TWP/VCEIL/C2 - Receiver failure

The receiver failed and the instrument was replaced.  Data during the specified period are 
not valid.

• Vertical visibility(vertical_visibility)
• Aerosol volume backscattering coefficient at 355 nm(backscatter)
• Lowest cloud base height detected(first_cbh)
• Second lowest cloud base height(second_cbh)
• Millivolts at internal ADC input (0 to 2500)(background_light)
• Third cloud base height(third_cbh)
• Altitude of highest signal(alt_highest_signal)
• Sum of detected and normalized backscatter(sum_backscatter)