Аннотация:The paper addresses two issues. The first is the validity of the plane wave model when applied in the MT soundings (MT) collected in polar latitudes. The second is the validity of using two-component stations when survey in the conditions of a close ionospheric signal source in polar latitudes. To answer these questions, we consider the data from 5000 MT sites collected within a 120 × 80 km area in the north of Yakutia. The MT measurements in this area were conducted during half a year. During the three summer months, electromagnetic field was continuously recorded by the base station (remote reference) at the center of the area. This record is used to solve the first question. To answer the second question, we analyze the horizontal magnetic tensor yielded by processing the magnetic field records from the survey sites relative to the remote reference site.