No. 3 + 1,**- Technical Research Report, Earthquake Research Institute, University of Tokyo, No. 3, pp. + 1,,**-. MT * ** *** Retrieval of Seismic Data Recorded on Open-reel-type Magnetic Tapes (MT) by Using Existing Devices Masaru NAKANO*, Hiroyuki KUMAGAI** and Jun OIKAWA*** Abstract Open-reel-type magnetic tapes (MT) were commonly used to record seismic and other observation data more than ten years ago. Although seismic data recorded on MT may contain useful information about past seismic activities, it becomes di$ cult to retrieve data from MT recently since the devices used to read and write MT have been disposed and replaced by recent higher capacity and portable recording devices. In this paper, we report detailed descriptions how to retrieve Kusatsu-Shirane seismic data recorded on MT using the existing devices and to decipher the data format without a priori information, which may be useful to retrieve MT data used in other seismic networks. Key words : Magnetic tape, MT, Seismic record, Data retrieval, Data format MT,*** UNIX MT MT MT MT CD MT MT MT +33,,**- 2,2,**- +*,* * ** *** * Graduate School of Environmental Studies, Nagoya University, Nakano et al., +332 ** National Research Institute for Earth Science and Disaster Prevention, MT *** Earthquake Research Institute, University of Tokyo. MT 1
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MT 7 1 MT + +323 +* ++ /* 1 JIE, MT +323 MT MT +323 +323 +323 + 0 0. -,/ -./. Kumagai, H., B. A. Chouet, and M. Nakano,,**, a, Temporal evolution of a hydrothermal system in Kusatsu-Shirane Volcano, Japan, inferred from the complex frequencies of long-period events, J. Geophys. Res., +*1,,,-0, doi : +*. +*,3/,**+ JB ***0/-. Kumagai, H., B. A. Chouet and M. Nakano,,**, b, Waveform inversion of oscillatory signatures in long-period events beneath volcanoes, J. Geophys. Res., +*1,,-*+, doi : +*. +*,3/,**+ JB **+1*.. Nakano, M., H. Kumagai, M. Kumazawa, K. Yamaoka and B. A. Chouet, +332, The excitation and characteristic frequency of the long-period volcanic event : An approach based on an inhomogeneous autoregressive model of a linear dynamic system. J. Geophys. Res., +*-, +**-+ +**.0. Nakano, M., H. Kumagai and B. A. Chouet,,**-, Source mechanism of long-period events at Kusatsu-Shirane Volcano, Japan, interred from waveform inversion of the effective excitation functions, J. Volcanol. Geotherm. Res., +,,, +.3 +0..