SGP/RL/C1 - Invalid liquid water channel data

On 20060906, the liquid water channel (LWC) was disabled due to the removal of its 
photomultiplier tube (PMT).  Consequently, the signals recorded for the LWC contain either zero 
or pure noise after that date.

Also, starting on 20070522, the LWC was populated with data from the T2 channel as a 
result of a slight reconfiguration of the data acquisition system.

On 4 March 2008 The LW channel photomultiplier tube was reinstalled in the Raman lidar. 
Effective 0000 UTC on 5 March 2008 the LW channel began producing valid liquid water data 
once again.

Do not use data from the LW channel between 20060906 and 20080304.

• Summed analog signal in the liquid water channel(liquid_analog_high)
• Number of photons counted in the liquid water channel(liquid_counts_high)