TWP/VCEIL/C3 - low receiver sensitivity

The ceilometer reported frequent receiver alarms. There are periods when the receiver 
sensitivity dropped to about 50%. The problem was corrected by replacing the instrument with 
a spare.

• Lowest cloud base height detected.(first_cbh)
• Vertical visibility(vertical_visibility)
• Aerosol volume backscattering coefficient at 355 nm(backscatter)
• SUM of detected and normalized backscatter(sum_backscatter)
• Second lowest cloud base height(second_cbh)
• Third cloud base height(third_cbh)
• Percentage of nominal factory setting (0 to 999%)(receiver_sensitivity)
• Altitude of highest signal(alt_highest_signal)
• Millivolts at internal ADC input (0 to 2500)(background_light)

TWP/MMCR/C3 - Reprocess: Reflectivity Calibration Problems

There was a problem with the reflectivity values being shifted 15-20 dBz less than what 
one might expect them to be.  The low noise amplifier (LNA) was damaged by lightning.  The 
LNA was replaced 20060718.

• First Order Estimate of Spectral Count Calibration(CalibrationConstant)
• Radar Constant(RadarConstant)
• Receiver Gain(RxGain)
• Receiver Sky Noise(SkyNoiseLevel)
• Minimum detectable reflectivity(MinimumDetectableReflectivity)
• Receiver 290K Level(Rx290KLevel)
• Receiver Cal Check Level(CalCheckLevel)

• Receiver Sky Noise(SkyNoiseLevel)
• Receiver Cal Check Level(CalCheckLevel)
• Minimum detectable reflectivity(MinimumDetectableReflectivity)
• Range Corrected Calibrated Power(RangeCorrectedPower)
• Receiver 290K Level(Rx290KLevel)
• MMCR Reflectivity(Reflectivity)
• Radar Constant(RadarConstant)
• Receiver Gain(RxGain)

TWP/SMET/C3 - Reprocess: Barometric Data Changed from hPa to kPa

Barometric pressure data was converted from hPa to kPa in order to standardize the 
measurement units among ARM sites and to conform to accepted standard units determined by the 
scientific community.

• Atmospheric pressure(atmos_pressure)