Electronic Apparatus for Field Seismic Prospection; Apparatus for Controlling Artificial Seismic Shocks, Apparatus for Collecting Seismic Signals, for Analog Pre-Processing of Such Signals, for Analog to Digital Conversion Thereof, for Recording the Digital Data, and for Playback of Seismic Signals for Such Digital Data; Digital Processing Apparatus of the Recorded Digital Data; Electronic Apparatus for Field Electric or Electromagnetic Prospection; Sources in the Nature of DC or AC Power Supplies, Electrodes, and Interconnecting Circuits Therefor, Apparatus for Collection and Recording Signals from Earth DC or AC Signals; Apparatus for Preprocessing of Such Signals; Apparatus for Displaying Such Signals; Radionavigation Systems-Namely, Transmitters, Receivers, Transmitters-Receivers, Receivers-Transmitters and Associated Apparatus for Ambiguity Resolution and/or Corrections; Displaying or Processing Apparatus for Association to Radionavigation Receivers; Electronic Apparatus for Displaying Results of Digital Data Processing on Film or Paper, with Large Scale and Velocity of Operation; Electronic Apparatus for Angle Measurement; Digital Angle Coders; Electronic Position and Motion Detectors