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Mobile phone compass is located by satellite, which is different from the traditional compass that relies on the earth's magnetic field to find the north and south. According to satellite positioning, we can accurately find the north and south poles of the earth, but according to the compass, there will be a lot of deviation. This is the so-called magnetic declination.
But since ancient times, the exploration of geomantic geography has always been based on the earth's magnetic field. The ancients did not have satellites, nor did they record mountains and rivers. Therefore, it is correct to use the traditional geomantic compass to survey geography. Baidu search Ding Dong compass has many related articles. worship
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