  Vaisala Combined Pressure, Humidity, and Temperature Transmitter
  Model: PTU307
  Serial Number: J1620011
  Location: forward mast

  Example data lines:
    met_ptu307  2014-12-11T22:57:50.4649Z  N     0 P=  1016.8 hPa   T= 24.5 'C RH= 68.0 %RH

  Field Descriptions:
    Logger ID
    Time Stamp [UTC]
    Transmitter status [7 character field, for example:
        N     0    no heating
        h   115    probe heating active, power 115/255
        H 159.0    purge heating active, temperature 159C
        S 115.0    purge cooling active, temperature 115C
        X  95.0    sensor heating active, temperature 95C ]
    Atmospheric pressure[hPa]
    Air Temperature[C]
    Relative Humidity[%]