磁偏角(D)的绝对值观测是任何一个正规地磁台都要进行的一项常规工作。CJ_6偏角磁力仪已在国内27个地磁台上被用作 D 绝对值观测的主要仪器。近几年地磁台资料评比会上反映的情况表明,由于各台在 D 绝对值观测中对各个技术环节的掌握和理解上都有不同,所以各台D基线值的观测精度的差别也较大,高的年均方差可达±0′.07左右,低的年均方差还>±0′.2 The absolute value of the declination (D) is a normal work to be done at any normal geomagnetic station. CJ_6 deflection magnetometer has been used in 27 domestic geomagnetic observatories D absolute value of the main instruments. In recent years, the situation reflected in the Geomagnetic Information and Assessment Meeting shows that the differences in the observation accuracy of the baseline values ​​of D are also large due to the different mastership and understanding of various technical aspects in D absolute observation. , High annual mean square deviation of ± 0’.07 or so, low average annual variance> ± 0’.2