PURPOSE: To eliminate influences of crosstalk by making the width of a return magnetic core, which constitutes a magnetic closed circuit together with a main magnetic pole, larger than that of the main magnetic pole and winding an erasing coil around this wide return magnetic core.

CONSTITUTION: In case of recording, lines 8 of magnetic force flowed out from or into a main magnetic pole 1 magnetize a recording medium 7 to form a closed loop through return exciting cores 5 and 11 and a connecting part 6. Meanwhile, lines 14 of magnetic force generated by an erasing coil 13 erase signals on the recording medium through the return exciting coil 11 and return to the return exciting coil 11 again. Since the width of the return exciting core 11 is very larger than that of the main magnetic pole 1, the efficiency of magnetization and erase of the recording medium 7 is high. As the result, the erasing current flowed to the erasing coil 13 is smaller than the current required for an exciting coil 3, and influences upon a magnetic field for main signal exist hardly because the magnetic path of the erasing magnetic field forms the closed loop with the return exciting core 11.