                             rx                  tx

1252075500: 2.2150000000e+01 7.7900000000e+00
1252075760: 2.5814000000e+02 6.1660000000e+01
1252075770: 3.3962000000e+02 1.5922000000e+02
1252075780: 2.8069000000e+02 4.2576000000e+02
1252075790: nan nan
1252075800: nan nan
