Digital seismograph for regional observing and the results of its testing

During the last few years digital seismic apparatus development was provided in the Institute of Geophysics. Some sets of digital seismic apparatus were made and tested at the regional seismic stations of the Carpathian network. The created equipment DAS is reliable and has sufficiently high operational properties due to use of modem chips and replacement of some analog chains (filtering, integrating, etc.) on their program analogues. The flexible algorithms of useful seismic signal detecting was applied. The digital form of records makes it possible to pass easily to true motion of ground under station, in case if the channel's frequency responses are known. Recorded by DAS seismograms of Vrancha earthquakes are unique for Ukrainian. Until them there was not such earthquakes records at the territory of Ukraine, which was suitable for studying of dynamic characteristics of seismic vibrations.