benchmark, date, observer, organization, receiver, receiver_sn, receiver_type, antenna, antenna_sn, dome, height (m), slant height (m), interval, first_observation (s)
 twvl TWVL_2005_USGS, 2006-11-17,  GDH ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH700936D_M,  CR14244,  NONE, 0.5992, 0.6618, 30, 0
 twvl TWVL_2005_USGS, 2006-11-18,  GDH ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH700936D_M,  CR14244,  NONE, 0.5992, 0.6618, 30, 0
 twvl TWVL_2005_USGS, 2006-11-19,  GDH ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH700936D_M,  CR14244,  NONE, 0.5992, 0.6618, 30, 0
 twvl TWVL_2005_USGS, 2006-11-20,  GDH ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH700936D_M,  CR14244,  NONE, 0.5992, 0.6618, 30, 0
 twvl TWVL_2005_USGS, 2006-11-21,  GDH ,  USGS ,  ASHTECH,  ZE1200331018 ,  Z-X ZE21,  ASH700936D_M,  CR14244,  NONE, 0.5992, 0.6618, 30, 0
 twvl TWVL_2005_USGS, 2008-07-08,  JMS ,  USGS ,  ASHTECH,  ZE120023204 ,  Z-X ZE21,  ASH701945B_M,  CR519993706,  NONE, 0.673, 0.7328, 30, 171330
 twvl TWVL_2005_USGS, 2008-07-09,  JMS ,  USGS ,  ASHTECH,  ZE120023204 ,  Z-X ZE21,  ASH701945B_M,  CR519993706,  NONE, 0.673, 0.7328, 30, 0
 twvl TWVL_2005_USGS, 2008-07-10,  JMS ,  USGS ,  ASHTECH,  ZE120023204 ,  Z-X ZE21,  ASH701945B_M,  CR519993706,  NONE, 0.673, 0.7328, 30, 0
 twvl TWVL_2005_USGS, 2008-07-11,  JMS ,  USGS ,  ASHTECH,  ZE120023204 ,  Z-X ZE21,  ASH701945B_M,  CR519993706,  NONE, 0.673, 0.7328, 30, 0
 twvl TWVL_2005_USGS, 2009-08-11,  JMS ,  USGS ,  ASHTECH,  ZE1200331017 ,  Z-X ZE210,  ASH701945B_M,  CR619992805,  NONE, 0.5982, 0.6609, 30, 17370
 twvl TWVL_2005_USGS, 2009-08-12,  JMS ,  USGS ,  ASHTECH,  ZE1200331017 ,  Z-X ZE210,  ASH701945B_M,  CR619992805,  NONE, 0.5982, 0.6609, 30, 0
 twvl TWVL_2005_USGS, 2010-06-15,  JMS ,  USGS ,  ASHTECH,  ZE1200331017 ,  Z-X ZE210,  ASH701945E_M,  CR620022601,  NONE, 0.5584, 0.6228, 15, 18210
 twvl TWVL_2005_USGS, 2010-06-16,  JMS ,  USGS ,  ASHTECH,  ZE1200331017 ,  Z-X ZE210,  ASH701945E_M,  CR620022601,  NONE, 0.5584, 0.6228, 15, 0
 twvl TWVL_2005_USGS, 2010-06-17,  JMS ,  USGS ,  ASHTECH,  ZE1200331017 ,  Z-X ZE210,  ASH701945E_M,  CR620022601,  NONE, 0.5584, 0.6228, 15, 0
 twvl TWVL_2005_USGS, 2010-06-18,  JMS ,  USGS ,  ASHTECH,  ZE1200331017 ,  Z-X ZE210,  ASH701945E_M,  CR620022601,  NONE, 0.5584, 0.6228, 15, 0
 twvl TWVL_2005_USGS, 2018-09-11,  ELP ,  USGS ,  JAVAD,  00620 ,  TRE_G3TH SIGMA3.6.9,  JAVRINGANT_DM,  00488,  NONE, 0.7504, 0.8078, 15, 183515
 twvl TWVL_2005_USGS, 2018-09-12,  ELP ,  USGS ,  JAVAD,  00620 ,  TRE_G3TH SIGMA3.6.9,  JAVRINGANT_DM,  00488,  NONE, 0.7504, 0.8078, 15, 0
 twvl TWVL_2005_USGS, 2018-09-13,  ELP ,  USGS ,  JAVAD,  00620 ,  TRE_G3TH SIGMA3.6.9,  JAVRINGANT_DM,  00488,  NONE, 0.7504, 0.8078, 15, 0