Altitude Configuration
What is this? Do I have to use this? The answer: maybe. Depending on your GPS device.
According to NMEA 0183 standard your GPS device should send the altitude above sea level. But some manufacturers think it's better to send altitude above the WGS-84 ellipsoid. Good news is however that your GPS device might also send the difference between those values. For Germany this value is about 45 m.
So if you're not happy with your altitude, first try automatic correction. If that doesn't help, you can still set a manual correction value.
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