SGP/MMCR/C1 - Noise Level Shift

The MMCR experienced an extreme noise level shift.  Since we were not on-site to 
troubleshoot this problem, we are unable to pinpoint its actual cause but rebooting the system 
returned the MMCR to normal operation.  We speculate that the problem is with one of the 
receiver protection switches latching in an isolated position.  If this is what is 
happening, the problem can be in the switch itself, its driver, or the timing circuitry 
controlling the driver.  This error happens occasionally at all MMCRs but is more frequent at the 
SGP radar.

Do not use the data during this period.

• Number of Code Bits(NumCodeBits)
• base time in epoch(base_time)
• Receiver Mode(ReceiverMode)
• Current Receiver Number(ReceiverNumber)
• Minimum detectable reflectivity(MinimumDetectableReflectivity)
• Receiver 290K Level(Rx290KLevel)
• Inter-Pulse Period(InterPulsePeriod)
• Number of Receiver(NumReceivers)
• Max. height of clutter removal(ClutterHeight)
• -180.0 - +180.0(alt)
• Circular Depolarization Ratio(CircularDepolarizationRatio)
• Delay to First Range Gate(StartGateDelay)
• time_in_seconds_since_volume_start(time)
• Receiver Cal Check Time Stamp(CalCheckTime)
• Time associated with hourly averaged values(TimeAvg)
• North Latitude(lat)
• Average Noise Level (S/N<0)(AvgNoiseLevel)
• Power (uncalibrated)(Power)
• Pulse Width(PulseWidth)
• TWT Status Code, details forthcoming from MMCR vendor(TWTStatusCode)
• radar mode char identifier(ModeDescription)
• lon(lon)
• Gate Spacing(GateSpacing)
• Radar Constant(RadarConstant)
• Receiver Cal Check Level(CalCheckLevel)
• MMCR Mean Doppler Velocity(MeanDopplerVelocity)
• Mean Noise Level(NoiseLevel)
• Operating Set for this Record(ModeNum)
• Number of Spectral Averages(NumSpectralAverages)
• MMCR Spectral Width(SpectralWidth)
• Number of Points in FFT(NumFFT)
• Data Quality Status(DataQualityStatus)
• Receiver Sky Noise(SkyNoiseLevel)
• Number of Coherent Integrations(NumCoherentIntegrations)
• Range Corrected Calibrated Power(RangeCorrectedPower)
• Time offset from base_time(time_offset)
• Windowing ON-OFF Status(WindowingONOFF)
• Reflectivity(Reflectivity)
• DC Filtering ON-OFF Status(DCFilterONOFF)
• Number of Range Gates(NumHeights)
• Range Heights (center of radar sample volume)(heights)
• RadarWaveLength(m) / [4 * InterPulsePeriod(s) * NumCoherentIntegrations](NyquistVelocity)
• Signal to Noise Ratio(SignalToNoiseRatio)
• Peak tranmitted power, averaged over the course of the hour(PeakTransmittedPowerAvg)
• Receiver Cal Time Stamp(RxCalTimeStamp)
• Receiver Gain(RxGain)

• Receiver Gain(RxGain)
• base time in epoch(base_time)
• Time offset from base_time(time_offset)
• Number of Range Gates(NumHeights)
• lon(lon)
• DC Filtering ON-OFF Status(DCFilterONOFF)
• First Order Estimate of Spectral Count Calibration(CalibrationConstant)
• Pulse Width(PulseWidth)
• Azimuth(Azimuth)
• Circular Depolarization Ratio(CircularDepolarizationRatio)
• Mean Noise Level(NoiseLevel)
• Inter-Pulse Period(InterPulsePeriod)
• Receiver Mode(ReceiverMode)
• Windowing ON-OFF Status(WindowingONOFF)
• Receiver Sky Noise(SkyNoiseLevel)
• Power (uncalibrated)(Power)
• Range Heights (center of radar sample volume)(Heights)
• Receiver Cal Time Stamp(RxCalTimeStamp)
• Operating Set for this Record(ModeNum)
• Range Corrected Calibrated Power(RangeCorrectedPower)
• MMCR Spectral Width(SpectralWidth)
• Receiver Cal Check Time Stamp(CalCheckTime)
• Elevation(Elevation)
• Number of Spectral Averages(NumSpectralAverages)
• Gate Spacing(GateSpacing)
• Number of Receiver(NumReceivers)
• Delay to First Range Gate(StartGateDelay)
• Receiver 290K Level(Rx290KLevel)
• Minimum detectable reflectivity(MinimumDetectableReflectivity)
• RadarWaveLength(m) / [4 * InterPulsePeriod(s) * NumCoherentIntegrations](NyquistVelocity)
• Max. height of clutter removal(ClutterHeight)
• Radar Constant(RadarConstant)
• Number of Code Bits(NumCodeBits)
• Receiver Cal Check Level(CalCheckLevel)
• Spectra(Spectra)
• MMCR Mean Doppler Velocity(MeanDopplerVelocity)
• Average Noise Level (S/N<0)(AvgNoiseLevel)
• North Latitude(lat)
• Data Quality Status(DataQualityStatus)
• Current Receiver Number(ReceiverNumber)
• radar mode char identifier(ModeDescription)
• Reflectivity(Reflectivity)
• Signal to Noise Ratio(SignalToNoiseRatio)
• Number of Coherent Integrations(NumCoherentIntegrations)
• Number of Points in FFT(NumFFT)
• -180.0 - +180.0(alt)