CORRECT Hardware GPS Fix

Did the hardware fix work for you?


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chuimk

Member
Oct 9, 2010
39
11
The answer is yes, if you odin back to stock and the type *2767*3855# in the dialer you'll be fine with the warranty. That's what I did before I sent my vibrant in and there were no warranty issues. The trick in the dialer will format the internal sd card and erase any evidence of unofficial updating.

Thanks Mo! :)

I'll just have to research a bit about that odin thing... I already read about it many times, but as I did all my updates using ROM Manager, I never cared. :)

And, BTW, getting back to stock, it seems, will be the easiest part. I just called T-Mobile support to complain about the GPS issue, and the answer was: yeah, you know, there's this new Froyo update that was just released. You should try that...". So, who did you called in your case? Was it Samsung support directly?
 

Mannymal

Senior Member
Nov 26, 2010
314
36
LOL. Mannymal, not that I am counting, but I think this is the third time you have said that you think this is the best it is going to get.

I am waiting until next month when you decide to open it again and replace the solder with MHF4 connectors :p

Perfection can always be improved upon :)
As soon as you post instructions on a MHF4 mod, I'll be the first to try it out. If I wreck my phone then maybe I can beg XDA for another one to try and get GPS perfect for.

A little back drop into my GPS obsession: I am a pilot, and more than once GPS has saved my life when radio navigation has failed me in central america. Even though its just a phone I can't just rest easy knowing that one of my navigation tools is faltering. I practically owe my life to a Garmin 486 .
 

DocMarc73

Senior Member
Dec 26, 2010
372
56
Back to the antenna contacts: what about the other tiny metal contact (the small silver block) right below the copper one?
Is it necessary to have firm contact as well? If yes, how could you improve that? Because you cant bend it anyway ... Would it help to put some metal part on top of it, or do you think that could mess it up?
 

MoWeb

Senior Member
Aug 6, 2010
321
199
3rd Rock From The Sun
Thanks Mo! :)

I'll just have to research a bit about that odin thing... I already read about it many times, but as I did all my updates using ROM Manager, I never cared. :)

And, BTW, getting back to stock, it seems, will be the easiest part. I just called T-Mobile support to complain about the GPS issue, and the answer was: yeah, you know, there's this new Froyo update that was just released. You should try that...". So, who did you called in your case? Was it Samsung support directly?

I called Samsung about my GPS because I got my Vibrant from ebay. They didn't fix anything, all they did was "RESET" the phone. Could have done that myself. Good luck.
 

joeuser

Senior Member
Apr 9, 2007
60
11
turnaround

havent tried the hw fix yet since my gps is fairly good already (new phone, signal strengths averaging 34 outside, accuracy 10m). what i did notice though (like some others), is quite an improvement when i turn the phone upside down. signals average around 41 then and accuracy is always at 5m.

i am very keen on getting the most accurate track recording performance possible on my trips without the need of carrying another device plus charger. so i was wondering if someone thought about a hw mod to actually move the gps antenna to a different place or wire something external? outdoor users will probably have one of those 3000mAh batteries with bigger cases anyway, so there could be some room for experiments.

greetings,
joe.
 

T313C0mun1s7

Senior Member
Nov 24, 2010
422
73
Lake Havasu City, AZ
havent tried the hw fix yet since my gps is fairly good already (new phone, signal strengths averaging 34 outside, accuracy 10m). what i did notice though (like some others), is quite an improvement when i turn the phone upside down. signals average around 41 then and accuracy is always at 5m.

i am very keen on getting the most accurate track recording performance possible on my trips without the need of carrying another device plus charger. so i was wondering if someone thought about a hw mod to actually move the gps antenna to a different place or wire something external? outdoor users will probably have one of those 3000mAh batteries with bigger cases anyway, so there could be some room for experiments.

greetings,
joe.

Ok, Joe. Here is how:

Follow this schematic for assistance:
Maybe you can get Red Green to bring the duct tape and assist, I think he is at the lodge.
circuit_diagram.png
 
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Kingfanpaul

Member
Jul 4, 2010
16
0
First of all I would like that thank you for finally giving me a working GPS. I have tried many different things, apps, roms and this is the only one that worked. BUT with wifi off the best accuracy I can get is within 1700 meters. Anyone know whats up with that? Did I not bend the contact up enough? I just barely moved it up because I was nervous about breaking it. Could it also be that the 3G connection is not very good and sometimes nonexistent here?
 

ZX3ZX4

Senior Member
Aug 13, 2010
106
2
Ok, Joe. Here is how:

Follow this schematic for assistance:
Maybe you can get Red Green to bring the duct tape and assist, I think he is at the lodge.
circuit_diagram.png

T313C0mun1s7-
Thank you so much! I haven't seen anything clearer since the Pentagon revealed its diagram for the path to victory in Afghanistan...
 

Janis

Senior Member
Jul 26, 2006
746
37
Minneapolis, MN US
Wasting a post, maybe

Three days ago, it took me minimally 3 minutes to get a lock, ever. I was one of those stuck with grey bars in GPS Test. I now get a lock on the first floor of the house, completely obstructed, really, in about 20 seconds, usually.

I did read the whole thread. A couple of things:

This didn't seem to help drift, or rather, I've always had wifi on with it, so when I was at least trying to use GPS I was mostly getting wifi locating, which was amazingly accurate. (I live in the sticks, all the way out on the outer edge of the first ring of suburbs). Without wifi on, I can always get a read within about 500 feet, which gets corrected fairly quickly. But thanks to this rigamarole I know that now.

I also know that not a lot of apps (any 3rd party?) don't tap into wifi locating. I would love to see some developers get into the GMaps API, or pick apart Maps to see how that's done. My Maps was always dead on with Wifi. Like, six feet.

I do have fingernails like the "dude" in the video (a couple of them, anyway), and I still had to use the pry tool I got a PPCTechs years ago. I've used it for 100 other things, too. It's cheap, considering the mileage and it'll fit in your toolbox. It really is just a wedge of plastic, but the hardness is such that it does the job without banging up your gadget.

IF $15 is too much, it's a wee softer than Lego. I had actually contemplated trying my DD's Polly Pocket Cinderella's spare leg (#1 Cindy lost it, we interred her, we found the leg. Now the new Cindy has a spare just in case.) Checking out the local second hand store for plastic wedgie toys might prove helpful if you can't get a purposed tool locally. A really nice plastic flatware knife might work, too, but not the regular, cheap, and toxic polystyrene ones (Google that). My other thought was bamboo if it's cut right. It just has to be pretty sharp to get into the .1 mm crack.

Many of us here would be SOL on GPS if it wasn't for XDA. If you're that happy, and if you can (e.g. you're not eating donated food), consider supporting the site. No one's paying me to say it. This site is a tribute to open source if there ever was one. Those of us for whom this worked just reaped the fruits of lots of labor and bandwidth. I love this site for exactly this thread, and 1000's of others just like it.
 
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candyman123

Member
May 9, 2007
43
0
holy moly this worked great on my vibrant!! acquired a gps fix within minutes for first cold start, then within seconds for the next time gps turned on! now there are no cons for the vibrant in my eyes :D THANK YOU XDA MEMBERS! using Nero v5 btw
 

KWKSLVR

Senior Member
Oct 9, 2010
884
332
Birmingham, AL
holy moly this worked great on my vibrant!! acquired a gps fix within minutes for first cold start, then within seconds for the next time gps turned on! now there are no cons for the vibrant in my eyes :D THANK YOU XDA MEMBERS! using Nero v5 btw

I saw improvements with Nero v5 as well. Bionix V with the KA7 modem and kernel gives great performance as well. I'm glad it worked for you!
 

Yuvan

Member
Oct 12, 2009
19
2
After reading through a gazillion posts in the Vibrant section of XDA, I finally got some decent locks on my GPS. Bought my phone from private party seller, which has a manufactured date of October 2010. I upgraded to official Froyo KA6 and the GPS became completely unusable. Prior to the update, I locked onto the GPS about 4 times over the course of 2 weeks, but at least I was able to get a lock.

The fix for phones manufactured October 2010:
Samsung’s GPS Restore tool found in the Android Market. Run the app outside in open skies since this particular GPS is beyond **** to begin with, so it’s worse indoors. If it doesn’t work at first, try again! The GPS is far from perfect, but it works to tolerable levels now.

To OP, please add this to your original post for easier reading for others looking for GPS fixes.

PS- **** you Samsung and TMobile. Thank you XDA contributors.
 

cowppl

Senior Member
Sep 30, 2010
71
3
California
For those who think the GPS is good, I say travel a bit. I lived in Fresno and my GPS was near perfect. It used to drift a bit, but was really reliable. I went to LA, and my GPS was completely broken. Tried the GPS fix and it said it locked on to more sattelites but it kept jumping. Three quarters of the time, it just wouldn't lock. I am currently overseas in South Africa, and the GPS wont even lock on to one sattelite. It seems depending on your location, the Vibrant's GPS can either be near perfect or completely useless
 
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lkt01071

Member
Oct 21, 2010
43
9
In addition to the GPS hardware fix I did the following:

First, make sure you have working WiFi and/or 3G data and it's working well.

Open your phone dialer and enter *#3214789650# (I like to save *#3214789650 to a google contact for future reference)

Under Application Settings use the following options:
Session Type -> Tracking
Test mode -> H/W Test
Operation mode -> H/W Sensitivity Test
Start Mode -> Cold start
GPS Plus -> ON
Dynamic Accuracy -> ON
Accuracy -> 50
GPS Logging -> OFF


Next go into SUPL/CP settings and set the following:
Server FQDN Type -> Custom Config
Server: -> supl.google.com (others have suggested supl.nokia.com)
Server Port -> 7276 (yes I know 7275 is normally the default)
SUPL security -> ON
AGPS mode -> SUPL


Go back to Home and reboot your Vibrant
Go back into LBS test mode (you saved it as a contact right?)
Select Delete GPS data
Select Get Position Test
Wait up to several minutes until you see Latitude/Longitude/Accuracy *green letters. (move to open sky if this part takes forever)
Lastly, go back into Application Settings and change Start Mode -> Hot Start.

This worked really well for me. After flashing Bionix-V I couldn't lock locks and accuracy as good and quick compare to Axura 2.2.7.1.

I tried Samsung Restore App and didn't get much differences, then I tried what you have suggested and it got 12 satellites and locked on to 10 of them in 5 second from COLD START!.

Thanks and I got a even better gps than I had from Axura.

Btw, the only differences in settings in LBS for me are:

Test mode -> H/W Test
SUPL security -> ON

Not sure if those were the cause of the sudden perf. increase!
 

AEguyNYC5

Senior Member
Dec 23, 2010
95
5
New York
Good luck to you. I hope they actually fix it instead of doing a stupid reset which I could have done myself. BTW it still didn't work after they "RESET" it.



The bums at Samsung sent me the same email they sent you. This phone is like a girl with a pretty face, you know she probably is no good for you but your a sucker for that face (in this case, the screen). Hopefully Samsung starts selling the screens to other companies soon so I dont feel forced to buy another Samsung after this junk and their crappy service. Once I receive it I'll be opening it up again see what bending or soldering I do.
 

AEguyNYC5

Senior Member
Dec 23, 2010
95
5
New York
Solder question

For the guys that have done the soldering, is there a specific thickness of solder on the contact you recommend? This is why I find cooking so difficult, I ask my mother ok how much cinnamon, cloves, sugar, I put to make the oatmeal how you make it? She says JUST A LITTLE BIT, ok well that leaves me with no clue at all, do you guys suggest like 1/64, 1/32, 1/16? What is a good amount? Me and my shaking hands will turn this phone into solder soup. Thanks
 

T313C0mun1s7

Senior Member
Nov 24, 2010
422
73
Lake Havasu City, AZ
For the guys that have done the soldering, is there a specific thickness of solder on the contact you recommend? This is why I find cooking so difficult, I ask my mother ok how much cinnamon, cloves, sugar, I put to make the oatmeal how you make it? She says JUST A LITTLE BIT, ok well that leaves me with no clue at all, do you guys suggest like 1/64, 1/32, 1/16? What is a good amount? Me and my shaking hands will turn this phone into solder soup. Thanks

This is very small, surprisingly small. I personally like to keep a nice large spool of my favorite solder around which is suitably small diameter, If I need to do larger work I just feed it faster.

Here is what it says on my spool:
  • Ratio - 60/40, Tin/Lead
  • Type - 370 Flux, 5 core
  • Diameter, 0.56 mm
 
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AEguyNYC5

Senior Member
Dec 23, 2010
95
5
New York
This is very small, surprisingly small. I personally like to keep a nice large spool of my favorite solder around which is suitably small diameter, If I need to do larger work I just feed it faster.

Here is what it says on my spool:
  • Ratio - 60/40, Tin/Lead
  • Type - 370 Flux, 5 core
  • Diameter, 0.56 mm

Wow that is as specific as anyone can get :eek: Thank you so much! Time to operate.
 

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    First off, I want to say that Plato56 was the first person to try this, and I want to give all credit where credit is due. Several others have applied this method, including myself, with great results. I apologize for not knowing everyone and I apologize if any of this is not clear. Please let me know and I will clarify the best I can and update this original post.

    Ok, the other thread found here is close but the wrong contacts are circled. I've uploaded several pics to reference as you read through this post. The first pic has the correct contacts circled. The contacts circled in the other thread are for the cellular radio.

    So What's The Deal With The GPS on my SGS!?

    Essentially, the problem is two fold.
    Problem #1: Samsung has no clue how to put out decent firmware.
    Problem #2: The copper contact that Samsung chose to connect the GPS Receiver to the GPS Antenna is about the crappiest selection they could have possibly made.

    THE PURPOSE OF THIS THREAD IS TO ADDRESS PROBLEM #2. If we address and solve one then we can (hopefully) tackle the other effectively one day. Here is a technical, but relatively easy to understand explanation of why Firmware alone can't fix the GPS problems that plague ALL SGS phones (even if your GPS is "fine" it still has weak SNR Numbers)

    Explanation (Courtesy of T313C0mun1s7):

    Q) Is it hardware?
    A) It's complicated. We are talking about very high frequency RF here, you gotta understand how electricity acts when you reach these frequencies to fully get this, but I will summarize. At zero hertz or DC current electricity flows through the body or center of the conductor. As long as you have enough conductor to carry the required current you are good. So the type of spring contact they used is fine for DC, in fact I went looking for replacement contacts and the only thing I can find are designed for either battery tabs or for grounding contacts. As you go higher in frequency the AC current of electricity takes on what we call skin effect, it travels as waves around the surface of the conductor. For this reason large diameter, low loss coax usually has a hollow center conductor. It make no difference electrically and makes it more flexible, lighter, and less expensive because it saves copper. Connections have to be solid and shielded because the RF can "leak", noise can be introduced, and the conductor should be tuned to the frequency carried. In short, these spring connectors are about as bad a connection as you could have picked. It is not enough that they touch the pad, you need good solid contact for a good transfer with the skin effect and to minimize loss. It seems that this problem is exasperated by poor contact. This fix it to simply improve the contact by increasing the pressure and hope to minimize the ill effects of this poor choice of contact design. To complicate things there are in fact things that can be done in software to improve the situation - this made trouble shooting harder because people tend to see these things as black and white and therefore either hardware OR software. If you want to know how software can affect this, then you will need to read back through the thread as I have already explained it twice and this answer is already too long.

    Q) Should I ever expect a fix?
    A) Read the OP. It was "fixed" (ie they improved the connection, but they did not re-engineer a proper fix) already. It seems if it was made in September there is a good chance it is ok or marginal. If it was made (or possibly re-manufactured?) in October it seems they are at least as good as the fix we are applying in this thread. Either they are using better contacts or they are increasing the angle to apply more pressure.

    Q) Will T-mobile replace it?
    A) They recognize the problem. This is what the app Samsung released is for. It resets everything to the stock settings (and nothing else). If you use it and can show unacceptable performance with the GPS (via the measurements the app makes - it is the official guide replacement), then they should replace the phone for you without any fight.


    Now that you know why you should consider applying the hardware fix to your SGS, read on to determine if it may actually help your situation. I.E. does your unit's manufacture date and/or modem make this modification worth your time?

    Prerequisites (Courtesy of T313C0mun1s7)
    If you don't yet have at least JI6 then you need to be at least at that modem level FIRST. If you are already using the JI6 (or newer) modem and your GPS still sucks AND your phone was manufactured prior to October, then try this. Otherwise don't expect results. To determine your manufacture date, look on the box. If you no longer have the box, then look under the battery. The middle line has the serial number marked with a S/N. To the right of that will be a set of numbers with a period in the middle. It is month and year in European format, so 10.09 would be September of 2010.

    To summarize:

    * Phone made in October 2010 or after - this should not be needed
    * You have not upgraded to at LEAST JI6 - then do that FIRST


    Steps To Apply The Hardware Fix:

    NOTE THAT THIS TECHNICALLY VOIDS YOUR WARRANTY especially if you choose the alternate method that involves a soldering iron
    However, there is nothing noted on the phone that says if you remove this or go beyond that your warranty is voided.

    Also, as goes without saying, don't blame me if you snap your GPS Antenna Contact off, break your plastics, or lose the ability to procreate!!! ;)

    * Turn off your GPS and shut down.

    * Remove the back of your SGS and take out your battery, SIM Card and MicroSD Card.

    * Remove the 7 screws that hold the back plastics. All you need is a Philips Head screwdriver from any jeweler's kit or glasses repair kit (you can get one from CVS/Wal-Mart, etc). Here is a video that shows you how to open up your phone. Take your time with this. I know it seems unsettling at first, but everything will be OK as long as you take your time and use a little common sense!

    Be sure to watch for three small things after you get the back off. If you aren't careful, all three will sprout legs and run away ;):
    1) Volume Rocker
    2) Power Rocker
    3) A little round plastic circle next to the lower right of your SIM Card slot that may fall out

    * Refer to the 3rd and 4th pictures I uploaded (courtesy of androidmonkey). These photos depict the CORRECT CONTACT to gently bend up. The 4th photo depicts the position your contact should be in. You'll probably find that yours is laying flatter and thus isn't making contact with the GPS Antenna (which is on the plastic backing that you removed). As I said a second ago, gently bend this contact up. I used a flathead screwdriver from a glasses repair kit. It doesn't take much bend this contact. I started from the side that the fourth photo depicts. After I got the contact up a bit, I moved my screwdriver over 90* where the hump is and pried a little more. That's it! It's really simple. Just don't go happy with your bending. I have no experience replacing a snapped piece of copper so I can't be of any help if you destroy yours.

    * Button everything back up. The back plastic will pop back in 10000% easier than it came off. Put the screws back in, pop your SIM and MicroSD back in and your battery. When you boot back up, you might wanna clear your GPS settings just for the heck of it. I did. DO NOT be shocked if it takes a few minutes to get a lock. It's probably the first time your SGS has ever had a real chance at a lock. Subsequent locks (Hot and Cold Start) will be faster.

    * Boot up, leave your GPS off. Just because it can't hurt, clear your GPS settings. Here's how:
    1) Download this app http://xdaforums.com/showthread.php?t=775154
    You can find it by searching for "sgstools" in the market. Click on Secret Codes then Lbstestmode. At the bottom you'll see "Delete GPS Data". Just click that!

    OR

    2) Open your dialer and hit *#*#1472365#*#*
    Click "Delete GPS Data".

    * Turn your GPS on. Wait for a lock! If you want to know what's going on, download two apps:
    "GPS Status & Toolbox" by EclipSim
    and
    "GPS Test" by Chartcross Limited

    That's it!

    ALTERNATE METHOD - ADDING SOLDER TO YOUR GPS CONTACT

    *WARNING* As I mentioned earlier IF YOU CHOOSE THIS METHOD THERE IS ZERO CHANCE OF YOUR PHONE REMAINING UNDER WARRANTY *WARNING*

    If you feel inclined to modify your phone in a much more permanent way, you can opt to add some solder on top of the contact (no need to bend the contact up, in fact, don't). I attached a zip with some pics that show what two posters, regp and Mannymal did. I've soldered a few things in the past, but I'm by no means an expert. If you choose to do this, a few things to remember.

    * First, seriously consider avoiding this if you have no experience with a soldering iron. In what I've seen on a limited base, you'll get minimal SNR gain in return for the effort that goes into this. I can't emphasis this enough.
    * There are probably a 100 tutorials on how to solder floating around on YouTube, watch them (all).
    * The absolute largest diameter solder I would use is .022.
    * Find the smallest tip possible.
    * Heat the CONTACT with your soldering iron, not your solder, or you will create what is called a cold solder joint that will probably lead to your GPS not working at all on down the road. You have to get the contact hot enough to receive the solder, which is touched to the part (in our case, the contact) that you want to apply the solder to.
    * Be careful not to make your solder to high. I suggest looking at the photo that shows the angle of the contact after it's been raised and using that as your benchmark. We want to make contact with the GPS Antenna, not break the thing when we snap the back plastic on. ;)
    * If you end up with two much solder you can either clean the tip of your soldering iron and touch the hot tip to the solder to remove some or you can use an emery board to file it down.
    * Use an small emery board (nail file essentially) to file down and smooth off your joint. I suggest doing this holding the phone upside down so you don't end up with 1000 tiny solder particles floating around your phone.
    * REMEMBER, phones are tiny. These boards are tiny. A soldering iron that is too hot left on ANY board for too long will destroy it. Multiply this rule x10 for delicate parts.

    Good luck. ;)

    Observable Data Changes
    (Grabbed from this thread after several days of playing with this fix).
    Accuracy: 16-28 feet stationary 38-50 feet moving (moving accuracy has improved and is now on par with stationary numbers since I started running the Stock JL4 Rom)
    Average SNR: 22-35. Obviously you'll always have one or two that are lower and one or two higher. My max I've observed was 42.
    Number of Sats Locked/In View: 8/11 most of the time. Yesterday afternoon I was locked on 10/10 with a 22 foot accuracy inside. I've had 11/14 before as well, just depends on the time of day.
    Cold Start Lock: 30 seconds
    Hot Start Lock: 5-15 seconds

    For reference, my Garmin Nuvi is currently connected to 7/10 with a 16-18 foot accuracy and my Vibrant is connected to 7/10 with a 21-25 foot accuracy. (stationary of course)

    Unnecessary re-routing: No
    Wandering on Google Nav/Lost Signal with Nav: Very rarely. For me it happens when I lose signal which is only if the phone is resting on my jeans. If it's in my cupholder, center console, hand, etc it's fine. Earlier today I lost signal with it in my cupholder but I was traveling in an area where my Garmin Nuvi only had a connection to 5 satellites.
    My Tracks: No data from me yet

    There are some after screen shots in this post.

    Other notes: I'm on the road a lot. Today is my first day to really extensively test it. Basically, it's MUCH better. Is it perfect? No, but I will say that unlike these other fixes that involve changes in lbstestmode and reset apps that only last for a couple of hours at best, my GPS performance has been very consistent ever since I adjusted the antenna contact. Is it as good as my old Blackberries with signal strength? No. How does it compare to other Android devices? I have no clue.

    What I do know is that it works well enough for me to be comfortable not having to grab my Nuvi everytime I switch vehicles.

    Wrap Up
    I hope this works for those of you like me that have tried almost every firmware update, tweak, etc. Between this fix and JL4, all I can say is that this device is probably as near to perfect as it'll ever be. I've been running this fix for well over a week and I've experienced no signs of the modified contact losing it's contact with the antenna.

    If You Still Have Problems
    * Even though you used the Samsung GPS Restore App (Found in the market for Vibrant/Captivate only)
    * Even though you deleted GPS Data
    * Even though you have your WiFi Off like Plato56 recommends in this post
    * Even if you tried a full system wipe

    Don't panic if you don't have a ton of locks. Like mentioned above, there is still a firmware component to this issue. I see times where mine doesn't want to lock. Usually if I turn GPS off and then turn it back on it runs smoothly from there on out. Depending on where you live, time of day may make a difference. Inevitably, in the afternoons I may only get 6 of 11 locked on. All other times I can get 9-11 of 11 or 11 of 14, etc. Bear with it. This fix is NOT a silver bullet, but give it a day or two of reasonable playing time to determine if it helped.

    For example, right now I'm indoors locked on 7/11 with a 21 foot accuracy and SNR's averaging 31. I used to see 0/3 with SNR's averaging 29. That's a definite improvement. If any other Android was in the same position it would probably show 8/11 with a 10 foot accuracy and SNR's averaging over 65.

    So take it for what it's worth, but the fix is DEFINITELY worth the effort!

    ADDITIONAL TWEAK
    Check out this thread here and read through the OP carefully. A few days ago I flashed "S.gps.zip" and I've had great results with it on Bionix 1.3.1 with the KA7 modem. I didn't see an increase in accuracy, but I did see a HUGE improvement on the speed my GPS locked and the number of birds locked too. I played around with all of the 2.2 modems last night and they all saw improved results.

    If you decide to flash one of those zips, I recommend making a Nandroid backup first. In reading through the thread it appears that there are a few people that had their flashes result in broken GPS's. I have no idea why, I'd imagine it's because they didn't clear GPS data and they just think it's broken. I recommend making a backup, shutting off your GPS, booting into CWM, flashing the zip, rebooting, clearing GPS data, turning your GPS on and enjoying locks. And, as always, I recommend using GPS Test by Mike Lockwood to test your GPS every time you make a change.

    The Super GPS should work on any ROM on an Vibrant, but it looks like a lot of people have tried it on 2.2 ROMS so be aware that, as always, there's the chance you may brick your device. If it works for you, be sure to thank jellette for his work. As always, I take no responsibility if this messes up your phone. I'm just relaying what worked for me. :)

    UPDATE: 7/31/11
    I should have posted this a couple of months ago. I also have a theory about why sometimes this fix fails over time. For example, I run Overstock 2.4.1 and I often flash the S.gps2.zip when I redo my system. It's been a fantastic combo on Bionix 1.3.1, but often, after a few weeks my GPS begins to turn retarded and will eventually no longer lock. In the past I've always believed it's purely because the antenna contacts have started to relax. However, what I've discovered is that when I go back into CWM and reflash my kernel and reflash the GPS zip, everything is happy and perfect again. I'm by no means a hardware genius or a developer. I'm just an average end user that loves to tinker with things and be methodical in testing, but I'm starting to believe that there truly is something going on that corrupts our GPS Drivers over time (in reference back to how we know Samsung screwed the pooch on firmware for the GPS Receiver).

    So, that said, before you crack your phone open over and over yanking and bending on contacts, reflash your kernel and the GPS Zip of your choice. And, like I've always said before, if the hardware fix doesn't seem to work for you when it seems to work for others on the same ROM as you, try another kernel, and try it more than once. I still fully believe that every GPS Receiver on every SGS can be made usable. It's not perfect, but it's a strong improvement from not being able to obtain a lock. http://xdaforums.com/showpost.php?p=16026963&postcount=12
    8
    Q&A

    This thread is getting long so I am creating this Q&A post to answer many of the most common questions.
    Due credits go to those that originally asked and answered these questions. Obviously this thread is the result of the efforts of many people.

    Q) Is it a hardware issue? Why do different ROMs / Modems effect this?

    A) It's complicated. We are talking about very high frequency RF here, you gotta understand how electricity acts when you reach these frequencies to fully get this, but I will summarize. At zero hertz or DC current electricity flows through the body or center of the conductor. As long as you have enough conductor to carry the required current you are good. So the type of spring contact they used is fine for DC, in fact I went looking for replacement contacts and the only thing I can find are designed for either battery tabs or for grounding contacts. As you go higher in frequency the AC current of electricity takes on what we call skin effect, it travels as waves around the surface of the conductor. For this reason large diameter, low loss coax usually has a hollow center conductor. It make no difference electrically and makes it more flexible, lighter, and less expensive because it saves copper. Connections have to be solid and shielded because the RF can "leak", noise can be introduced, and the conductor should be tuned to the frequency carried. In short, these spring connectors are about as bad a connection as you could have picked. It is not enough that they touch the pad, you need good solid contact for a good transfer with the skin effect and to minimize loss. It seems that this problem is exasperated by poor contact. This fix it to simply improve the contact by increasing the pressure and hope to minimize the ill effects of this poor choice of contact design. To complicate things there are in fact things that can be done in software to improve the situation - this made trouble shooting harder because people tend to see these things as black and white and therefore either hardware OR software. If you want to know how software can affect this, then you will need to read back through the thread as I have already explained it twice and this answer is already too long.

    Q) Should I try this fix?

    A) Only if you can not get your phone replaced under warranty. If you can not and meet the prerequisites in the OP, then you are a good candidate.

    Q) How do I update to JI6? In the release notes of the Super_IO kernel, it mentions it has the UVJL1 modem. is this more recent than JI6??

    A) Yes, JL1 is more recent than JI6. The nomenclature uses lexicograpical unicode values.
    1. Check the first unit. The first unit in JI6 and JL1 are both 'J', so look at the next unit.
    2. 'I' in the former, 'L' in the latter. 'L' comes after 'I' in the alphabet, so it's more recent.
    3. You can stop here, because you've already determined that JL* is more recent than JI*. Any units that come after this are to distinguish within the L- or I-series.

    Q) How do I reset the GPS setting?

    A) Open your dialer and hit *#*#1472365#*#* or maybe *#3214789650# (I need clarification on these)
    OR
    The Samsung GPS Restore app (APK attached to this post)
    OR
    Since the Feburary 2nd, 2011 Market update you can find it here https://market.android.com/details?id=com.sec.samsung.GpsRestore

    Q) Should we assume that any phone manufactured before 10/10 has these problems?

    A) No, I would not think so. Something like this is usually a intermittent manufacturing flaw and would not affect everyone or there would be an even larger outrage about it.

    Look at it this way. The spring contacts were designed to make contact without too much pressure when the back is properly in place. GOOD engineering would have accounted for slight variations in manufacturing and quality control and would have made the spring contacts overshoot the required distance a little to assure 100% contact in all situations. In this case I think they forgot to account for that and designed them to just touch, invariably some make intermittent contact and some fall just short of good solid contact (there are prior posts about how poor contact can get worse over time due to oxidation and arcing), but at least we have no reports of totally non-working GPS where they would have failed to touch outright. Chances are when October came around one of two things happened.
    They decided to fix the issue and reenginerred the design to make better contact
    The manufacturer ran out of the old contacts the the new shipment just work better

    Either way, although this is a common issue, I don't see the evidence that it affected all pre-October phones.

    Q) Any hints on how to get the back off after removing the screws? I watched the YouTube video, but I'm not having any luck with my normal sized fingernails.

    A) It is very stubborn, the most important tool you have is patience. Just take your time. If you really need more than just you fingers here are some other options.

    Set of Safe Open Pry Tools - http://www.repairsuniverse.com/prytools.html
    Thinner than credit card type cards such as a Bi-Mart membership card, plastic business cards that are 1/2 thickness of a credit card, laminated ID badge, old Subway rewards card.
    Guitar Pick
    The plastic from a clear "clam shell" type package that everything seems to come in now. You know, the ones that seem impossible to open.

    Q) CRAP!!! I BROKE MY TAB (This question covers Soldering)

    A) Relax, take three deep breaths, all is not lost.

    What you want to do is replace the tab with a small mound of solder to bridge the space between the boards and create a contact so the two pads touch. You want a decent amount of surface to touch and you want it flat for the best contact. You need the mound smooth and round because you are working with high frequency signals. Follow the instructions below carefully. If you need more details they are in this thread.

    1) If you are experienced in soldering most will be second nature to you except for the fact that you are not actually soldering anything to anything, you are just making a mound on a pad. If you are not experienced then the first step is to WATCH THESE VIDEOS (A) and (B) then PRACTICE until you are proficient in the basics of heating, soldering, and removing the iron cleanly leaving a good joint.
    2) Read this comic book (trust me) --> http://mightyohm.com/files/soldercomic/FullSolderComic_20110409.pdf
    3) Now if you are confident that you are ready to actually touch a hot soldering iron to the inside of your phone lets continue.
    1. De-solder the old broken contact from the pad using the soldering iron and either some wick or a solder-sucker (you can also use a cheap rubber bulb, but they rarely work well)
    2. Use the soldering iron and wick or solder-sucker to remove any remaining solder from the pad. It can still be silver, but should be flat.
    3. Realizing that you will remove a little solder with the iron when you pull it away, make a small, smooth, shiny, and round mound of solder on the lower pad just a little taller then you need for good contact.
    4. It is important in this step to not leave any metal filing behind on the board or it might short something out. So do this step holding the phone upside-down so they fall away. File the top of the mound with an emery board so you have a flat spot parallel with the pad. Don't file too much at first.
    5. Check the height of the mound by puting the top board back on. If needed file a little more and recheck. Go slow, don't try to take too much off at once. When the hight is right it should just barely be too tall. You want good solid contact, but you do not want the board to be stressed or bend.
    6. If all looks good check again for hidden shavings and blow it off real good just to make sure.
    7. If you mess up at any point just de-solder the pad and try again.

    Q) What are people's setting in LBSTestMode?

    A) Factory Defaults - an earlier question covered how to get back there

    Q) Will this work with the GT-I9000 or the Captivate?

    A) Most likely, yes. We have even had some people with those phones report back with positive results.

    Q) I did this hardware fix, but I am still losing locks. Now what?

    A) Here is what the OFA (Original Fix Artist) Plato56 has to say:

    1. Before anything else, make shure your WiFI radio is OFF. I dont mean not connected, I don't mean out of range, I mean hardware swiched off threw your settings or via the drop down status bar.

    2. Use the Samsung GPS restore to get you LBS settings to default.

    3. Update your modem to one of the 2.2 versions. Im particularly happy with JL4 modem myself

    4. Learn to use ODIN!!!! Use this to reload your firmware of choice. Prior to flashing you favorate ROM, Always flash back to JDF (BONE STOCK FIRMWARE).

    5. If you dont know what im talking about in 4, then go to the developers section and read, read, read.

    6. If you have any other questions refer to sujection 1 first, then ask. Honistly, alot of people have put some work into verifing if this fix works and testing with various software, the least you can do is read this body of work and you just might end up with a working GPS.

    7. My last tip of the day. Be patent with your first locks, the GPS does improve the more data it collects. This also means dont delete your GPS data unless you changed modems or are having real lock and or accuracy issues

    Q) Does this fix drift?

    A) There have been a couple that have mentioned that it does fix the drift, but I think there may have been others that say they get better locks but still get some drift. I do believe though that everyone who has done the driving test with it has reported that it tracks better now and actually shows them on the correct roads, where before it didn't.

    Q) What are the other contacts?

    A) Opposite side is Wi-Fi, bottom is cellular.

    Q) OK, so I can bend it up, or replace it with a bit of solder. Is that all?

    A) Of course not. Some like to stick a little piece of plastic under the tab rather than try to bend it. Just a little sliver about as wide as the contact cut off a credit card should work. Your Mileage may vary, in my mind if you drop the phone that plastic is gonna be floating around in there somewhere.

    Q) So inside I see. . .

    A) Stop! go outside. GPS was not designed to help you get from your bathroom to your kitchen. GPS signals are low power signals that have to travel all the way from an orbital satellite. Low frequencies penetrate well, and bend around objects, but they require a lot of power to transmit over distance. High frequencies travel much further with less power and remains in a fairly strait line, but it does not penetrate very well. Guess what GPS uses. So don't make it try to penetrate your roof.

    Q) So there are two apps listed to test GPS and . . .

    A) I've noticed a big difference between the two apps called "GPS Test". Try using the one written by Mike Lockwood (he's on the Google GPS team).

    http://www.androlib.com/android.appl...stest-qjx.aspx

    AND FINALLY

    Q) What does tonight taste like?

    A) Tonight tastes like chinese food and whiskey with coconut water :)

    A final note about satellites and tracking said hunks of orbital equipment
    I have noticed a lot of people are wanting to compare signal levels. This is fine on a superficial level, and there should be some level of consistency as long as you live on roughly the same latitude as the person you are comparing with. As Einstein said - everything is relative. With that in mind I thought I would share a post I made in another thread. There is cool stuff in here - so check it out.

    Another thing that you have to realize is that the satellites themselves are a variable. The only way to make a satellite stationary is to put it into orbit directly on the equator, falling at the exact same rate the earth spins, and in the same direction. Even at that there is still a little wobble in a figure 8 pattern.

    So GPS sats are anything but stationary, but they are flying at great speeds overhead coming in and out of view by their own rite at any time. At the speeds they fly the distances to you change by the mile rather quickly. So it should be no surprise that doing your testing repeatedly will never yield the same results twice. There are also a lot of other factors involved as well.

    The point is that you are now getting very acceptable and usable results from your GPS consistently, even if you never get anything as great as your first time. Maybe you will get those strong of signals again, but even if you don't you seems to be an par with what the majority of people have reported so far.

    FYI - If you would like to see some real time tracking of GPS sats that you should be able to see (THIS IS REALLY COOL) go to http://www.n2yo.com and click the GPS link at the top of the page. It will load a page of sats that are visible from your location. Click the select all box and then click the track selected satellites button. It will load a world map with the orbital paths of the sats, then the sats themselves. You can watch them move and even select them for more information on each satellite. This is not limited to GPS satellites if you want to keep playing with it. The point is that if you watch it for a little bit you can see pretty quickly as they move relative to the world map they are on just how many miles (or kilos) they cover in a fairly short time.
    4
    1. Put a small plastic spacer (made from clear plastic blister packs) in between the spring contact to reduce future deflection, and therefore increasing contact pressure. This may require some patience as the parts you are working with are very small (~1.5mm x 1.5mm)
    Big thanks for this :)
    I also used kind of a spacer made of a small (very small) piece of a rubber band.
    See attached images.
    Before #1
    P1075455_filtered_pc.jpg

    Before #2
    P1075445_filtered_pc.jpg

    After
    P1075462_filtered_pc.jpg

    My SGS GPS works as a charm after this fix :)

    /Per
    4
    SUCCESS!!!

    Ok I just wrapped up and I can report that the solder drop does indeed work. I've taken pictures for those who are interested in trying it.

    My first drop was too big and made the phone bulge so I reheated my solder gun and managed to take off about half of the solder that I dropped on. What I was left with was an odd not perfectly round blob but it seems to be good enough to have done the trick. GPS now locks instantly even from inside my room. And I do mean INSTANTLY. The midplate fit back on perfectly so I'm not sure exactly how much contact is actually being made between the solder and the midplate contact but its obviously enough. K, now pictures...


    Here is the final drop. I tired to take pictures that would display the size of it. Sorry for my lack of a macro lens. CLICK PICTURES FOR FULL RESOLUTION




    The Results..

    For reference this is what the weather here in the Bay Area is like today. All clouds and rain.



    The signal I was getting outdoor with ZERO obstructions. After many minutes.



    What I get now outside in my driveway post fix.


    What I get from my desk inside the house post fix.



    Hope this helps someone. Sorry for the lengthy post but I'm quite proud of my first solder job ever.
    4
    Caution: Technical

    ok, i'm not trying this in fear of jacking my phone up, but am i to assume that this gps problem with the galaxy is a hardware issue and not a firmware issue? lol i don't know if anyone mentioned this earlier in the thread i was getting bored of reading it....so with that being known lol i shouldn't EVER expect a fix unless they replace my phone and start fixing this with newer versions? lol this is hilarious lol

    All of your questions are answered in this thread (more than once, because people won't actually read).

    Here we go again.
    Q) Is it hardware?
    A) It's complicated. We are talking about very high frequency RF here, you gotta understand how electricity acts when you reach these frequencies to fully get this, but I will summarize. At zero hertz or DC current electricity flows through the body or center of the conductor. As long as you have enough conductor to carry the required current you are good. So the type of spring contact they used is fine for DC, in fact I went looking for replacement contacts and the only thing I can find are designed for either battery tabs or for grounding contacts. As you go higher in frequency the AC current of electricity takes on what we call skin effect, it travels as waves around the surface of the conductor. For this reason large diameter, low loss coax usually has a hollow center conductor. It make no difference electrically and makes it more flexible, lighter, and less expensive because it saves copper. Connections have to be solid and shielded because the RF can "leak", noise can be introduced, and the conductor should be tuned to the frequency carried. In short, these spring connectors are about as bad a connection as you could have picked. It is not enough that they touch the pad, you need good solid contact for a good transfer with the skin effect and to minimize loss. It seems that this problem is exasperated by poor contact. This fix it to simply improve the contact by increasing the pressure and hope to minimize the ill effects of this poor choice of contact design. To complicate things there are in fact things that can be done in software to improve the situation - this made trouble shooting harder because people tend to see these things as black and white and therefore either hardware OR software. If you want to know how software can affect this, then you will need to read back through the thread as I have already explained it twice and this answer is already too long.

    Q) Should I ever expect a fix?
    A) Read the OP. It was "fixed" (ie they improved the connection, but they did not re-engineer a proper fix) already. It seems if it was made in September there is a good chance it is ok or marginal. If it was made (or possibly re-manufactured?) in October it seems they are at least as good as the fix we are applying in this thread. Either they are using better contacts or they are increasing the angle to apply more pressure.

    Q) Will T-mobile replace it?
    A) They recognize the problem. This is what the app Samsung released is for. It resets everything to the stock settings (and nothing else). If you use it and can show unacceptable performance with the GPS (via the measurements the app makes - it is the official guide replacement), then they should replace the phone for you without any fight.