[Desire HD General] giegi_dc:
I'd like to make a unique single thread with all the issues related to gps on DHD and the procedures/tips to make it work better.

MY EXPERIENCE

I was ready to go to dinner to my girlfriend's uncle (50km far away). I bought my DHD two days before. Ok, let's try gps. Google navigator. Started driving and my phone didn't get a lock. After five minutes of driving, i needed some help from navigator. Nope, still no gps lock.:mad: I stopped the car, got out with DHD in hand and lock again in two minutes with the sky in sight. No problem until destination. At the end of the dinner, on the road again. For the first 3 minutes, gps lock. Then lock lost, gps icon blinking and nothing. Tried to reload the phone. Fast boot first time and complete reboot the second time. I didn't stop the car this time, tried while driving (my girlfriend handled telephone while i was driving :-) ).

It took 45 minutes to get lock again. :mad::mad::mad::mad:Thanks god, i learned the route on the journey there.

The same thing happened again three times in the next days.

I thought that some software installed corrupted my phone.....(sorry, i was used to the windows mobile whims!!!!).

Hard resetted, but the problem was always there. Without logic, sometimes i had gps lock, sometimes not. Sometimes my DHD was keeping the lock until destination, other times gps lock was lost while moving.

GENERAL CONSIDERATIONS

Not all the people complaints about gps on DHD. I don't know why but there are many people who have problems using it. I think that, except for the faulty devices with defective gps chip, the behaviour is the same for all devices. Only the people perception about the performances of gps are different, and their behaviours of use. I had different expectations about gps. I was used to start driving without gps lock, my HtcHD would have always found lock in one minute anyway. Even if moving, even if many clouds or raining.

People who arrived to Android coming from Windows Mobile do experience a general lack of speed in locking gps position and a very different way about gps is handled by the OS.

My DesireHD hardly locks gps where my previous HtcHD locked gps in few seconds.

The same difficulties I have now with DesireHD, I had them too when I installed Android on my HtcHD. But I thought it was the unstable Android SD ROM's fault.

Another issue is the speed of hot start: DHD seem to have a very very short term memory in fact of gps. Hot start is really hot only if you reconnect within short time.

My HtcHD was able to reconnect in few seconds even if hours passed from the previous lock, if not moved.

My new DHD needs more time to lock, even if the previous lock was 30 minutes before. It happens to take 45 seconds or more to lock again if the sky is not completely in sight.

Even if I get lock with GPS Status, shutdown the program and I reopen it few seconds after, gps lock is not immediate. It takes almost ten seconds to lock.

I think I have to forget the Winmo performances in fact of gps, on Android.

(I think it's the only thing i'm gonna be missing, anyway......)

I think i'll have to wait for the lock before start driving from now.

ISSUES EXPERIENCED BY USERS

- DHD locks gps but when moving it loses the lock and it stays for minutes (from 10 to 60) looking for it again. -

Let DHD get an outdoor strong gps lock for some minutes before starting to move.

- DHD is unable to find a lock. Phone never ever locked gps, whether indoor or outdoor, with the whole sky in sight.

Try resetting AGPS data and let your phone get a lock without data connection, outdoor with the sky in sight on a plain stable surface

If you never ever succeed to get a lock, you should consider to have a faulty chip on your device. I think it's better to contact HTC Repair service.

- DHD behaves with no logic. Sometimes it finds a lock in seconds, sometimes it takes ages to find a lock.

Let DHD get an outdoor strong gps lock for some minutes before starting to move.

- DHD is unable to find a lock if any data connection is available.

Try resetting AGPS data e let your phone get a lock without data connection, outdoor with the sky in sight on a plain stable surface

TIPS

Do all of these steps. And, except for the first, try to do them all the times you use gps. And evaluate the improvements, if there are.

One time procedure:

- Force the phone to lock gps without any data connection and check APN type (see below for the link to step-by-step procedure).

It is important to put the phone outdoor on a stable and straight surface in order to get a strong lock, with a complete view of the sky.

My advice is to empty a-gps data BEFORE doing this operation (this can be done with GPS Status - Menu => Tools => MAnage Agps state => Empty data - The program is free and doesn't need root permissions)

Before every use of gps:

- Use FasterFix (needs root permissions) to change NTP server zone. The system/etc/gps.conf file contains parameters for NTP server and AGPS data. In mine i find that the ntp server used is located in northamerica. I live in Rome so I use Fasterfix to change it, forcing to use european ntp server. I don't know why but Android changes by itself this file, putting again north america server, so i have to change it more than once in a day to keep it using european server.

NOTE: Fasterfix gives back an error the first time you open it, choose the seerver and try to apply it. Only the second or the third attempt, it returns an ok result. Don't mind error. Don't worry about it. Even if returned error, it did its job anyway.

- Synch Device clock with atomic time. I use ClockSynch (needs root permissions), but every program capable of doing the same thing can be used. This is intended to help device in calculating your position. More accurate time means less corrections by the software, faster position calculating and a more accurate position.

- Let the phone get a strong lock BEFORE starting to move with your car. A couple of minutes before, you should let your phone on a stable surface, with sky in sight. Outdoor, obviously. Better if outside the car.

This thing could seem stupid, i know. But let your DHD get the lock in a place where it has a good view to the satellites. Let it acquire precision (you can see it in the left middle part of the screen, using GPS Status). Start moving only when precision has reached a minimum value (expressed in meters/feets - lower value, more accurate). You will see that gps lock will be more and more stable than before.

- Use a task killer program to kill all the processes which may use gps. I noticed that if one or more program able to use gps have been left opened in background, sometimes, without logic, something goes wrong and Gps receiver is no longer reachable by software.

In this situation if I open GPS Status, I see gps icon blinking, but in fact no satellites are seen by the program. I mean that on the screen is not shown 0/3 or 0/5 satellites. On the screen i see nothing about the number of sats, neither 0/0, empty. And in some situations this thing cannot be true (i.e. if i am completely outdoor with a perfect sky view).

RESOURCES

Gps lock without data connection: http://wccftech.com/2010/09/09/solving-gps-nofix-problem-cyanogenmod-6-nexus/

Gps Status: http://www.appbrain.com/app/gps-status-toolbox/com.eclipsim.gpsstatus2

FasterFix: http://www.appbrain.com/app/fasterfix/com.Double.FasterFix

ClockSync: http://www.appbrain.com/app/clocksync/ru.org.amip.ClockSync

Advanced Task Killer: http://www.appbrain.com/app/advanced-task-killer/com.rechild.advancedtaskkiller

EDIT: I have a stock ROM. Nothing upgraded. The only modification is the root access permissions granted with visionary.