GPS Flawless/I am requesting XDA Community and Developers to please read!!

danquirk2000

Member
Aug 21, 2010
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I just recently received a new Captivate today through the ATT insurance program that came preloaded with the JH7 Eclair build. The first feature that I was anxious about testing was the GPS since myself and others on this forum seemed to experience difficulty applying the OTA update from ATT. I drove an estimated 20 miles in the city and 15 miles on highway and noticed that I no longer experienced lag when making turns, or when I came to a complete stop and the navigation icon never jumped to adjacent streets or went over a 10m accuracy. I also was able to get a lock in 3-5 seconds while going 70MPH during my highway drive. When I returned home I rooted my phone and made a Nandroid backup and proceeded to flash cognition 2.4.1. Once I did this I decided to test the GPS again with a custom ROM installed and noticed that the GPS issues that I had previously experienced with my old phone were present once again. So after I tested the GPS on Cognition, I decided to restore to my original firmware and the GPS accuracy was restored to the favorable results as previously mentioned. What I am asking the community as well as the devlopers at XDA is if I provide you with my Nandroid backup files, would this be helpful in solving the GPS issues once and for all? I am just uncertain if maybe newer phones that came preloaded with JH7 may have different GPS settings than the OTA updates.

If the developers would like my Nandroid backup please just ask and I will upload.

UPDATE*

Here is the image file of the stock JH7 that has given me VERY accurate GPS results from the previous stated post. This is from a Nandroid backup and I do not know how you would go about installing this but I'm sure someone from here does and will test it. This has not been tested yet, but I respectfully challenge the developers and community to try this out to see if it is an improvement. This is an Eclair JH7 rom. Thank you for your time.

http://www.filefront.com/17508797/system.img/
http://www.sendspace.com/file/ryxaw1

UPDATE 2**

I went on about a 30 minute trip and here are my results

http://maps.google.com/maps/ms?ie=UTF8&hl=en&msa=0&msid=114887993519189258855.000494f37559dc102964c&t=h&z=12

** Please note you will need to zoom in to notice all of the turns that I made. I also made a U-turn and traveled on some of the same roads in opposite directions. Everything is just as accurate as the day before.

UPDATE 3***

I would like to extend my thanks to mattbeau for trying this out and posting his results. The results furthermore prove my hypothesis and are consistent with my results. I requested mattbeau to post detailed instructions on how to flash it so others can try. Please I encourage others to give this a try the more tests we gather the easier it will be for the Developers to find what makes this different.

mattbeau My Tracks: http://maps.google.com/maps/ms?msa=0&msid=208605913791985313826.000494f74ae16f5e33c81

UPDATE 4****

Very special thank to mattbeau for posting instructions on how to get this to work. Still need a few more people to test this but so far this is the most accurate the GPS has ever been on the Captivate here it is:

download the following: http://www.multiupload.com/CB5PFRTRYF

extract with winrar or what ever you want

so this is what is working for me.
ensure the clockwork update.zip is insalled on the root of your internal SD card
create a folder /sdcard/clockworkmod/backup/jh7gps/
copy system.img and nandroid.md5 to the above folder
Oneclick back to JF6
enable debugging under settings
using adb
adb restart recovery
select reinstall packages
(it will install teh clockwork recovery)
again select reinstall packages
select advanced restore
select jh7gps
select restore system
select yes
your phone will reboot with the new system.img installed

baseband is still jf6

If I could as that everyone that tries this please post their results. The more consistent this is the more things we can rule out.

UPDATE 5*****

I apologize that the megauploads links it temporarily unavailable. We are currently working on getting this back up as soon as possible. Also will be posting my My Tracks for day 3 shortly as well. I encourage anyone else to post their results as well.

Here is mattbeau's link that was originally on megauploads. Since some of you were having problems I moved it to here:
http://www.multiupload.com/CB5PFRTRYF

Let me know how this works out. I thank all of you for your assistance.

UPDATE 6******

Here is the My Tracks for the third day of testing. GPS accuracy does not appear to be deteriorating and have consistent results from previous tracks. This is looking more and more promising by the day. Comments are welcome!

http://maps.google.com/maps/ms?ie=UTF8&hl=en&msa=0&msid=114887993519189258855.00049509766fdff4bcb11&ll=34.720186,-77.346539&spn=0.005176,0.013078&t=h&z=17

Thank you mattbeau for your thorough comparison to other JH7 ROMs. Please keep us all posted on your findings.
 
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fatttire

Senior Member
Oct 11, 2010
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Some people think that 2.4 caused GPS issues that were worse than stock. I'm not necessarily saying where I stand on the issue - but your decreased performance may just help prove that 2.4 is bad at GPS.

I feel skeptical that Samsung would have a different OTA JH7 and in store JH7 and what I said above sounds like a better idea. Hmm maybe I should go to an earlier version.... helpful either way!

Sent from my SAMSUNG-SGH-I897 using XDA App
 

danquirk2000

Member
Aug 21, 2010
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I am definitely not certain as well, but the GPS performance that I am experiencing with this new phone is up to par with my Garmin. More notably, I have had my old captivate since early August and have tried out all official updates on it including JH7 that don't even compare to the perfect performance this one has. I am just trying to see if I could give my Nandroid backup to someone that knows more than I do and possibly solve this issue for custom rom development etc...
 

zippox180

Senior Member
Aug 30, 2010
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im not sure about this although there quite possibly could be a combination of hardware and software. my wifes phone works perfectly with gps and we got ours at the same time but my gps has been horrible since day one but we use hers and no lag, jumping off the roads or anything
 

di11igaf

Inactive Recognized Developer
Sep 6, 2010
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East Coast
ive had 4 captivates so far. me and my wifes original 2 and 2 replacements. all 4 have been the same where sometimes there dead on accurate, and they might be like this for a week. then one day they might take 10 min. to get a lock where the day before it would lock instantly. overall id say the gps on all the phones ive had werent horrible, but could be better. im to the point now that i think its just a hardware issue, and no matter what settings we put in or what we change, the gps just isnt going to be perfect.
 

fatttire

Senior Member
Oct 11, 2010
528
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I am definitely not certain as well, but the GPS performance that I am experiencing with this new phone is up to par with my Garmin. More notably, I have had my old captivate since early August and have tried out all official updates on it including JH7 that don't even compare to the perfect performance this one has. I am just trying to see if I could give my Nandroid backup to someone that knows more than I do and possibly solve this issue for custom rom development etc...

I had that kind of perfect GPS with my captivate once and lost it.... once you have it never let go :) hahaha

Sent from my SAMSUNG-SGH-I897 using XDA App
 

danquirk2000

Member
Aug 21, 2010
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I will continue to track all my trips for the next couple weeks and post my results. I also have made a nandroid backup of the stock JH7 firmware that came with my phone that I will post shortly.
 

boomerod

Senior Member
Sep 8, 2010
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Dallas, TX
OP, so many of us are so over this GPS issue with these otherwise very nice performing phones. It's just a damn shame that Samsung let this line go to market with this type of problem. That being said, I, for one, appreciate those that continue to try to find a way to resolve this issue. I am one of those that read CLShortfuse's complete write-up on this matter and form that I feel pretty certain it is NOT a hardware issue; the same chip is used in other devices without issue. I think that the issue is with Samsung's coding and, perhaps, the placement of the chip in the phone.

I see a lot of notes about quick locks, slow locks, etc....the real issue is tracking, not locking. I have found that even my Garmin can take over a minute to lock, depending on where I am in the city (elevation, hills, etc.) and also is sometimes affected by weather. I've waited over 5 minutes for my Garmin to lock (only a few times) but when it does it stays locked and my tracking is very good. However, even my Garmin will loose me for a few seconds, especially when taking a ramp that it didn't expect me to (not the route it planned for me). Unfortunately, neither of my 2 Captivates worked this way. It's perplexing and frustrating. I can tell you that the fastest locks I ever got were immediately following the OTA update (I got mine through Kies Mini). Unfortunately, I flashed another ROM before I tested the tracking.

I hope some devs out there will take your offer seriously and take apart your backup, if possible.
 

fatttire

Senior Member
Oct 11, 2010
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I agree with boomerod - remember the biggest problem for us is the losing a lock part mid-trip

Sent from my SAMSUNG-SGH-I897 using XDA App
 

TheSopranos16

Senior Member
Dec 2, 2008
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Marlboro, NJ
I would think the first step would be to have someone with gps issues flash your nandroid. If that makes their gps perfect as you report, then it may be worth investigating further... just my .02

Sent from my GT-I9000 using XDA App
 

buddy17

Senior Member
Aug 9, 2010
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are you kidding me??? zoom in on that track map, and you will see it takes you off the road all over the place. Accuracy is still horrible. I have never ever seen a phone go off track like that so dont tell us to "live with it". It may look good zoomed out but try actually looking closely at that and tell us it is perfect
 

danquirk2000

Member
Aug 21, 2010
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Well buddy17, if you do look closely at that map you will notice that it is off less than 5 meters for the short period of time that it was off. Most GPS software maps auto lock onto streets when they are that close but when using My Tracks it does not. I am almost certain it is impossible to have GPS that is spot on all the time and this could also be due to the inaccuracy of Google My Tracks. If you would post your results I am sure you would see a significant difference in tracking.

Also the GPS performance on this firmware seems to not have the "turn lag" or movement while being stopped issues that I have previously experienced as well as what others have reported. I am almost done uploading and all I am respectfully requesting from the community is to try it out and see what happens please. I would like to thank the community for their time and effort to make our captivate have the best experience possible.
 
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denellum

Senior Member
Aug 14, 2010
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Dallas
www.denellum.com
Another useless thread of gps nonsense...lol. I cant believe I even looked. Shame on me

Sent from my Ilikeboobs897
I think more or less the shame is on you for posting.

On a side note:

OP I just got a new one today too from the warranty dept. The GPS While driving is nothing but flawless. Thank you for reporting this to us, and I am a 2nd to agree how amazing the mid drive is. Showed me on the road i was on the entire time. And didn't loose a lock.
 

danquirk2000

Member
Aug 21, 2010
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UPDATE**

Here is the image file of the stock JH7 that has given me VERY accurate GPS results from the previous stated post. This is from a Nandroid backup and I do not know how you would go about installing this but I'm sure someone from here does and will test it. This has not been tested yet, but I respectfully challenge the developers and community to try this out to see if it is an improvement. This is an Eclair JH7 rom. Thank you for your time.

Update links are on first post
 

alphadog00

Senior Member
Jun 29, 2010
1,474
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I agree with the others, this thread is a waste of time. Your software image is no different then the other 500,000 JH7 phones leaving the factory or that had the update. If Samsung made a fix, we would see a different version number.

They don't just replace files and leave the version numbers the same - that would be a support nightmare.

If someone was interested, they would just compare your files to another set and look for differences; BUT, because everyone else knows that files don't get changed without creating a new build, they are not going to spend time on your challenge.