Data Quality Reports for Session: 104611 User: cadyp Completed: 03/02/2007

TABLE OF CONTENTS

DQR IDSubjectData Streams Affected
D000308.1SGP/SONDE - Questionable absolute pressuressgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1
D000308.2SGP/SONDE - Questionable absolute pressuressgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1
D000625.1SGP/SONDE/C1 - Operator used wrong calibration tapesgpsondeC1.00, sgpsondeC1.a0, sgpsondeC1.a1, sgpsondewrpnC1.00, sgpsondewrpnC1.a0,
sgpsondewrpnC1.a1, sgpsondewndcalcC1.c1
D000801.2SGP/SONDE/C1 - Incorrect absolute pressuresgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1, sgpsondewndcalcC1.c1
D990124.2SGP/SONDE - Dry bias in sonde RHsgpsondeB1.00, sgpsondeB1.a0, sgpsondeB1.a1, sgpsondeB4.00, sgpsondeB4.a0, sgpsondeB4.a1,
sgpsondeB5.00, sgpsondeB5.a0, sgpsondeB5.a1, sgpsondeB6.00, sgpsondeC1.00,
sgpsondeC1.a0, sgpsondeC1.a1, DsgpsondeB1.00, DsgpsondeB1.a0, DsgpsondeB1.a1, DsgpsondeB4.00,
DsgpsondeB4.a0, DsgpsondeB4.a1, DsgpsondeB5.00, DsgpsondeB5.a0, DsgpsondeB5.a1,
DsgpsondeC1.00, DsgpsondeC1.a0, DsgpsondeC1.a1, sgpsondeptuC1.00, DsgpsondeptuB1.00,
DsgpsondeptuB4.00, DsgpsondeptuB5.00, DsgpsondeptuB6.00, DsgpsondeptuC1.00, sgpsondewnpnB1.a0,
sgpsondewnpnB1.a1, sgpsondewnpnB4.a0, sgpsondewnpnB4.a1, sgpsondewnpnB5.a0,
sgpsondewnpnB5.a1, sgpsondewnpnB6.a0, sgpsondewnpnB6.a1, sgpsondewnpnC1.a0, sgpsondewnpnC1.a1,
sgpsondewnprC1.a0, sgpsondewnprC1.a1, sgpsondewrpnB1.00, sgpsondewrpnB1.a0,
sgpsondewrpnB1.a1, sgpsondewrpnB4.00, sgpsondewrpnB4.a0, sgpsondewrpnB4.a1, sgpsondewrpnB5.00,
sgpsondewrpnB5.a0, sgpsondewrpnB5.a1, sgpsondewrpnB6.00, sgpsondewrpnB6.a0,
sgpsondewrpnB6.a1, sgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1, sgpsondewrprB1.00,
sgpsondewrprB1.a0, sgpsondewrprB1.a1, sgpsondewrprB4.00, sgpsondewrprB4.a0,
sgpsondewrprB4.a1, sgpsondewrprB5.00, sgpsondewrprB5.a0, sgpsondewrprB5.a1, sgpsondewrprC1.00,
sgpsondewrprC1.a0, sgpsondewrprC1.a1, DsgpsondeptucalcB1.c1, DsgpsondeptucalcB4.c1,
DsgpsondeptucalcB5.c1, DsgpsondeptucalcC1.c1, DsgpsondenogcwrpnB1.c1, DsgpsondenogcwrpnB4.c1,
DsgpsondenogcwrpnB5.c1, DsgpsondenogcwrpnC1.c1, DsgpsondenogcptucalcB1.c1,
DsgpsondenogcptucalcB4.c1, DsgpsondenogcptucalcB5.c1, DsgpsondenogcptucalcC1.c1


DQRID : D000308.1
Start DateStart TimeEnd DateEnd Time
03/03/2000232803/04/20000051
Subject:
SGP/SONDE - Questionable absolute pressures
DataStreams:sgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1
Description:
The sonde surface pressure reading was considerably higher than the
corresponding THWAPS pressure (988.0 hPa vs 982.3 hPa).  The sonde
readings are consistent during the sounding, however, suggesting that
this is not a case of a pressure jump at launch but one of sensor offset.
This problem will only affect those who use the absolute pressure values.
The file altitudes, which are based on the relative pressure changes
from the surface, should be fine.
Measurements:sgpsondewrpnC1.a0:
  • pressure at constant pressure surface(pres)
sgpsondewrpnC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrpnC1.a1:
  • pressure at constant pressure surface(pres)

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DQRID : D000308.2
Start DateStart TimeEnd DateEnd Time
03/04/2000022903/04/20000359
Subject:
SGP/SONDE - Questionable absolute pressures
DataStreams:sgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1
Description:
The sonde surface pressure reading was considerably higher than the
corresponding THWAPS pressure (992.9 hPa vs 983.0 hPa).  The sonde
readings are consistent during the sounding, however, suggesting that
this is not a case of a pressure jump at launch but one of sensor offset.
This problem will only affect those who use the absolute pressure values.
The file altitudes, which are based on the relative pressure changes
from the surface, should be fine.
Measurements:sgpsondewrpnC1.a0:
  • pressure at constant pressure surface(pres)
sgpsondewrpnC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrpnC1.a1:
  • pressure at constant pressure surface(pres)

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DQRID : D000625.1
Start DateStart TimeEnd DateEnd Time
06/23/2000233006/24/20000100
Subject:
SGP/SONDE/C1 - Operator used wrong calibration tape
DataStreams:sgpsondeC1.00, sgpsondeC1.a0, sgpsondeC1.a1, sgpsondewrpnC1.00, sgpsondewrpnC1.a0,
sgpsondewrpnC1.a1, sgpsondewndcalcC1.c1
Description:
It appears as if the operators had a problem with the original sounding
and launched a second radiosonde.  Apparently they used the calibration
tape that came with the first radiosonde (serial number 943156405) in
place of the one that was correct for the second radiosonde (sn 943156406)
and all the data are bad after the first sample (surface values).
Measurements:sgpsondewrpnC1.a0:
  • pressure at constant pressure surface(pres)
  • Relative humidity scaled, by total column amount from MWR(rh)
  • surface wind speed(wspd)
  • Ascent Rate(asc)
  • Dry-Bulb Temperature(tdry)
  • east longitude for all the input platforms.(lon)
  • Wind Status(wstat)
  • Surface dew point temperature(dp)
  • north latitude for all the input platforms.(lat)
  • altitude above sea levelaltunits(alt)
  • Wind Direction(deg)
  • Time offset of tweaks from base_time(time_offset)
  • Time offset from base_time(base_time)
sgpsondeC1.a0:
  • altitude above sea levelaltunits(alt)
  • Surface dew point temperature(dp)
  • Ascent Rate(asc)
  • Dry-Bulb Temperature(tdry)
  • Wind Status(wstat)
  • Relative humidity scaled, by total column amount from MWR(rh)
  • surface wind speed(wspd)
  • north latitude for all the input platforms.(lat)
  • Time offset from base_time(base_time)
  • east longitude for all the input platforms.(lon)
  • pressure at constant pressure surface(pres)
  • Time offset of tweaks from base_time(time_offset)
  • Wind Direction(deg)
sgpsondewrpnC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewndcalcC1.c1:
  • W-to-E Component of wind, calculated(u_wind_calc)
  • east longitude for all the input platforms.(lon)
  • north latitude for all the input platforms.(lat)
  • Flags for input v_wind values(v_wind_flags)
  • Flags for input u_wind values(u_wind_flags)
  • Time offset from base_time(base_time)
  • S-to-N Component of Wind, calculated(v_wind_calc)
  • pressure at constant pressure surface(pres)
  • Time offset of tweaks from base_time(time_offset)
  • altitude above sea levelaltunits(alt)
sgpsondeC1.a1:
  • altitude above sea levelaltunits(alt)
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Ascent Rate(asc)
  • Time offset from base_time(base_time)
  • surface wind speed(wspd)
  • model zonal wind velocity(u_wind)
  • Wind Status(wstat)
  • Wind Direction(deg)
  • Surface dew point temperature(dp)
  • pressure at constant pressure surface(pres)
  • east longitude for all the input platforms.(lon)
  • Time offset of tweaks from base_time(time_offset)
  • north latitude for all the input platforms.(lat)
  • Dry-Bulb Temperature(tdry)
  • model meridional wind velocity(v_wind)
sgpsondeC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrpnC1.a1:
  • Ascent Rate(asc)
  • Relative humidity scaled, by total column amount from MWR(rh)
  • altitude above sea levelaltunits(alt)
  • Wind Direction(deg)
  • north latitude for all the input platforms.(lat)
  • east longitude for all the input platforms.(lon)
  • model meridional wind velocity(v_wind)
  • Time offset of tweaks from base_time(time_offset)
  • Wind Status(wstat)
  • pressure at constant pressure surface(pres)
  • model zonal wind velocity(u_wind)
  • Dry-Bulb Temperature(tdry)
  • Time offset from base_time(base_time)
  • Surface dew point temperature(dp)
  • surface wind speed(wspd)

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DQRID : D000801.2
Start DateStart TimeEnd DateEnd Time
07/25/2000053307/25/20000724
Subject:
SGP/SONDE/C1 - Incorrect absolute pressure
DataStreams:sgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1, sgpsondewndcalcC1.c1
Description:
The surface pressure (983.5 hPa) reported by this radiosonde (sn 94315713)
is substantially higher than that reported by the THWAPS (~977) or by the
sondes used in the previous and following soundings (976.6, 977.3).  This
may be a calibration problem or a mechanic problem on launch.  The pressure
values reported in the remainder of the sounding are consistent with the
reported surface pressure, so the altitudes should be correct.  The
absolute pressure values may be high by about 5 hPa.
Measurements:sgpsondewrpnC1.a0:
  • pressure at constant pressure surface(pres)
sgpsondewrpnC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewndcalcC1.c1:
  • pressure at constant pressure surface(pres)
sgpsondewrpnC1.a1:
  • pressure at constant pressure surface(pres)

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DQRID : D990124.2
Start DateStart TimeEnd DateEnd Time
05/27/1992000005/31/20022359
Subject:
SGP/SONDE - Dry bias in sonde RH
DataStreams:sgpsondeB1.00, sgpsondeB1.a0, sgpsondeB1.a1, sgpsondeB4.00, sgpsondeB4.a0, sgpsondeB4.a1,
sgpsondeB5.00, sgpsondeB5.a0, sgpsondeB5.a1, sgpsondeB6.00, sgpsondeC1.00,
sgpsondeC1.a0, sgpsondeC1.a1, DsgpsondeB1.00, DsgpsondeB1.a0, DsgpsondeB1.a1, DsgpsondeB4.00,
DsgpsondeB4.a0, DsgpsondeB4.a1, DsgpsondeB5.00, DsgpsondeB5.a0, DsgpsondeB5.a1,
DsgpsondeC1.00, DsgpsondeC1.a0, DsgpsondeC1.a1, sgpsondeptuC1.00, DsgpsondeptuB1.00,
DsgpsondeptuB4.00, DsgpsondeptuB5.00, DsgpsondeptuB6.00, DsgpsondeptuC1.00, sgpsondewnpnB1.a0,
sgpsondewnpnB1.a1, sgpsondewnpnB4.a0, sgpsondewnpnB4.a1, sgpsondewnpnB5.a0,
sgpsondewnpnB5.a1, sgpsondewnpnB6.a0, sgpsondewnpnB6.a1, sgpsondewnpnC1.a0, sgpsondewnpnC1.a1,
sgpsondewnprC1.a0, sgpsondewnprC1.a1, sgpsondewrpnB1.00, sgpsondewrpnB1.a0,
sgpsondewrpnB1.a1, sgpsondewrpnB4.00, sgpsondewrpnB4.a0, sgpsondewrpnB4.a1, sgpsondewrpnB5.00,
sgpsondewrpnB5.a0, sgpsondewrpnB5.a1, sgpsondewrpnB6.00, sgpsondewrpnB6.a0,
sgpsondewrpnB6.a1, sgpsondewrpnC1.00, sgpsondewrpnC1.a0, sgpsondewrpnC1.a1, sgpsondewrprB1.00,
sgpsondewrprB1.a0, sgpsondewrprB1.a1, sgpsondewrprB4.00, sgpsondewrprB4.a0,
sgpsondewrprB4.a1, sgpsondewrprB5.00, sgpsondewrprB5.a0, sgpsondewrprB5.a1, sgpsondewrprC1.00,
sgpsondewrprC1.a0, sgpsondewrprC1.a1, DsgpsondeptucalcB1.c1, DsgpsondeptucalcB4.c1,
DsgpsondeptucalcB5.c1, DsgpsondeptucalcC1.c1, DsgpsondenogcwrpnB1.c1, DsgpsondenogcwrpnB4.c1,
DsgpsondenogcwrpnB5.c1, DsgpsondenogcwrpnC1.c1, DsgpsondenogcptucalcB1.c1,
DsgpsondenogcptucalcB4.c1, DsgpsondenogcptucalcB5.c1, DsgpsondenogcptucalcC1.c1
Description:
Vaisala has confirmed ARM findings of an apparent dry bias in the
relative humidity measured by RS-80H radiosondes.  The cause of
the dry bias is thought to be contamination of the humidity sensor
by volatile organic substances originating from some plastic parts
of the radiosonde.  The amount of contamination is a function of
the time between the date of sonde manufacture and its use.  All
RS-80H sondes manufactured before week 34 of 1998 will show this
bias.  After week 34 of 1998 Vaisala changed its packaging to
reduce, but not eliminate the contamination problem.

Starting with RS-80 radiosonde manufactured in late June 2000 Vaisala
enclosed the sensor boom in an inert plastic shield, thereby eliminating
the contamination that caused the dry bias.

Starting in May 2001 at the SGP, May 2002 at the TWP, and later 2002
at the NSA, ARM has moved to using RS-90 radiosondes.  These sondes
are not subject to the contaminatino that caused the dry bias.

Vaisala is in the process of developing an algorithm that can be 
used to estimate the correct RH from knowledge of the sonde age.
All of the ARM sounding data have sufficient metadata available
to apply the correction.

Additionally, ARM has funded a Science Team effort (Milosevich) to
develop a 'best' correction algorithm for the RS-80 radiosonde humidity
data.  When completed this algorithm will allow us to reprocess the
accumulated RS-80 data and produce a new data platform with what we
hope will be more accurate data.
Measurements:sgpsondeB4.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondeB5.00:
  • (Development raw data stream - documentation not supported)
sgpsondewrpnC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewnpnC1.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
DsgpsondeptuB6.00:
  • (Development raw data stream - documentation not supported)
DsgpsondenogcptucalcB1.c1:
  • (Development data stream - documentation not supported)
sgpsondewrpnB6.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
DsgpsondeptuC1.00:
  • (Development raw data stream - documentation not supported)
sgpsondewnprC1.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
DsgpsondenogcptucalcB5.c1:
  • (Development data stream - documentation not supported)
DsgpsondeptucalcC1.c1:
  • (Development data stream - documentation not supported)
sgpsondewnpnB4.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondeB6.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrprB4.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondeptuB1.00:
  • (Development raw data stream - documentation not supported)
DsgpsondenogcptucalcC1.c1:
  • (Development data stream - documentation not supported)
sgpsondewrpnC1.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrpnB1.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrprC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrpnB1.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrprB5.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondeB5.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrprB5.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondeC1.00:
  • (Development raw data stream - documentation not supported)
sgpsondewrprB1.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondeB1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondeptuC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondenogcptucalcB4.c1:
  • (Development data stream - documentation not supported)
DsgpsondeB1.a0:
  • (Development data stream - documentation not supported)
DsgpsondeC1.a1:
  • (Development data stream - documentation not supported)
DsgpsondeptucalcB5.c1:
  • (Development data stream - documentation not supported)
sgpsondewrprB1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrpnC1.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrpnB1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondeB1.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
DsgpsondeC1.a0:
  • (Development data stream - documentation not supported)
DsgpsondeB4.a1:
  • (Development data stream - documentation not supported)
DsgpsondeptuB4.00:
  • (Development raw data stream - documentation not supported)
sgpsondeB1.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrprB5.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondeC1.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewnpnB1.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrpnB6.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrprC1.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondeC1.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrprC1.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
DsgpsondeptuB5.00:
  • (Development raw data stream - documentation not supported)
sgpsondewrpnB5.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrprB4.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
DsgpsondeB1.a1:
  • (Development data stream - documentation not supported)
sgpsondeB5.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewnpnB6.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
DsgpsondeB5.a1:
  • (Development data stream - documentation not supported)
DsgpsondenogcwrpnB1.c1:
  • (Development data stream - documentation not supported)
sgpsondewrprB1.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrpnB5.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondeB4.a0:
  • (Development data stream - documentation not supported)
DsgpsondenogcwrpnB4.c1:
  • (Development data stream - documentation not supported)
DsgpsondeB5.a0:
  • (Development data stream - documentation not supported)
sgpsondewnpnB4.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewnprC1.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrpnB5.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewnpnB5.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
DsgpsondeB4.00:
  • (Development raw data stream - documentation not supported)
sgpsondewrpnB6.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
sgpsondewrprB4.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewnpnB1.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondeB4.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondeC1.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewrpnB4.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondenogcwrpnB5.c1:
  • (Development data stream - documentation not supported)
sgpsondewnpnC1.a0:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrpnB4.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
DsgpsondeB1.00:
  • (Development raw data stream - documentation not supported)
sgpsondeB4.a0:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
sgpsondewnpnB6.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewrpnB4.a1:
  • Surface dew point temperature(dp)
  • Relative humidity scaled, by total column amount from MWR(rh)
sgpsondewnpnB5.a1:
  • Relative humidity scaled, by total column amount from MWR(rh)
  • Surface dew point temperature(dp)
DsgpsondeptucalcB4.c1:
  • (Development data stream - documentation not supported)
DsgpsondenogcwrpnC1.c1:
  • (Development data stream - documentation not supported)
sgpsondeB5.00:
  • Raw data stream - documentation not supported(Raw data stream - documentation not supported)
DsgpsondeptucalcB1.c1:
  • (Development data stream - documentation not supported)

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