Instruction manual for Precision Graphic Recorder (PGR)
Sydney T. Knott, Warren E. Witzell · Woods Hole Oceanographic Institution eBooks · 1960
This manual describes the objectives, design, operation, and maintenance of the Precision Graphic Recorder (PGR), emphasizing its application to echo-sounding. The words "precision graphic recording" describe a method for displaying data by means of successive, precisely-timed rectilinear sweeps of a recording point or "stylus" across a long, moving strip of sensitized paper (Veatch and Smith, 1939, p. 61-63). The recorded data appear as dye-markings, shaded in proportion to signal amplitude along the sweep of the moving recording point.