benchmark, date, observer, organization, receiver, receiver_sn, receiver_type, antenna, antenna_sn, dome, height (m), slant height (m), interval, first_observation (s)
 spr4 Signal_Peak_Rm4_1990_, 1993-08-11,  JWK ,  USGS-CVO ,  ASHTECH LM-XII3,  007,  7A,  ASH700228D,  007,  NONE, 1.2228, 1.2719, 15, 211945
 spr4 Signal_Peak_Rm4_1990_, 1993-08-27,  JMS ,  USGS ,  ASHTECH LM-XII3,  2270,  7A,  ASH700228D,  2115,  NONE, 1.1175, 1.1679, 30, 214530
 spr4 Signal_Peak_Rm4_1990_, 1993-08-28,  JMS ,  USGS ,  ASHTECH LM-XII3,  2270,  7A,  ASH700228D,  2115,  NONE, 1.1175, 1.1679, 30, 300
 spr4 Signal_Peak_Rm4_1990, 2003-08-26,  JMS ,  USGS ,  ASHTECH,  04597 ,  Z-XII3 CD00,  ASH701945E_M,  CR620022605,  NONE, 1.1823, 1.2319, 30, 10
 spr4 Signal_Peak_Rm4_1990, 2003-08-27,  JMS ,  USGS ,  ASHTECH,  04597 ,  Z-XII3 CD00,  ASH701945E_M,  CR620022605,  NONE, 1.1823, 1.2319, 30, 10