A cross-coupling computer has been built for the NOAA ship Oceanographer's Askania GSS 2 gravity meter. Beam deflection and surge acceleration signals are obtained, respectively, from the gravity meter and its associated Anshutz gyro table. These are multiplied electronically and filtered to give computed cross-coupling error. Cross-coupling error is recorded on an analog recorder, and encoded for processing by the shipboard computer. Comparison of trackline crossings where significant cross coupling was recorded showed that the average crossing discrepancy was reduced from 14.5 milligals (mgal) to 2.5 mgal when corrected. On a traverse of the Cape Flattery gravity range, gravity error was reduced from an average of about 12 mgal to about 1 mgal by correcting for cross coupling.

This report covers phase I of a plan to develop a telemetering hydrographic tide gauge system to provide real-time tidal data to hydrographic survey ships. Phase I included the design, construction, and testing of a telemetering system for use with existing shore-based portable tide gauges. The design requirements for the equipment and the operating characteristics of the system under a field test are described herein.