FOOTPRINT92: SONIC Messages: 33 Entries..

Recalibration of T U of W sonic 
 
The T U of W sonic took a dive when it was being installed on the 100m station 
tower. It was taken into the apartment and straightened and then later 
micrometered. The following are the measurements. 
 
            PATH                     SEPARATION 
                               inches        centimeters 
                                 1       :       2.54 
            (Measured with special pointy metal inserts) 
      Yellow  -  Blue          7.8665          19.9809 
      Yellow  -  White         3.1660           8.0416 
      Yellow  -  Green         3.1265           7.9413 
      Yellow  -  Gray          7.1870          18.2550 
      Yellow  -  Orange        7.0890          18.0061 
      White   -  Grey          7.7905          19.7993 
      White   -  Green         3.1445           7.9870  
      White   -  Blue          7.1340          18.1204 
      White   -  Orange        7.0580          17.9273 
      Green   -  Orange        7.7180          19.6037 
      Green   -  Grey          7.1120          18.0645 
      Green   -  Blue          7.0620          19.9375 
      Blue    -  Grey          3.1350	        7.9629 
      Blue    -  Orange        3.2745           8.3172 
      Grey    -  Orange        3.1975           8.1216 
 
            (Measured with transducers reinserted)  
      Yellow  -  Blue          7.869           19.9873 
      White   -  Grey          7.818           19.8577 
      Green   -  Orange        7.729           19.6317 
 
 
These numbers were entered into the sonic geometry routine provided by Steve 
Oncley, and the following numbers entered into the calibration routine: 
 
 60.1124, 57.0984, 62.3198, 57.7271, 62.7474  
 
 
Steve Oncley provided the following angles from the dimensions we gave him 
over the phone: 
  60.1, 57.1, 62.3, 57.7, 62.7 
 

SONIC SPIKING: 
 
	The 5m ati, 250m, is spiking on 
the v component while the uw sonic at daisy, 
100m, is spiking. Hope to tune them later today. 
 

100m UW SONIC WORK: 
 
	Checked out signals on the uw 
sonic at daisy. Signals looked good. 
The b channel bottom(?) has a flaky polarity 
wire. So be careful if you play with it. 
Will monitor sensor. 
 

ATI at 250m: 
 
	Work is being down at the 250m tower 
to install the conditional sampler. This means 
that the ati sonic will be going up and down. 
 

NEW ANGLES FOR T uw SONIC: 
 
	The new angles for the T uw sonic 
have been entered in the calibration routine 
sonic_uw_4b.c. The new values are: 
   60.1, 57.1, 62.3, 57.7, 62.7 
 

LEVEL SENSORS ON ATI UNITS: 
 
	There has been no attempt at 
understanding the output from the ATI 
sonics. Maybe in the next day or two we 
will get around to it. 
 

UW SONIC @ DAISY: 
 
	For the last 1/2 hour I have been 
playing with the uw sonic at daisy, 100m. 
Some of the spiking during this time was 
generated by me. 
	The problem is with the receiver 
board for path c/top. There is not enough 
range in the gain and offset pots. I will 
try switching with another board. 
 

SONIC ZEROs: 
 
	This morning was dedicated to  
working on the sonics and getting another 
set of zeros. Therefore the data should be 
looked at with caution from 16:00Z to xxxZ. 
 

ZERO UW @ 175M: 
 
	Finished zeroing the uw 
sonic at 175m site about 3 minutes 
ago. Results provided below. Ther was no 
changes made to the sensor. 
 
channel		zero 
 
a (yb)		 -638 
b (gw)		  -19 
c (og)		  -41 
 
NOTE: these zeros have not been entered 
in the sonic_uw_4b.c routine 
 

UW SONIC @ 100M ZEROED: 
 
	Finish work on the uw sonic at 100m. 
Changed polarity on channel "a top". This work 
was completed at 19:50Z. Below are the zero 
information before work and after. 
 
before: 
	channel		zero 
 
	a (yb)		 175 
	b (gw)		-157 
	c (og)		 168 
 
 
after: 
 
	a (yb)		 32  
	b (gw)		-170 
	c (og)		 179 
 
NOTE: these zeros have not been entered in 
sonic_uw_4b.c routine. 
 

UW SONIC @ 100M STILL SPIKING: 
 
	The uw sonic at 100m is still 
spiking. At this point it is not known 
if the spiking is due to high winds. Right 
now the winds are light, 2 m/s, out of the southwest. 
There are no spikes. We will monitor the sensor. 
 

UW SONIC @ 100M: 
 
	The sonic at 100m looks good at  
higher winds, ~8 m/s. Will continue monitoring. 
 

SPIKING ON SONICS: 
 
	Some spiking going on on all sonics. 
Winds are pushing 8 to10 m/s. 
 

UW SONIC @ 100M SPIKING: 
 
	That sonic is spiking again! 
Winds are not to high. 
 

ATI.K sonic  at 250m: 
 
u channel output  was 9999 this morning and Tc was 
unreasonably large.  About 11 am PDT, Gordon checked 
the connector on the array and then we re-calibrated 
the sonic with the zero wind tubes.  This corrected  
the problem with the Tc channel, but the u axis  
would not calibrate.  Then about 1515 PDT, Tony  
reconnected that sonic to the conditional sampler 
and that appeared to correct the problem with the 
channel.  However when he disconnected the conditional 
sampler for a short period, the problem did not  
return (???). 
 
We also had a problem when turning on power on this 
sonic that it often required a  from an 
rserial connection to begin operating. 
 
 

ATI.K sonics recalibrated 
 
Recalibrated the ATI.K sonics at 50 and 
250m.  The 250m sonic calibrated okay with 
the observation that the mean v appeared to 
have a magnitude of ~ 20 cm/s.  The 50m 
sonic balked at calibration of the v component, 
but the others calibrated okay.  However on  
cockpit, the u component looks like noise 
centered on zero and the w component has 
an unrealistically large variance.  Only 
the v component looks believable. 
 
 

  250m ati u component started to show broad-band white noise after looking 
OK earlier this morning.  The problem was corrected yesterday by reconnecting 
the conditional sampler to the serial line from the sonic. 
 
  This was done again and reduced the noise on the u component to a "normal" 
looking signal. The conditional sampler will be taken back to Boulder, 
so we connected the conditional sampler serial input from the sonic, 
to the conditional sampler's output port on the serial breakout box.  This 
arrangement also seems to prevent the problem on the ati u component. 
  
 

atiK.50.10m sonic removed 
 
Checked the atiK.50.10m sonic with the 
oscilloscope and found that the u and  
w received pulses are very noisy and 
that v looked comparatively good. This 
corresponds to the observed quality of 
the measured winds. 
 
Gordon climbed the tower to determine 
whether loosening and tightening the 
sonic transducers would clean up the 
bad signals.  As he climbed the tower 
and it shook, the quality of the u 
received pulse varied quite noticeably, 
suggesting a poor connection.  Unscrewing 
and screwing the transducers back in did 
not improve the u component pulses and  
in the process the upper w transducer  
socket came loose from its wiring.   
The transducer  was very tightly screwed  
into its socket.  We took the sonic off  
the tower to return it to Boulder for 
repair and began to move the atiS sonic 
to 50m. 
 
 

  Placed atiS sonic on the 50 meter tower at 10m to replace the atiK 
sonic.  It is on ragwort serial channel 201, which had been reserved for 
a conditional sampler but never used.  Since there has been no data 
on that channel I did not start a new OPS.  The fast t and hygrometer 
are disconnected. 
 
 

Spiking on uw.100.10m on days 166, 167 
 
It appears from the variance and covariance 
plots that there is spiking on the uw sonic 
at 100m for days 166 and 167, as well as 
prior days. 
 
 

Recorded zero winds on atiS.50.10m 
this morning.  The results are in  
files  
FOOTPRINT92/zero_cals/atiS.50.u(v,w).169 
 
 

atiS.250.10m u axis went bonkers on JD 169 
from 0400 to 0800 and again around 1400 GMT. 
 
 

Replaced crystal on w2 axis of atiS.50.10m. 
 
Found that the inboard, top crystal of the 
w axis on the atiS.50.10m sonic was bad. 
Replaced it with a spare crystal.  The  
resulting signal was weak and there appears 
to be a large positive offset to the vertical 
wind component.  Collected a few minutes of 
data with the zero wind tube on the vertical 
axis from ~ 11:43 pm PDT to 11:45.  Find it 
in the archived data. 
 
 

Replaced atiK sonic at 50 m tower.  It is  
at the 1m level to moniter its performance. 
We had to adjust the amplification level on 
the u and w axes in order to get clean 
signals and a proper zero calibration. 
 
 

Moved 10m sonics at 100, 175, 250m towers 
down to 5m and moved atiK up to 5m.  Left 
atiS stored at 10m on 50m tower, but  
turned it off.  Began archiving data  
around 18:00 GMT, Monday, June 22. 
 
 

New sonic angles at 5m height: 
 
atiS.50.10m	296.6 deg 
atiK.50.5m	294.2 deg 
uw.100.5m	293.5 deg 
uw.175.5m	292.9 deg 
atiK.250.5m	295.8 deg 
 
After shooting the atiS.50.10m 
sonic and before shooting the 
atiK.50.5m sonic, we tightened 
the guy wires for the top of the 
50m tower. 
 
 

atiK.50.5m has stopped outputing wind 
data (output is -9999).  We will check 
in the morning to see whether it has 
recovered. 
 
 

Turned off atiK.50.5m at 20:11 PDT. 
 
  Assuming its problem is temperature, perhaps it will cool off 
while powered down. 
 
  Brian Lamb will turn it on before the sf6 release tonight. 
 

Fixed atiK.50.5m this morning by unscrewing and 
screwing back in the v component transducer on  
the right side facing the tower.  Recalibrated 
all three components. 
 
 

Sonic zeros 
 
Recorded sonic zero wind readings yesterday 
afternoon and this morning after lowering the 
sonics to the 1m level.  The data are in 
$ASTER/projects/FOOTPRINT92/zero_cals/file. 
 
atiK.50.5m:  Output from cshow to files  
atiK.50.(u,v,w).181.  Apparently only got 
good data for the u component.  The v  
component file is empty and the w component 
file is only -9999's.  We had previously 
adjusted one of the v component crystals on 
this array to fix a problem, and putting the 
zero wind tube on it may have knocked it out 
again! 
 
uw.100.5m:  Output from rserial to files 
uw.100.(yb,og,wg).181.  Data look good 
with the zeroed components having outputs 
less than 100 counts.   
 
uw.175.5m:  Output from rserial to files 
uw.175.(yb,og,wg).182.  og and wg data look good 
with the zeroed components having outputs 
less than 100 counts, but yb component had 
very large counts.   
 
atiK.250.5m:  Output from cshow to files 
atiK.250.(u,v,vw).182.  Data generally look 
good. 
 
 

Computed biases for uw sonics. 
 
Using data gathered on days 158, 160, and 180 with 
the zero wind tubes (see logbook entries 62 and 161), averages 
were computed for the uw zeroes. 
 
The zero wind data files are in directory 
	$ASTER/projects/FOOTPRINT92/zero_cals. 
The means and sd's were calculated with Splus function 
uw.zero.S in $ASTER/apps/sfun/sonics. 
 
Here are the results from that function for the a, b and c paths and s: 
 
Filename jday n med n sd    a med        a sd    b med        b sd    c med  
uw.100.og.158     2    0 -18891.5  739.465671 -30106.0  872.031704    166.0 
uw.100.og.160     2    0 -18830.0  771.887921 -29931.0  862.952025    179.0 
uw.100.og.181     2    0 -18877.0  766.500485 -30110.0  883.750534    176.0 
uw.100.wg.158     2    0 -18333.0  888.508256   -156.0    4.987600 -29715.0 
uw.100.wg.160     2    0 -18275.5 1270.996124   -170.0    2.615674 -29672.0 
uw.100.wg.181     2    0 -18003.5 1105.119859   -167.0    4.190566 -30048.0 
uw.100.yb.158     2    0    175.0    1.653627 -30361.0  967.193417 -28639.0 
uw.100.yb.160     2    0     32.0    2.918266 -30445.5  951.436930 -28645.5 
uw.100.yb.181     2    0     27.0    5.056332 -30176.0  994.640173 -28874.0 
uw.175.og.160     1    0 -19244.0  768.380930 -30522.0  886.014393    -41.0 
uw.175.og.182     1    0 -19219.0  762.714473 -30492.0  861.921993    -46.0 
uw.175.wg.160     1    0 -18442.0 1260.303476    -19.0    3.105111 -29583.0 
uw.175.wg.182     1    0 -18193.5 1185.146810    -19.0    4.095747 -29805.0 
uw.175.yb.160     1    0   -638.0    4.031459 -30329.0 1053.126334 -28758.5 
uw.175.yb.182     1    0 -19130.0 3600.000310 -30156.0  777.943373 -28910.0 
                     c sd    s med       s sd  
uw.100.og.158    9.657437 -21070.5 230.988857 
uw.100.og.160    3.591711 -21047.0 238.458963 
uw.100.og.181    5.843478  44468.0 238.877747 
uw.100.wg.158  924.216656 -20909.0 262.379806 
uw.100.wg.160 1410.626975 -20914.0 360.275509 
uw.100.wg.181 1184.101548  44708.0 312.329786 
uw.100.yb.158  968.201062 -28125.0   3.939563 
uw.100.yb.160  949.273152 -28158.0   3.966031 
uw.100.yb.181  990.355113  37496.0   8.511049 
uw.175.og.160    2.020809 -21207.0 244.366044 
uw.175.og.182    3.570118  44331.0 305.040397 
uw.175.wg.160 1379.984355 -21017.0 359.644870 
uw.175.wg.182 1283.226676  44664.5 467.635171 
uw.175.yb.160 1043.026925 -28416.0   1.879472 
uw.175.yb.182  773.379323  44312.0 640.878852 
 
The biases for a, b, c and s were then chosen to be: 
 
# FOOTPRINT92  uw sonic at 100 meters 
#	    azero bzero czero szero 
92 153 0000   175  -155   165   480 
92 160 1950    30  -170   180   410 
 
# FOOTPRINT92 uw sonic at 175 meters 
#	    azero bzero czero szero 
92 153 0000  -640   -20   -40   260 
 
These values are in files uw_sonic.1 and uw_sonic.2 on 
directory $ASTER/cal_files. 
 

Sonic data for FOOTPRINT92 
 
In late Oct and early Nov 93 the bias and tilt calculations for 
the FOOTPRINT92 sonics were carried out. 
 
The two functions used: 
		       fun.sonic.bias.plot 
                       fun.sonic.tilt.plot 
were composed by T. Horst and subsequently modified by G. Maclean. 
 
The programs are annotated and the default values for parameters 
displayed in the listing. Specified values for parameters which were  
utilized in this analysis were: 
            prop.corr = 65.75 for ops1 
              flagmax = 0.1  for ops1, 2, and 3 
	         wmax = 1.0  for ops1, 2, and 3 
 
Three configuration were specified during the FOOTPRINT92 deployment; 
 
  ops1 from jday 154:157  
    all sonics at 10m height on the four towers 
                  atiK.50.10m,  uw.100.10m,  uw.175.10m, atiK.250.10m 
 
    prop vane at 10 m at 50m station 
    prop azimuth not adjusted and a prop correction of 65.75 degrees needed 
 
 
  ops2 from jday 157:174 
  (This was an error as two separate sonics were deployed on the 50m tower,  
		  atiK from jday 157:163 
		  atiS from jday 167:174          
NB atiS.50.10m underwent a radical change on jday 171 at ???. See logbook 126 
   I have split the 167:174 into 167:170 and 172:174 
 
    all sonics at 10m height on  the four towers 
    jday 157:163  atiK.50.10m,  uw.100.10m,  uw.175.10m, atiK.250.10m 
	          ___________   
    jday 167:174  atiS.50.10m,  uw.100.10m,  uw.175.10m, atiK.250.10m 
                  -----------   
 
NB atiS.50.10m underwent a radical change on jday 171 at ?????? 
   I have split the 167:174 into 167:170 and 172:174 
 
    prop vane at 10 m at 50m station 
    prop azimuth properly adjusted and no prop correction needed 
 
 
  ops3 from jday 174:181  
    all sonics at 5m height on the four towers 
                  atiK.50.5m,   uw.100.5m,   uw.175.5m,  atiK.250.10m 
 
    prop vane at 5 m at 50m station 
    prop azimuth properly adjusted and no prop correction needed 
 
For all sonics for each ops the sonic azimuths were determined with 
a theodolite. These values of sonic.azm are the nominal values. The 
first step in processing the sonic data was to determine the true 
values for sonic.azm. This was done by comparing the difference 
between the propvane and the sonic as the value of the sonic's azimuth 
is varied. The value of the function, 
                 tot err = ((error in u)^2 + (errorin v)^2)^1/2 
was plotted as the assumed azimuth of the sonic, sonic.azm, was varied.  
A minimum in the curve corresponded o the true azimuth of the sonic. 
 
These true sonic.azm's were then used as input to the bias program which 
plots out wind  speeds given by the sonic and the prop for both u and v. 
The  gains and intercepts of these lines are given as: 
        	 u.gain, v.gain, u.off, and v.off. 
 
These gains and intercepts were then used as input to the tilt program 
which calculates for each sonic for each ops the offset, pitch and roll, 
given as elements of b. 
 
The entire calculation set was repeated in one session on Mon 8 Nov 
and the values are reported below: 
 
NB. On 15 Dec 1993 the atiS.50.10m data was reexamined. 
    atiS.50.10m 167:174 has been split into 167:170 and 172:174 because of  
    a radical change which occured on jday 171 at ????? 
 
ops1 
sonic.name   jdays   sonic.azm  prop.corr u.off  v.off  u.gain v.gain  
--------------------------------------------------------------------- 
atiK.50.10m  154:157  296.6      65.75     0.06  -0.03   1.03   1.03 
uw.100.10m   154:157  292.4      65.65     0.11  -0.01   0.96   0.96 
uw.175.10m   154:157  294.6      65.75     0.11   0.02   0.95   0.97 
atiK.250.10m 154:157  299.0      65.75     0.09   0.08   0.98   1.04 
 
sonic.name   jdays    offset pitch roll               b 
--------------------------------------------------------------------- 
atiK.50.10m  154:157   0.0   -2.0   2.9    -0.004  -0.034  -0.052 
uw.100.10m   154:157   1.0   -1.8  -0.7     0.010  -0.032   0.013 
uw.175.10m   154:157   1.0   -1.7  -0.7     0.011  -0.029   0.011 
atiK.250.10m 154:157  -2.0   -0.7   0.5    -0.015  -0.011  -0.008  
 
 
ops2 
sonic.name   jdays   sonic.azm  prop.corr u.off  v.off  u.gain v.gain  
--------------------------------------------------------------------- 
atiK.50.10m  157:163  296.0         0.0    0.06  -0.02   1.04   1.04 
atiS.50.10m  167:170  296.4         0.0   -0.02  -0.08   0.96   1.03 NEW DATA 
atiS.50.10m  172:174  296.4         0.0   -0.01  -0.12   0.95   1.01 NEW DATA 
uw.100.10m   157:174  291.2         0.0    0.10  -0.04   0.96   0.93 
uw.175.10m   157:174  293.9         0.0    0.11   0.01   0.95   0.95 
atiK.250.10m 157:174  297.0         0.0    0.12   0.15   0.99   1.02 
 
sonic.name   jdays    offset pitch roll               b 
--------------------------------------------------------------------- 
atiK.50.10m  157:163   1.0   -2.3   2.5      0.011  -0.040  -0.044 
atiS.50.10m  167:170  -2.0    0.2   1.1     -0.019   0.003  -0.019 NEW DATA 
atiS.50.10m  172:174   304   -2.3   2.7      3.040  -0.040  -0.048 NEW DATA 
 For the above I used wmax=5.0 rather than wmax=1.0 as elsewhere.  
uw.100.10m   157:174   1.0   -2.1  -0.6      0.008  -0.037   0.011 
uw.175.10m   157:174   0.0   -1.6  -0.6      0.002  -0.028   0.010 
atiK.250.10m 157:174  -3.0   -0.4   0.7     -0.032  -0.006  -0.013 
 
 
ops3 
sonic.name   jdays   sonic.azm  prop.corr u.off  v.off  u.gain v.gain  
--------------------------------------------------------------------- 
atiK.50.5m  174:181  295.6          0.0   -0.01  -0.04   1.04   1.03 
uw.100.5m   174:181  291.0          0.0    0.04   0.02   0.94   0.93 
uw.175.5m   174:181  295.2          0.0    0.09  -0.01   0.95   0.95 
atiK.250.5m 174:181  297.5          0.0    0.11   0.00   0.98   1.00 
 
sonic.name   jdays    offset pitch roll               b 
--------------------------------------------------------------------- 
atiK.50.5m  174:181   -2.0   -0.9   1.8     -0.020  -0.017  -0.032 
uw.100.5m   174:181    0.0   -1.9  -0.1     -0.003  -0.034   0.002 
uw.175.5m   174:181   -2.0   -1.5  -0.8     -0.017  -0.026   0.014 
atiK.250.5m 174:181   -3.0   -1.0   0.8     -0.027  -0.018  -0.013 
 
Checked these numbers against the two sets of plots 9 Nov 
 

Sonic azimuth errors  
 
The difference between the wind direction measured by the prop vane 
on a tower at 50m and the  
The total error = (u.err^2 + v.err^2)^1/2  
 
 
ops1    atiK.50.10m    uw.100.10m    uw.175.10m   atiK.250.10m 
	   0.170        0.301         0.413          0.679 
            
 
 
ops2    atiK.50.10m    uw.100.10m    uw.175.10m   atiK.250.10m 
           0.161        0.296         0.377          0.516 
 
 
        atiS.50.10m     
           0.163 
 
 
ops3    atiK.50.5m      uw.100.5m     uw.175.5m    atiK.250.5m 
           0.178         0.303         0.393          0.519 
 
Increases with separation distance 
 
--------------------------------------------------------------------------- 
 
The difference between the theodolite value for the sonic (Nominal) and 
the value obtained from minimising the error relative to the prop (True) 
                     (True - Nominal)degrees 
 
ops1    atiK.50.10m    uw.100.10m    uw.175.10m   atiK.250.10m 
           1.2         -2.1           1.7            2,8 
 
ops2    atiK.50.10m    uw.100.10m    uw.175.10m   atiK.250.10m 
           0.6         -3.3           1.0            0.8 
 
        atiS.50.10m     
           1.0 
 
ops3    atiK.50.5m      uw.100.5m     uw.175.5m    atiK.250.5m 
           1.4          -2.5           2.3            1.7 
 
  
 No perceptable tendency 
 --------------------------------------------------------------------------