Calibration and testing

Abstract

The previous chapters have described how seismic instruments work. It is now time to describe how to calibrate and test the equipment. In the first instance, we often need to do some basic tests to evaluate if the equipment is working properly and, if it is malfunctioning, to try to figure out what is wrong. In the second instance, we need to know the system parameters in order to account for the system response (Chapter 6). In most cases, we can rely on manufacturers' parameters, and in some cases we have to, but instrument parameters might change with time, be wrong due to defects in the equipment or be unknown, so it is useful to be able to determine the parameters yourself.

This chapter will describe some simple tests. Do not expect to become an expert, however it is surprising how much can be done by simple means. The sensors are the most complex part of the seismic station, while the remaining parts have few parameters, so this chapter mainly deals with sensors.