Problems with accelerometers

The 2003 San Simeon earthquake highlighted problems with the FBA-23s and Episensors at several BDSN sites. JRSC (FBA-23), MHC (FBA-23), WENL (FBA-23), and RFSB (Episensor) showed problems with the San Simeon recording (primilarly poor response to ground motions). Over the past year, we have continued our program to replace the older FBA-23s with Episensors as well as address other noise-related issues. Seven stations (FARB, JCC, MHC, WENL, YBH, HUMO) have been upgraded and a new one (GASB) installed.