These files are the data files for the PSAP (A11_*), CLAP (A13_*), reference or
dry nephelometer (S11), wet or humidified nephelometer(S12_*),condensation
particle counter (N61*) and cloud condensation nuclei counter (N11*). The X1_* file
has system pressures and temperatures, the X_* file has system messages that are
automated messages and messages sent by the site tech, the X3_* file has system
flow and RH values and the X5_* file has wind speed and direction.

An explaination of the file format is located on the NOAA ftp site at
www.esrl.noaa.gov/gmd/aero/software/aerosols/cpd2record.html .I went through the
files and color coded lines with variable names and variables that go into the
AOS datastream.