A long-period seismograph has been developed where the galvanometer photographic recording has been replaced by an electronic amplifier-filter circuit and ink recording, at comparable cost. The system has been tested carefully and found to be superior to conventional systems in some respects, especially in the stability of the transfer function and in the ease of installation and calibration. Critical but still satisfactory features are the dynamic range of the amplifier and the accuracy of the ink pen recorder. Both items are discussed in some detail.

First Page Preview

First page PDF preview
You do not currently have access to this article.