The binary data are available via anonymous FTP from the National Strong Ground Motion FTP-server:
https://ca.water.usgs.gov/nsmp/ in directory GEOS/CLG.
For further information on these recordings refer to USGS Open-File Report 84-697: Digital Recordings of Aftershocks of the May 2, 1983 Coalinga, California Earthquake; by C. S. Mueller, E. Sembera, and L. Wennerberg.
The GEOS Home Page is at /GEOS/geos.html
The URL of this page is /GEOS/CLG/coalinga.html
e-mail: glassmoyer@usgs.gov
or address:
Gary Glassmoyer
345 Middlefield Road M/S 977
Menlo Park, California 94025