Sweep-synchronized positionable trigger and supplementary components

Abstract

This report describes the Sweep-Synchronized Positionable Trigger, together with its functions and supplementary components, as designed and built for use with the Precision Graphic Recorder (PGR) at the Woods Hole Oceanographic Institution. The positionable trigger provides a means for plotting a variable on the PGR record as a function of time, for triggering equipment such as oscilloscopes at any time, for displaying ship's heading, and for supplying, semi-automatically, ocean depth to a ship- board computer.