benchmark, date, observer, organization, receiver, receiver_sn, receiver_type, antenna, antenna_sn, dome, height (m), slant height (m), interval, first_observation (s)
 b428, 1999-09-16,  JTB ,  USGS ,  ASHTECH,  203 ,  Z-XII3 CD00,  ASH700936E_C,  CR16374,  NONE, 1.4508, 1.4978, 30, 15400
 b428, 1999-09-20,  JTB ,  USGS ,  ASHTECH,  203 ,  Z-XII3 CD00,  ASH700936E_C,  CR16374,  NONE, 1.4639, 1.5108, 30, 154630
 b428 B428_1984_NGS, 2003-06-21,  FFP ,  USGS ,  ASHTECH,  04600 ,  Z-XII3 CD00,  ASH700936D_M,  CR14244,  NONE, 1.1469, 1.1969, 30, 151030
 b428 B_428_1984, 2003-06-24,  SAH ,  USGS ,  ASHTECH,  LP019992804 ,  Z-XII3 CD00,  ASH701945E_M,  CR620022602,  NONE, 1.3975, 1.4449, 30, 16140
 b428 B428_1984_NGS, 2008-02-24,  JMS ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH701945B_M,  CR519993703,  NONE, 1.4318, 1.4789, 30, 17430
 b428 B428_1984_NGS, 2008-02-25,  JMS ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH701945B_M,  CR519993703,  NONE, 1.4318, 1.4789, 30, 0
 b428 B428_1984_NGS, 2008-02-26,  JMS ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH701945B_M,  CR519993703,  NONE, 1.5567, 1.6029, 30, 0
 b428 B428_1984_NGS, 2008-02-27,  JMS ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH701945B_M,  CR519993703,  NONE, 1.5567, 1.6029, 30, 0
 b428 B428_1984_NGS, 2008-02-28,  JMS ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH701945B_M,  CR519993703,  NONE, 1.5567, 1.6029, 30, 63130
 b428 B428_1984_NGS, 2008-02-29,  JMS ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH701945B_M,  CR519993703,  NONE, 1.5567, 1.6029, 30, 0
 b428 B428_1984_NGS, 2008-09-06,  CHS ,  USGS ,  ASHTECH,  ZE120023208 ,  Z-X ZE21,  ASH701945B_M,  CR619992805,  NONE, 1.4872, 1.5339, 30, 161330
 b428 B428_1984_NGS, 2008-09-09,  CHS ,  USGS ,  ASHTECH,  ZE120023208 ,  Z-X ZE21,  ASH701945B_M,  CR619992805,  NONE, 1.4902, 1.5369, 30, 154930