<p>The GPS module can't give you even an approximate position fix until it knows where the satellites are.  The satellites transmit this data (called an &quot;almanac&quot;) continuously, but it takes about twelve and a half minutes to send a complete copy, and it's only good for a few weeks.  If your GPS module has been powered down for longer than that, it needs to wait for an updated almanac before it can do anything.</p>
<p>(Your cell phone can get a faster fix by downloading a copy of the almanac off the Internet, but presumable your quadcopter isn't set up for this.)</p>

CC BY-SA 4.0
2021-08-10T02:11:35.317Z
2021-08-10T02:11:35.317Z
Mark
<p>I'd say if you get any satellites at all, the GPS module works and it got the almanac correctly. Getting only 5 sats after 10 minutes is indeed insufficient (8 is fine though).</p>
<p>It could be that this particular GPS module is not good enough, or it simply doesn't work very well at your flying site. Nearby trees, buildings, or even parts of your drone can interfere with GPS reception. It's also possible that glitches on the power supply line make the module reset periodically, so it never gets into stable operation.</p>
<p>Try finding a place with no obstacles around (a field outside the town) and make sure it's supply voltage is stable.</p>

CC BY-SA 4.0
2022-09-21T09:08:12.327Z
2022-09-21T09:08:12.327Z
Dmitry Grigoryev
<p>I got a new GPS for my Matek f405, and after I set it up and got betaflight to recognize it, I can't get any satellites. It's a BEITIAN BN-220T.</p>

CC BY-SA 4.0
2021-08-06T15:43:34.677Z
Are you testing indoors or outdoors?
Drones and Whatnot
CC BY-SA 4.0
2021-08-07T16:08:36.630Z
I am testing outdoors.
Vichot
CC BY-SA 4.0
2021-08-07T20:22:12.073Z
I left it for 10 minutes and it got 5 sats
Vichot
CC BY-SA 4.0
2021-08-07T20:22:57.337Z
The problem is that I don't think it is safe to fly with that little.
Vichot
CC BY-SA 4.0
2021-08-07T20:24:45.620Z
on the first power-up it can take a little while for the GPS to register satellites. How have you got your module mounted?
Drones and Whatnot
CC BY-SA 4.0
2021-08-07T20:35:00.603Z
on the top plate with the antena facing up.
Vichot
CC BY-SA 4.0
2021-08-07T21:04:46.303Z
could it be the country I'm at?
Vichot
CC BY-SA 4.0
2021-08-08T21:37:36.873Z
I got 8 sats but no more.
Vichot
CC BY-SA 4.0
2021-08-08T21:40:50.640Z
your mounting sounds like it is correct, so I’m afraid I’m not sure of the best way to fix this. I have heard people recommend a video by a YouTuber called TMac to get a GPS module to pick up satellites, and have also found this thread which may prove useful: https://intofpv.com/t-getting-gps-to-find-satellites
Drones and Whatnot
CC BY-SA 4.0
2022-09-21T17:23:04.920Z
The acquisition of weaker signals depends on SNR.  I'd wonder what noise reduction can be done for conducted and radiated noise.
Tony Stewart EE75
<quadcopters><betaflight><f4><gps>
Why doesn't my GPS get any satellites?
Vichot
# Why doesn't my GPS get any satellites?

(Asked by: username_0 on 2021-08-06)

I got a new GPS for my Matek f405, and after I set it up and got betaflight to recognize it, I can't get any satellites. It's a BEITIAN BN-220T.

**Tags:** quadcopters, betaflight, f4, gps

> **Comments:**
> **username_1**: Are you testing indoors or outdoors?  
> **username_0**: I am testing outdoors.  
> **username_0**: I left it for 10 minutes and it got 5 sats  
> **username_0**: The problem is that I don't think it is safe to fly with that little.  
> **username_1**: on the first power-up it can take a little while for the GPS to register satellites. How have you got your module mounted?  
> **username_0**: on the top plate with the antena facing up.  
> **username_0**: could it be the country I'm at?  
> **username_0**: I got 8 sats but no more.  
> **username_1**: your mounting sounds like it is correct, so I’m afraid I’m not sure of the best way to fix this. I have heard people recommend a video by a YouTuber called TMac to get a GPS module to pick up satellites, and have also found this thread which may prove useful: https://intofpv.com/t-getting-gps-to-find-satellites  
> **username_2**: The acquisition of weaker signals depends on SNR.  I'd wonder what noise reduction can be done for conducted and radiated noise.  

---

## 2 answers

### Answer by username_3 on 2021-08-10. Score: 3

The GPS module can't give you even an approximate position fix until it knows where the satellites are. The satellites transmit this data (called an "almanac") continuously, but it takes about twelve and a half minutes to send a complete copy, and it's only good for a few weeks. If your GPS module has been powered down for longer than that, it needs to wait for an updated almanac before it can do anything.

(Your cell phone can get a faster fix by downloading a copy of the almanac off the Internet, but presumable your quadcopter isn't set up for this.)


---

### Answer by username_4 on 2022-09-21. Score: 1

I'd say if you get any satellites at all, the GPS module works and it got the almanac correctly. Getting only 5 sats after 10 minutes is indeed insufficient (8 is fine though).

It could be that this particular GPS module is not good enough, or it simply doesn't work very well at your flying site. Nearby trees, buildings, or even parts of your drone can interfere with GPS reception. It's also possible that glitches on the power supply line make the module reset periodically, so it never gets into stable operation.

Try finding a place with no obstacles around (a field outside the town) and make sure it's supply voltage is stable.


---

