Description: | DQR No: Platform: CF BSRN
Subject: Instrument Field Test at BSRN CF Site
Date Submitted: 23 October 1995
Submitted By: Michael T. Rubes _X_ Instrument Mentor
___ EST Member
___ Science Team Member
___ Other
_____________________________
For questions or problems, please contact the ARM Experiment
Center at
509-375-6898 or via email at dqr@arm.gov.
Platform/Measurement:
What level data: (raw,a0,a1,b1,c1 etc):a0
What location was the data collected at: CF BSRN
Period of time in question
Begin Date 10/12/95 Time 20:45 (GMT)
End Date 10/13/95 Time 13:00 (GMT)
Data should be labeled:
___ questionable ___ All data fields affected
_X_ incorrect _X_ Only some data fields affected
___ wrong calibration
___ others
Discussion of Problem:
The radiometers in the BSRN Site at the CF are being tested to
determine the source of large nighttime offset values. The nominal
nighttime offsets are greater than -7 W/m^2. Recently, the Global
PSP has exhibited nighttime offsets of less than -50 W/m^2.
The test consists of shorting across the signal pins at the instru-
ment connector. This should result in a near zero voltage signal
at all times of the day.
Other observations/measurements impacted by this problem:
Only the CF BSRN PSPs, PIRs, and NIP will be influenced by this
problem.
No other instruments have been affected by this problem and the
test procedures will likewise, not affect any other systems.
Suggested Corrections of the Problem: (e.g. change calibration
factor and recompute, flag data with this comment, etc.)
The radiation data for the CF BSRN Site will be lost for the test
period. The period of the test should be flagged appropriately.
In the event that the test indicates that the instument is at fault,
then the suspect instrument(s) will be replaced.
In the event that the test indicates that the instument is not at fault,
then further testing will have to performed on the data line from the
instrument to the point of ingest.
Data Processing Notes Date
The instruments Global PSP and Diffuse PSP were down from:
1930 to 1955 GMT on 13 October, 1995 (JD286)
The calibration information for the instruments prior to that time:
Old DD/PSP serial # 29617F3 CF=9.72 uV/W/m^2
New DD/PSP serial # 30670F3 CF=9.17 uV/W/m^2
And the calibration information for the instruments installed on JD286:
Old DS/PSP serial # 14826F3 CF=9.16 uV/W/m^2
New DS/PSP serial # 30824F3 CF=8.773 uV/W/m^2
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___ Michael T. Rubes
__________/___\__________ NOAA/ARL/SRRB
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|___________________________| (303) 497-7316 (phone)
(303) 497-6546 (fax)
Surface Radiation Research Branch rubes@srrb.noaa.gov
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