The data from the Licor at 16 meters went bad on Oct 2, while our system was not reachable over the network.
http://www.eol.ucar.edu/isf/projects/BEACHON_SRM/isfs/qcdata/plots/2011/10/02/co2_20111002.png
The ldiag value went from the typical 248-255 range to 216, a jump downwards of 32:
http://www.eol.ucar.edu/isf/projects/BEACHON_SRM/isfs/qcdata/plots/2011/10/02/licor_20111002.png
This CWEX11 logbook entry has some information about the licor diagnostic value:
32=2^5, so it looks like bit 5 in the diagnostic value has become 0, which is a problem in the PLL/chopper motor. According to the manual:
PLL - Phase Lock Loop offset, indicates the status of the chopper motor. If not OK, there may be a problem with the chopper motor in the sensor head.
I will look at some high rate values of ldiag to make sure bit 5 is 0.