GPS sees no satellites on new build

ArduPlane
1

Hi everyone, I’m very new to Ardupilot, having only flown INAV quads before. I recently bought a PixHawk PX4 and am building a plane body, and think that I got everything right, except the GPS won’t see any satellites at all. GPS status changes between 0 and 1 sometimes, but the satellite count is always at 0. This is outside with a very good view of the sky.

I have no idea how I could debug, I see some ublox-related messages in Mission Planner (apparently the FC is trying to configure the GPS and succeeding, so communication is good), but I never get any satellites, and thus can’t arm. Can anyone point me to how I could debug this?

Specs: ArduPilot 3.9.x, PixHawk PX4, uBlox M8N GPS.

2

I left it a bit longer today and it found four satellites, but got stuck there. I left it for around twenty minutes but no more satellites were found…

3

Hello,

Show us a picture with GPS antenna and other transmitter (Video, telemetry) antennas. Your GPS antenna may be too close or in the same frequency (or harmonic) of video/telemetry Tx.

Marc

4

Hello!
Here you go:

I disabled the VTX for now, the only transmitters I have is the receiver’s telemetry and the 433 MHz telemetry antenna you see in the photo.

5

M8N GPS is really prone to RF noise. You could move it around and find a place where signal quality is fine. When done, you may have to adjust compass orientation parameters if needed.

Marc

6

I see, thank you! Is there another module I can get that is less sensitive perhaps?

7

Have you tried outside?

8

Yes, this was outside. It got up to 5 satellites.