Well guys,
I don't know why but I did about 10 flights today and the Navi board seems to work all ok again.
The only thing I did was cleaning all solder points yesterday on the pins I soldered.
I once had a problem with a connection between the pins because of the flux that is in the solder wire.
When you solder with standard solderwire you can see flux making an almost invisible layer around the solde point.
I heard that SOMETIMES this little layer can make a connection between solder points.
So.... maybe it was a very light connection between one of the pins (10pin or 6 pin) and I cleaned it without really seeing it.
With cleaning I mean: very
light scratching between the pins. I could see there was dry flux coming from the board between the pins.
A simple toothbrush didn't work so I used a small screwdriver.
Give it a try and let us know.
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Started Building: Jan 2008.
ME FC, V1.2 BR-Ctrl, Custom Carbon MK8 frame, 8x Axi 2217-20, 4x4900 30C Lipo, Futaba FF-9, Wi232, Epi-Osd, EzOsd, Yellow Jacket Pro Diversity, Headplay Video Goggles.