Channel Data: Channel Sampling Rate Sensitivities BHZ 5 sps continuous 1.232e8 C/(m/s) (after 28 March, 1990) 1.340e8 C/(m/s) (before 28 March, 1990) 20 sps continuous after 30 May, 1991 BHN 5 sps continuous 1.256e8 C/(m/s) (after 28 March, 1990) 1.308e8 C/(m/s) (before 28 March, 1990) 20 sps continuous after 30 May, 1991 BHE 5 sps continuous 1.265e8 C/(m/s) 20 sps continuous after 30 May, 1991