Comparison of standard and digital observation at the Geomagnetic Adolf Schmidt Observatory Niemegk

For more than 4 yr the geomagnetic field has continuously been recorded by means of 3 proton magnetometers (F, X. Y) at Niemegk Observatory (1 value/min on punched tape). With this observation material, for all 7 geomagnetic components hourly means are calculated. The preliminary hourly means forF, Y, andX are published in the monthly report. As a rule, their comparison with the observatory data is satisfactory. Only with great geomagnetic activity (K ₁7) what was the case especially in 1982 relatively often, deviations in the hourly means up to 30 nT occurred. Obviously, during great magnetic disturbances the scanning rate of 1 min is not sufficient. In case of quick data variations, however, small technical defects in the electronic circuit can occur. Besides, these great differences could also be explained by errors which could be conditioned by the standard observational and processing methodology.