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GPS signal loss

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I have a typhoon h pro never flown and noticed that I will get a gps lock with 8 or 9 sats and immediately I get a loss signal and still on ground. I performed an compas calibration again and accelerometer calibration as well. Now so you have a baseline I am not new to drone flying as I have flown my q500 for some time so I am not knew to the hobby. Any ideas what it is happening.
 
More information is needed. "8 or 9" is marginal if you mean drone satellites. We need to know:
1.) Is the drone outside with a clear view of the sky?
2.) If this was the first flight attempt on this drone, was the drone initially allowed to sit powered for a minimum of 30 minutes (probably a lot longer) to charge the little GPS battery and update the GPS almanac?
3.) If the almanac has already been updated, how long did you wait?
4.) How many drone satellites are showing?
5.) How many controller satellites are showing?
ST16 GPS.jpg
 
Last edited:
To add to the previous post remove the props, go into the settings where you access the compass calibration and turn off GPS then try to arm the motors. If you can arm the motors with GPS disabled then you are likely in good shape and need to leave the aircraft powered up outside with a clear view of the sky until the small battery on the GPS board charges enough to hold the Almanac downloaded from the GPS satellites.

If you are unable to arm the motors with GPS turned off, then connect the Typhoon H to the GUI on your PC and observe the Yaw display. If it is slowly changing then it is likely you are suffering from a failed IMU on the aircraft’s Flight Controller.
 
More information is needed. "8 or 9" is marginal if you mean drone satellites. We need to know:
1.) Is the drone outside with a clear view of the sky?
2.) If this was the first flight attempt on this drone, was the drone initially allowed to sit powered for a minimum of 30 minutes (probably a lot longer) to charge the little GPS battery and update the GPS almanac?
3.) If the almanac has already been updated, how long did you wait?
4.) How many drone satellites are showing?
5.) How many controller satellites are showing?
View attachment 27757
It was the first flight.
the sky was clear in sight
only 8 or 9 showed maybe 10
i did not let it sit in the sun for e tended time to update the almanac which was my first thought.
the drone had maybe two more satellites but the controller caught up so basically they were the same.
 
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It was the first flight.
the sky was clear in sight
only 8 or 9 showed maybe 10
i did not let it sit in the sun for e tended time to update the almanac which was my first thought.
the drone had maybe two more satellites but the controller caught up so basically they were the same.

If the drone has not been powered on since it was built the GPS almanac is surely out of date. And the GPS battery is probably dead. The GPS will work from the drone battery while the drone is powered on but will require 20 minutes or longer to update the almanac EVERY TIME the drone is powered off/on until the GPS battery recharges. At least enough to hold the almanac.
The GPS battery recharges very slowly. It takes a couple of days to recharge from full dead to fully charged, and it only charges while the drone is turned on. It does not have to be fully charged to work so the actual recharge time might be a lot less just to at least get it functional.
 
If the drone has not been powered on since it was built the GPS almanac is surely out of date. And the GPS battery is probably dead. The GPS will work from the drone battery while the drone is powered on but will require 20 minutes or longer to update the almanac EVERY TIME the drone is powered off/on until the GPS battery recharges. At least enough to hold the almanac.
The GPS battery recharges very slowly. It takes a couple of days to recharge from full dead to fully charged, and it only charges while the drone is turned on. It does not have to be fully charged to work so the actual recharge time might be a lot less just to at least get it functional.
based On your reply which I value btw my actions below what what I was going to do

weather is bad today and tomorrow but I was going to leave the drone on in house to charge gps battery.

when weather is Barr then let the drone sit outside to update the almanac

calibrate the compass again and accelerometer

i take it I don’t need to power up the controller to update the drone gps battery.
btw the drone was powered up since manufactured about 6 times but never flown. What are your thoughts
 
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based On your reply which I value btw my actions below what what I was going to do

weather is bad today and tomorrow but I was going to leave the drone on in house to charge gps battery.

when weather is Barr then let the drone sit outside to update the almanac

calibrate the compass again and accelerometer

i take it I don’t need to power up the controller to update the drone gps battery.
btw the drone was powered up since manufactured about 6 times but never flown. What are your thoughts
First thought is to do the troubleshooting steps recommended by @DoomMeister in post #3 above. That will help ensure we are not chasing the wrong problem.
My thoughts focused on the GPS almanac issue just because there is good probability of the GPS battery being dead. But most GPS problems we see on the Forum are related to the flight controller issue Doom is looking at. His techniques will go a long way to determine the actual issue.
The controller and camera do not have to be powered on during the GPS battery charge. Just the drone itself. It would be a good idea to remove the camera while charging to avoid overheating the camera internals.
Compass and accelerometer calibrations probably won't help much, but for the Typhoon H it won't hurt anything either. (different story for HPlus and everything after)
 
First thought is to do the troubleshooting steps recommended by @DoomMeister in post #3 above. That will help ensure we are not chasing the wrong problem.
My thoughts focused on the GPS almanac issue just because there is good probability of the GPS battery being dead. But most GPS problems we see on the Forum are related to the flight controller issue Doom is looking at. His techniques will go a long way to determine the actual issue.
The controller and camera do not have to be powered on during the GPS battery charge. Just the drone itself. It would be a good idea to remove the camera while charging to avoid overheating the camera internals.
Compass and accelerometer calibrations probably won't help much, but for the Typhoon H it won't hurt anything either. (different story for HPlus and everything after)
Thank you I will do as you suggested, thank you for the camera suggestion appreciate it, will let you know how I make out.
 
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I know the motors work as they engaged when I did have gps lock but the gps lost lock quickly and the message came up on the controller to maintain manual flight gps is lost.
That part is good, but does not address the issue of the staying in the GPS Acquiring stage for so long. The idea behind turning off GPS and attempting to arm the motors (with props off) while still in the Acquiring stage helps determine if the IMU is faulty. It is normal for the motors to arm once you get GPS Ready. Connecting to the GUI and observing the Yaw readout is also a good idea. It will also check the other major electronics.

You can probably get the almanac updated if you leave the aircraft powered up near a window or sliding glass door.
 
That part is good, but does not address the issue of the staying in the GPS Acquiring stage for so long. The idea behind turning off GPS and attempting to arm the motors (with props off) while still in the Acquiring stage helps determine if the IMU is faulty. It is normal for the motors to arm once you get GPS Ready. Connecting to the GUI and observing the Yaw readout is also a good idea. It will also check the other major electronics.

You can probably get the almanac updated if you leave the aircraft powered up near a window or sliding glass door.
Ok will check motor arming with gps turned off. I did leave the drone on in the house near window to charge the almanac battery and it did register 12 satellites for the drone . Will check motors as suggested.
 
Just to add further informations about satellites : not at all time a sufficient number of satellites is visible, depends from their position and altitude over the horizon.
There are some apps that can help to check their number along the day and choose the best moment for flying.
I use this app (for android....don't know if it's also available for IOS):
UAVForecast.com UAV Forecast
It's available on the play store.

Here a screenshot of today's conditions, as you can see it's not a good day for flying
Screenshot_20220313_075215.jpg
 
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Just to add further informations about satellites : not at all time a sufficient number of satellites is visible, depends from their position and altitude over the horizon.
There are some apps that can help to check their number along the day and choose the best moment for flying.
I use this app (for android....don't know if it's also available for IOS):
UAVForecast.com UAV Forecast
It's available on the play store.

Here a screenshot of today's conditions, as you can see it's not a good day for flying
View attachment 27759
That is awesome information thank you Pier
 
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Just to add further informations about satellites : not at all time a sufficient number of satellites is visible, depends from their position and altitude over the horizon.
There are some apps that can help to check their number along the day and choose the best moment for flying.
I use this app (for android....don't know if it's also available for IOS):
UAVForecast.com UAV Forecast
It's available on the play store.

Here a screenshot of today's conditions, as you can see it's not a good day for flying
View attachment 27759
Thank you I do use that app it is very useful.
 
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Ok will check motor arming with gps turned off. I did leave the drone on in the house near window to charge the almanac battery and it did register 12 satellites for the drone . Will check motors as suggested.
I did check the motors today with gps urned off and all motor’s engage. I let the drone sit yesterday with a fully charged battery with camera removed and the drone showed 12 satellites. It appears that the battery for the satellite almanac needs to charge fully so it will store the data. Will know later this week and let all know.
 
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I did check the motors today with gps urned off and all motor’s engage. I let the drone sit yesterday with a fully charged battery with camera removed and the drone showed 12 satellites. It appears that the battery for the satellite almanac needs to charge fully so it will store the data. Will know later this week and let all know.
It's better to leave the drone sit outside for at least 1/2 hour turned on (the ST16 can be left in off) to make sure the almanac is restored, this happens normally every 15~17 minutes.
At every flight, wait at least 3 minutes from the "welcome pilot" message before take off, this is a good practice to avoid gps loss and /or fly away.
 
I did check the motors today with gps urned off and all motor’s engage. I let the drone sit yesterday with a fully charged battery with camera removed and the drone showed 12 satellites. It appears that the battery for the satellite almanac needs to charge fully so it will store the data. Will know later this week and let all know.
The motor arming with GPS turned off is a good sign! Letting the aircraft sit powered up with the camera off for an hour or so several times will help charge the small GPS battery. A chance to get outside will let you know how this goes.
 
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The motor arming with GPS turned off is a good sign! Letting the aircraft sit powered up with the camera off for an hour or so several times will help charge the small GPS battery. A chance to get outside will let you know how this goes.
Will do thanks all will let you know once I get outside.
 
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Just to add further informations about satellites : not at all time a sufficient number of satellites is visible, depends from their position and altitude over the horizon.
To do this application to work correctly, you should compare visible sats by drone and by your phone. In the application, you can set what kind of birds will be added to the total count.

GPS, Beidou, GLONASS, Galileo are in your choice. Depending on the phone and android version, there is possible to be used assisted GPS and so on. In short, no reason to trust only by the application's recommendations.
 
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Agree... This application must be intended as an help.
I've set in the application to be used only GPS and GLONASS satellites, the same received on the drone, so the total count is more or less the same i normally see acquired on the bird.
 
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