benchmark, date, observer, organization, receiver, receiver_sn, receiver_type, antenna, antenna_sn, dome, height (m), slant height (m), interval, first_observation (s)
 helo, 1999-09-15,  GWB ,  USGS ,  ASHTECH,  O4597 ,  Z-XII3 CC00,  ASH701945.02B,  CR619992801,  NONE, 1.252, 1.3008, 30, 1610
 helo, 1999-09-19,  GWB ,  USGS ,  ASHTECH,  O4597 ,  Z-XII3 CC00,  ASH701945.02B,  CR619992801,  NONE, 1.3277, 1.3757, 30, 153330
 helo, 2003-06-28,  SAH ,  USGS ,  ASHTECH,  LP019992804 ,  Z-XII3 CD00,  ASH701945E_M,  CR620022602,  NONE, 1.4399, 1.487, 30, 1610
 helo, 2003-07-03,  WRT ,  USGS ,  ASHTECH,  LP019992803 ,  Z-XII3 CD00,  ASH701945B_M,  CR519993706,  NONE, 1.3925, 1.44, 30, 161230
 helo Helo_stmpd_HELO12H_W, 2008-02-24,  CHS ,  USGS ,  ASHTECH,  ZE1200526043 ,  Z-X ZE21,  ASH700936D_M,  CR14333,  NONE, 0.7833, 0.8399, 30, 162530
 helo Helo_stmpd_HELO12H_W, 2008-02-25,  CHS ,  USGS ,  ASHTECH,  ZE1200526043 ,  Z-X ZE21,  ASH700936D_M,  CR14333,  NONE, 0.7833, 0.8399, 30, 0
 helo Helo_stmpd_HELO12H_W, 2008-02-26,  CHS ,  USGS ,  ASHTECH,  ZE1200526043 ,  Z-X ZE21,  ASH700936D_M,  CR14333,  NONE, 0.7833, 0.8399, 30, 0
 helo HELO12H_W558+73.34PO, 2008-09-07,  CHS ,  USGS ,  ASHTECH,  ZE120023208 ,  Z-X ZE21,  ASH701945B_M,  CR619992805,  NONE, 1.4187, 1.4659, 30, 15350
 helo HELO12H_W558+73.34PO, 2008-09-11,  JLS ,  USGS ,  ASHTECH,  ZE1200331006 ,  Z-X ZE21,  ASH700936D_M,  CR14330,  NONE, 1.2491, 1.2979, 30, 141515