CONTROL SYSTEM FOR ELECTRON BEAM MAGNETOMETER SENSOR

摘要

Described is a control system for an electron beam magnetometer sensor of the type adapted to detect disturbances in magnetic field, particularly the magnetic field of the earth, by means of a vacuum tube containing an electron gun which emits an electron beam and directs it between spaced pole pieces located within the envelope of the vacuum tube itself. The earth's magnetic field surrounding the tube is concentrated at the gap between the pole pieces such that the presence of a magnetically permeable body near the tube will alter the magnetic field intensity across the gap and cause the electron beam to deflect. The invention resides in the provision of electrical circuitry for sensing this deflection and for indicating the existence of a disturbance and its magnitude, which circuitry is capable of detecting small time varying signals in the presence of a strong static field.