MAGNETIC ANTENNA Russian patent published in 2000 - IPC

FIELD: mobile antennas for building in miners' alarm receivers. SUBSTANCE: ferrite antenna used to receive alarm signals and low-frequency signals of magnetic field crossing rock mass has two series-connected inductance coils with ferromagnetic core including its linear and short-circuited parts; coils are connected in opposition and arranged at angle of 90 deg. for signal reception; they are mechanically fixed together on common chassis plate; tuning capacitors are connected in parallel with inductance coil leads. For simplifying antenna design and facilitating its tuning, only one capacitor may be provided in which case it is connected to vacant leads of inductance coil. Short- circuited core is solid structure which makes it possible to use ferromagnetic antenna within 5 to 40 Hz range. EFFECT: provision for eliminating microphonic effect. 1 dwg