. GPS works nicely and it's an 8Mb phone. Only A-droid 1.6 w/2.1 coming.
Unfortunate for me, I had a deal with AT&T to sell 50 of these devices ($15,000 down payment) with a custom app I wrote for this company. It's not going to happen now because the GPS is borked. Highway driving is one thing, but in the city, where you would be making turns left and right, it's counter productive. The GPS will be misleading you.
My project hasn't completely fallen through, but I would have to resort to the much smaller HTC Aria. I would say the Sony Ericsson Xperia X10 but their OS is a joke. It runs 1.6 and has no Exchange support. SE said they'll make 2.1 (seriously!?) available end of october (meaning November). By then Gingerbread (2.5 or 3.0) will be out.
I just don't want to return this Captivate I got for free to develop the application...
Yea here's mine... Thx samsung, GREAT FIX!
Sent from my SAMSUNG-SGH-I897 using XDA App
CLShortFuse said:
The GPS is still unreliable.
...
What are you experiences with this new GPS "fix"?
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Click to collapse
I've gotten what I would call good performance from the GPS today, but I only use it for driving and I probably don't need better than 10m precision. Prior to updating today to JH7, my phone would take 3-5 minutes for an initial lock (which usually required prepping with the Ulysse Gizmos' GPS app), after which it would stay relatively on-point. Today, post-JH7, my phone gets a spot-on lock with 5+ satellites within 10-15 seconds.
Pre-JH7, Google Navigation would trail my actual position slightly, as determined by the very unscientific method of glancing over at the phone while driving and noting that I would be passing a street intersection and Google Nav would still have that street roughly 10-20 feet forward of my position.
Post-JH7, again very unscientifically, the map would have me passing intersections at the exact moment I was actually passing through those intersections. Your comment about it estimating your next position rings a bell, but I could just be "remembering" a non-existent hiccup during one of my rides. Of course, I could also have missed a few dozen hiccups, because I was keeping my eyes on the road. =)
I live in the 'burbs north of NYC and, although I have no immediate plans to head into Manhattan, I will install MyTracks tomorrow and do some more testing along curvy suburban roads with and without extensive tree cover (I'd also be happy to use your custom application, if those logs would be more helpful to you).
Can you give me some specific ideas of what scenarios would help you get more useful test data? Things like:
1) Proceed straight at 30mph. Take 90 degree right turn at 20mph. Expectation would be that MyTracks would continue straight for at least a few feet before correcting itself.
2) Proceed straight at 30mph. Come to abrupt and complete stop. Expectation would match above.
I have a GPS in my car and use it for road trips. The Captivate GPS works well NOW for what I want to use it for, location based services like gowalla and such. It also works well for me using Google Nav's Walking feature.
The update is definitely an improvement for me. Before the update, unless I had wireless network assist turned on, my GPS would NOT get a lock. Now it does in under 20 seconds.
I too just joined the android community after having an iphone for 3+ years now... captivate being the first powerful hardware based phone that i saw (and that ATT had).I'm probably never going back to the iphone even if i never get gps working cause it is still so much better imho.
But the only thing that makes this so dang frustrating is the fact that... was there ANY product testing!?. I mean i can understand if it was a bad "batch" of phones that made it out. Or even if gps was "subpar", and had an OCCASIONAL incident of what we are experiencing (Like once every 15-20 min, then would reset and work fine). But the fact that it has not worked since product launch on EVERY phone (captivate, fascinate, vibrant, epic 4g, i9000) Even the ones that claim to unaffected still have accuracy/lag issues. I mean how did this get past field testing? I just hate the negligence .
I mean atleast the iphone 4 reception issue was only conditional to how you were holding the device. But no one GPS has correctly worked -_- just frustrating
I agree with this thread so far. It's insanely frustrating.

my GPS testing: OK for me. My opinion...

I bought my first Captivate at the very beginning of August. I wanted the GPS to work, so I could use it instead of a separate GPS unit sometimes. After about 5 days the GPS was really struggling to lock. I put it outside under the open sky for 5 minutes with GPS Test, and it saw lots of satellites but used zero. I reset the phone and poof, it worked properly again. That seemed like a strange bug to me. I heard an update was coming by the end of September, but that was going to be outside my 30 days, so I returned my Captivate to Best Buy and got my $230 back, no problems.
Sept 7, I bought a new Captivate, now only $150 at Best Buy. This one worked fine and the GPS never completely failed like the first one did. But I didn't test much as I waited for the update. September 22 I forced the update on my normal unrooted captivate, and it went fine. I did some testing and the GPS seemed to track OK and lock in a reasonable time. Now its a week later and it still seems good.
Here are a couple comments.
First a note on my GPS experience. I own 3 GPS units besides the Captivate, and older MIO C230, a Garmin eTrex Centure HC, and SPOT 2 GPS Messenger. I also have extensive experience with a Garmin Nuvi 1390T. I ride a dirt bike in the desert and have used tracks to navigate extensively.
- Time to get satellite lock. The Captivate does often take a while to lock on the satellites. But so do all my other GPS devices. Sometimes they lock quickly, but often they can take a minute or more. This is related to whether they have stored data on where they are, and thus know where to look for the satellites. At any rate I don't always get a quick lock on the Captivate, but it has never failed to get a lock under a clear sky if I give it up a minute or two. 10m resolution is typical once locked under a unobstructed sky. For those having trouble with this: Are you giving the Captivate a clear view of the sky and a couple minutes? Yes, sometimes GPS's lock indoors and really quickly. But in my experience this isn't always true. What I'm saying is the Captivate works similarly to the other GPS's I use. Sometimes fast, sometimes slow. But it is always locking under a clear unobstructed sky within a couple minutes.
- Google maps. After it locks, the captivate shows my location on the map well. As I said above, sometimes lock takes a minute or more. And it requires a clear view of the sky most of the time.
- Track quality. I tested with "My Tracks". I run around town on a scooter every day, so its easy to turn on the tracker and and see what happens. I put the Captivate in my pocket on my thigh, back side facing the sky. The only thing obscuring its view is my body. Basically, it seems to work fine. It certainly works as well as my Garmin eTrex. The eTex tracks are always a bit rough too. Yes, the Captivate track does sometimes cut the corner or the curve and is off the street that I actually rode on. But it basically follows my route well. It has always followed me when I loop around a block, or drive down a short dead end and come back. I can definitely tell where I went and what roads I took when I look at the track. I'm not bothered if it shows me 20-40 feet off the road on occasion (as I have noted, so does my Garmin eTrex). I expect this with a 10m resolution.
- Navigation. I've been using the google Navigation app on drives in the car. I mount the Captivate in a mount on the dash, so it has a clear view of the sky through the glass. It's not on the seat, or in the ashtray or in a cup holder. It's mounted to the windshield close to the front, so it has a good view of a broad expanse of sky. This is exactly how I mount the Mio GPS or Garmin etrex or Garmin Nuvi when I use those in the car. Used like this, my Captivate navigation has been excellent. Frankly, its far better app than the Mio or Garmin Nuvi 1390T that I have used. The searches are quick and I like the presentation. Obviously, in Navigation the app knows to lock you on the street. And when I drive past an indicated turn it always notices immediately.
Summary: So I don't know what has changed since my first Captivate, but this one seems fine to me. I don't know if it's the hardware, or the SW update. But so far mine works as well as the other GPS devices I have used. If it keeps working like this for another week, I'm definitely keeping it. I'm sure some have trouble, as I did with my first Captivate. And I do think some others expect too much: I don't expect the Captivate to be "THE BEST GPS" I have ever seen. I expect it to lock within 2 minutes, work for navigation in my car, to find me on a google map and to record a track of where I went. This all seems to be working for me. (And usually it locks in well under a minute for me). I think I'll keep it... if this performance keeps up.
IMO, YMMV
Carl
vintagephone/Carl. Yours is a very useful write up. I use a Garmin GPS for Geocaching, some street navigation and bicycle riding in the country. What you wrote should be very helpful to someone not so familiar with GPS devices in general. Thanks.
= Ron
I completely agree. People looking at 'my tracks' and showing that there are some slight variations - we don't even know if the google maps is 100% accurate, as I know there are certain places where it doesn't match up directly with the road. I think as long as no errors are being presented during navigation (mine is doing fine in navigation mode) there is not really any complaining that can be done. Even my built in car GPS makes a mistakes once in a blue moon.
I'm not sure what Garmin Nuvi you're using, but I have a 2 yr old 250W and it smokes this phone. The phone has me driving through people's yards and buildings. It has gotten better since the JH7 update, its almost what I would call usable now. Try doing a Mytracks track on it, its a joke how far off it is. Its certainly unusable for that.
derek4484 said:
I'm not sure what Garmin Nuvi you're using, but I have a 2 yr old 250W and it smokes this phone. .
Click to expand...
Click to collapse
I'm very familiar with the Garmin I used, a Nuvi 1390T. Negatives for the Garmin included horrible traffic reports, and searches for my destination took forever. Basic Navigation was OK, if you knew the address of where you were going. And if you were going someplace more than 30 miles away (a common undertaking in the LA basin), you just couldn't get there. Searches on the Nuvi only include locations within 30 miles. Frankly, the search was much worse than on my old Mio. I had the Nuvi 1390 for a couple weeks and returned i just as I got my second Captivate. For basic GPS navigation, the Nuvi was OK, but I saw no advantage over the Captivate. Are you mounting your Captivate in the same way and place you are mounting your Nuvi? I actually use a modified Nuvi windshield mount with my Captivate, so my mounting is literally identical.
Now, you Captivate my not work as well as mine. My original Captivate was worse than this one. As I said, YMMV (your mileage may vary).
I use a Garmin V GPS receiver for Geocaching and some other activities which demands a very high degree of accuracy. This receiver will use as many birds as it can find (seldom less than five) to determine its location but a cell phone GPS receiver may limit the number of satellites it tracks to conserve battery power.
Using four satellites, the accuracy of the Garmin V typically comes down to a target area that is two to twenty feet in diameter. This unit is fast; I can watch the current location triangle move past streets just as I am able to make out the street signs.
The Captivate I ordered will not be here until later today so I can't report anything about my experience with that device. I have been using an HTC device (AT&T "Tilt") and Google Maps for several years now and can report it has very good GPS accuracy and speed when compared to the Garmin unit. I would be pleased indeed if the Captivate even comes close to the performance of the Tilt.
As with any GPS device, it has to have line of sight visibility with at least three satellites to report its position with any reliability. Clouds (with heavy moisture), trees and tall buildings can reduce GPS accuracy substantially. Bicycling through heavily forested areas reduces the accuracy of my Garmin V from a few feet to hundreds of feet. As it takes a few minutes for the receiver to "lock on" and recalculate its position, after pedaling through a forested area I can be a mile up the road before the display catches up. Even at bicycle speeds (15MPH) I have missed turns simply because of trees!
With the Tilt, moving on foot around tall buildings, Google Maps sometimes can't figure out where I am. In the car, I usually pull the sunroof shade back so the Tilt gets a clear shot at the sky.
One final point: If I have the Garmin running at home, shut it off, then restart it again when I am fifty miles from home, it takes maybe five minutes to find three in-view birds. There is a feature in the Gamin that allows me to move its cursor to about where I think I am and it, then it uses this information to find new birds. I use this feature frequently and it usually saves two or three minutes locking on to a new set of birds. That feature is not available with the Tilt and it can take a full five minutes for it to find three birds when I change location with the GPS receiver turned off.
I hope these comments are useful. A cell phone with GPS capabilities is understandably no match for a single-purpose GPS receiver and particularly so when the two devices sell for about the same price.
I doubt that it is Maps or myTracks that is off (although I had wondered about this as well) because when you run the Captivate side-by-side with an N1, the N1's lock and track are very fast (almost instantaneous) and flawless. Of course we all know the Captivate's lock and track issues. The N1's track would not be so perfect if it were an issue with the base map accuracy, when the app on both phones is the same and accesses the same data.
The issue can also be seen running GPS Status or GPS Test together too, the N1's lock is always better, although I see no appreciable difference in SNR values for each satellite. It is just like the Captivate simply will not lock, even when it sees the same satellites. That is why I am sure it is the driver issue and therefore fixable.
Sent from my SAMSUNG-SGH-I897 using XDA App

[Q] Is my GPS chip defective ?

Hello,
I'm encountering some issues with my Samsung Nexus S GPS. I got the i9023 (Europe/SLCD) version of the phone, which is running default rom (stock), freshly updated to 2.3.4 (via official OTA!).
I couldn't figure why, when using Maps, my position would usually be around 1 km away from where I am. I found out later, this time using Navigation, that it is desperately searching for a GPS signal, that it can't find. Sometimes I manage to get a lock, when I keep it running for like 30 - 40 mins, but it immediately disappears. GPS Statuts keeps showing 0/5 sats.
I was convinced that my GPS chip was defective.
But today, I was hanging out in the city and tried running Navigation. I got a lock, for the first time, within a 15 sec delay. That was the first time that I managed to get live GPS tracking. I've walked a bit around, and the tracking was really, really accurate.
Back home, in my apartment, again I can't get any signal. I live in the 3rd floor, walls aren't that thick and, as for an anecdote, in the same room, my iPhone 3Gs instantly finds my position.
I've bought this phone 6 days ago and therefore still under warranty. Question is, can we say my GPS chip is defective ? Is it worth requesting a replacement ?
Thanks !
1st) You cannot expect to get gps reception inside even with professional equipment. When your iPhone gets a fast fix it's most likely WLAN triangulation. As Apple uses a different database than Google, it may work on on your iPhone and not on your Nexus for a paticular place and vice versa.
2nd) It's unlikely that your gps is broken if you can connect to GSM/UMTS/CDMA2000 networks as gps is processed using the same chipset.
3rd) That 1km-off-fix might be celltower based location, 1km sounds quite plausible.
4th) Try _NOT_ to move until you get GPS fix.
5th) Keep internet access while trying to get a fix. The Nexus S as most phones on the market use assisted gps, where your phone contacts a server that provides data which enables your phone to track its position more easily.
6th) Good luck.
Yes, well, I had 2 friends which came to my place, in my room, and just activated GPS on their iphones and it located them straight away, to our exact position. So it was definitely the GPS tracking and not triangulation.
Indeed, when MY phone locates me off 1 km, this is definitely triangulation or cell-towers.
Of course, when I try to get a fix in my apartment or on my balcony, I just put it on a table and must wait for at least 30 mins to get a lock, and it disappears quickly. Doesn't seem normal to me ...
Finally to answer your 5th point, I got 3G, so a perfect fast & smooth inet connection.
GPS testing should always be done outside, you are not supposed to use it indoors.
What is probably happening there is that the other devices are more sensitive and can still get a lock. You might be able to get a lock if you place your phone very close to the window.
I got a Nexus S recently and noticed that the GPS is quite weaker than the one on my old HTC.
Although the Nexus is faster to get a lock (if you let it use 3G) the GPS itself is less sensitive and accurate.
It looses signal easier, for instance, if i go under some trees, and it takes more time to get signal back after loosing it, for example, if you go under a bridge, the old HTC would get the lock back in 2 seconds after leaving the bridge, the Nexus took half a minute.
Having said that, i think it's good enough for driving navigation, i have done some tests and on the road it behaves well enough.
You shouldn't be surprised, this phone is very similar to the Galaxy S and that had terrible GPS issues, this nexus is better, but still weak.
Thank you for your feedback, temp9300 !
I guess the Nexus S can't compete with iphone's. But it's ok, as long as it works fine outdoors, this is what matters.

GPS Observations

Just my observations, take it for what it is.
We all know that GPS is hit or miss on these phones. Many people have exchanged their older build phones for newer builds and have exalted the GPS function as incredible. Coming into the last few weeks before my one year goes by I wanted to do some testing on my 1007 build. I've been lucky so far, GPS works for me.
I have tried all the newer built roms for both Froyo and Gingerbread. While I did see a little improvement in the lock times I do believe this is minimal. I went back to stock yesterday, KB1. A friend wanted me to go on a drive about an hour and a half away so I thought this would be a good chance to actually test the GPS function where I could give it my full on attention.
What I found:
Lock times w/ supl.google.com, port 7276 - bad as always
Lock times w/ h-slp.mnc410.mcc310.pub.3gpnetw, port 7275 - better
Lock times w/ either and gpsjm9.zip - 10 - 15 seconds with 10 - 15m lock initially, 8 - 11 satellites used
Not so interesting so far...but I did find when I removed my Body Glove case the SNRs, using GPS Test by Chartcross or LBSTestMode, for all the satellites increased slightly. I thought that was strange but what I saw next was stranger. If I held the phone with my hand covering the top half of the back of phone, the area where the antennas make contact with the battery cover, the signals would go away. Not completely, it would still show however many satellites it had locked before place my hand in this position but all the SNRs would drop by half or more and the satellites would show as not being used.
I removed the battery cover and repeated, same results.
Tried this with Maps, Navigation, My Tracks anything that would have to use this signal. When blocked, I would get the searching for signal status bar icon but a few seconds after removing the block it would come right back.
I was thinking it may be interesting to go to my local AT&T store to show this in action. Not sure if I would accept a refurbished phone or even a new one as the GPS will work if I hold it or place it in a holder so the antennas aren't covered. I do love my 1007 build and it's only another 53 weeks until my upgrade.
I traded two 1008 build phones with horrible gps in both. I got back a 1008 and an 1102 and both of them work very well now. It is honestly like night and day difference for me. Doesn't matter if I am on stock software or custom roms. Right now I have mosaic v and can get 11 locks and it never once lost tracking. Seems pretty rock solid for me far. I do think the 1008 build I have is better than the 1102.
thats the same configuration I am using, have you tried this fix?
http://www.darkyrom.com/community/index.php?threads/guide-gps-quickest-fix-solution.2022/
Sent from my SAMSUNG-SGH-I897 using XDA App
Just to further muddy the waters.
My phone is rooted 2.2, but other than that stock. I exchanged my original phone for the shut down problem (hoping to get a better GPS, actually). Build number is worn. Might be 1007.
Internal GPS works OK, but not nearly as good as my tiny Bluetooth dongle GPS. I have the extended battery with the plastic door so the little contacts inside the battery compartment don't touch metal. Didn't really notice much GPS difference from stock battery and metal back.
When outside by my pool I get a certain level of SNR with the Chartcross GPStest, say about 38 +/- on a clear summer night in north Texas. When I set the phone down on a metal mesh poolside table the SNR jumps up about 2-3 ticks, say 40 to 41 for the best satellites, well into the green.
Acquisition times seem better on the table too, less than 10s. Ground plane I guess for the antenna? All my antenna theory has faded over the last 35 years of disuse.
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Tested tonight with original battery and metal back on the same metal mesh table. Similar results.
To add another anecdote.
Originally got a 1007 build phone in August 2010. GPS under eclair was marginal. Didn't get better under froyo (cognition flavors). Exchanged the phone at an ATT service center. The unit received was a refurb 1010 build.
GPS on this unit so far has been about 98% as good as my Garmin.
It came with Froyo, but only had that long enough to get home and put Cognition 5 beta x on it. First fix is Fast, Tracks well. notices that I didn't follow directions, quickly.
Even played with it the other day with Google Earth zoomed way in. It literally was tracking where I was walking.
I do believe the Captivates are random with reference to GPS, especially the early builds.
Stop pulling your hair out over this issue. Exchange it for a refurbishment unit that is fixed and make sure you test it while at the device center.
Dont be scared of a refurbished phone. Trust me it will come in better condition cosmetically then the one you probably have.

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