Geodesy and Geodynamics Lab
Institute of Geodesy and Photogrammetry
ETH, Swiss Federal Institute of Technology

The Earth Tide Observatory is located in a specially built basement of the Satellite Observatory Zimmerwald. The Earth Tide Observatory is owned and operated by the Institute of Geodesy and Photogrammetrie (IGP), ETH Zurich.
Futher information can be found in a pdf project description file of the IGP, in the ECGN log file or on the swisstopo geostation web page.
Earth-Tide Gravimeter
The observatory is equipped with the LaCoste & Romberg Type ET gravimeter, serial number 25. This gravimeter uses an MVR electrostatic feedback system yielding a precision of better than 10-8 ms-2 for the one-minute averages of Dg.
Sampling is done once per second, average values are computed once per minute. Atmospheric pressure and temperature are measured and stored simultaneously.
The system is controlled by a LabView program running under Windows NT.
Absolute Gravity
Periodically absolute gravity measurements are peformed by visiting instruments, recently mostly by the FG5 absolute gravity meter of the Swiss Federal Office for Metrology (metas).