抄録
The general discussion is made on the stationary response of an electromagnetic seismometer, when the output of pickup is shunted by a condenser. This device can be used as a displacement seismometer up to the long period of ground motion of u=3-4, if a highcut filter is adopted for the frequency range of u<1. The magnification of the order of 10K is easily obtained even when the sensitivity of amplifier is of the order of 10μV/mm. The phase response is as well as the mechanical displacement seismometer. This kind of seismometer, therefore, is very suitable for the measuement of micro-tremor using a small size pickup.
