- 25: BPH, Site ASTER, Thu 13-Jun-1996 16:43:55 GMT, Krypton cal
Krypton #1133 was calibrated in the Thunder before
being shipped to Flatland. Below are the calibration
coefficients for the sensor. The pathlength was measured
to be 1.458 cm.
Vapor range V0 Kw
(g/m^3) (mv) (m^3/gcm)
2 - 19 2854 -0.142
2 - 9 2952 -0.145
8-19 2573 -0.137
The values for the 2-19 vapor range have been entered
into $ASTER/cal_files/krypton1133
- 38: BPH, Site 3, Fri 14-Jun-1996 22:22:38 GMT, Fixed BPH
The BPH s/n #40 was installed on the station and the earlier problem
was fixed.
The problem was 2-fold:
- ATI A/D connector's power ground pin was pushed up (and was
a bitch to get down without the proper tool).
- The Limo connector on the BPH housing appears to also to be
making poor contact. A little bit of reseating and wiggling
seemed to do it.
I cannot say for sure whether or not the BPH will stay up. The readings
when we left were consistent with the TRH, but not exact: about 5% higher
in RH.
- 58: BPH, Site 3, Tue 18-Jun-1996 15:47:33 GMT, Bandpass hygrometer errors
bph at station 3 reporting bad data during the daytime, June 17.
This sensor already appears to be more sensitive to radiative
heating than stations 1 and 2, but from 1500-2100 gmt, June 17,
the temperature was about 10 degC too high. From 1400-1600, the
RH was 90-100%, while the other sensors reported 70-80%.
bph at station 1 has a tendency to saturate around 98% RH at night.
This occured on the nights of June 16 and 17.
- 75: BPH, Site 3, Fri 21-Jun-1996 21:05:37 GMT, Bandpass hygrometer temperature (and RH)
The bandpass hygrometer temperature at site 3 appears to be about 1
degC too high during the day, as though it had a radiation heating
problem. Steve suggests checking the whether the inner shield is
properly recessed (about 1 inch) relative to the outer shield or
whether the prt is touching the gaurd. The temperatures at sites
1 and 2 appear to have the expected diurnal cycle relative to the
hygrothermometers which are at 2m compared to (3.2, 4.5, 3.2)m for
the bandpass hygrometers.
We also think that we have the wrong coefficients loaded for the
bandpass RH calibrations at all three sites.
- 96: BPH, Site 3, Mon 24-Jun-1996 19:55:35 GMT, Swapped bandpass hygrometers at stations 1 and 3
John is swapping the bandpass hygrometers at stations 1 and 3 today,
in order to isolate the problem with the bph at station 3. He removed
the bph at station 1 (#23) and we mounted it at station 3, entering
the appropriate calibration coefficients in EVE.
At that time we found the inner shield of the hygrothermometer
extending about 1.5" below the beehive. John replaced it, but found
that one or more of the screws that hold it in place had stripped their
threads in the Delrin outer cylinder.
John disassembled the bph from station 3 (#40) and looked at the
sensing elements of the 50Y, but there was no apparent problem.
John will install #40 on station 1 later this afternoon.
- 109: BPH, Site 1, Tue 25-Jun-1996 23:48:16 GMT, Station Visit: BPH #23 installed, ETI test, Vbatt check
Station 1 Visit: 22:05-23:35Z, 96/06/25, JD177
BPH #23 installed once again.
It works and the correct config was reinstalled and confirmed.
Crop Heights: I'll repeat this in another message, but...
Nominal corn to the SW: 35". Peak 42". Min 30"
Power Monitor System: Logged Elsewhere
ETI Test: logged elsewhere.
- 149: BPH, Site 3, Sun 30-Jun-1996 19:12:27 GMT, BPH temperature still high on station 3
The BPH temperature at station 3 is still high.
The fan showed no obvious signs of problems. I will
replace the fan with a new one. I may run a comparison
test with the BPH mounted next to the TRH.
- 156: BPH, Site 3, Sun 30-Jun-1996 21:15:58 GMT, station 3 BPH moved
station visit 20:00 - 20:45 GMT
I moved the BPH down to the TRH crossarm. The sensor
is looking into the beehive about 12" away. At this time
it does not look like anything has been gained. I will change
the fan tomorrow.
- 159: BPH, Site 3, Mon 01-Jul-1996 16:34:33 GMT, BPH at station 3
visit time: 15:00 - 16:00 GMT
The BPH at station 3 is much better. I replaced the fan and
taped up the connection between the 50Y and the limo. There were
exposed wires. The BPH was then mounted at the 2m height and
monitored for awhile. The temperature readings were about 0.3
degrees lower than the TRH. The sensor was then mounted on the
ATI boom.
I am not totally convinced the problem was the fan. If time
permits I may put the orginal fan back to try an isolate the
source of the problem.
- 302: BPH, Site 1, Fri 19-Jul-1996 18:32:14 GMT, BPH sensor cleaned
The sensors themselves looked pretty clean, but I washed the humidity sensor
with tap water anyway. There were a lot of webs/seed strands in the plastic
guard that I also removed.
- 303: BPH, Site 1, Fri 19-Jul-1996 18:34:03 GMT, cleaned krypton
Because we have been seeing increasing humidity differences from the krypton,
I cleaned it in the same big visit to PAM1 today. The tissue came off a bit
dirty.
This appears to have restored the signal bias.
- 385: BPH, Site 1, Tue 30-Jul-1996 02:45:06 GMT, problem with aster rh2o
If I've followed the code correctly, ASTER is using a DEFAULT pressure of
800 mb to compute rh2o from t and rh from the bandpass hygrometer (since
it doesn't have a real pressure in the data stream). This probably is
the cause of the differences between rh2o:rh2o from pam1 and adam1.