SHEBA: Site 3 Messages, 52 Entries..

Station 3 was setup today, Sunday 12-Oct-97.

It is approximately 2 miles east of the ship on smooth first year ice
that is surrounded by older, hummocky ice.  There is about 2cm of snow
cover.
The weather held off nicely with low wind, partial sun and thin high
stratus cover.  Temps did drop into the -20 range.

TEG / Propane Status
	2 full bottles.

RF / LOS / Remote Console Problem
	Station Data is getting into the packet files, but the first
	attempt at remote console didn't work.  More careful typing
	might allow this operation.
	The ship's stack or perhaps the rear mast, appears to be
	slightly blocking the view of this station even though it is
	clearly in sight from the bridge area.

Caution: Logger connection
	The logger wasn't coming in at first.  The RJ45 connector on
	the electronics box power/connector panel was a bit loose.
	This could possibly happen again during a station move.


Gill Sonic:  NCAR asymmetric R2A sonic s/n 119 (?i think) was installed.

Compass/Gill Orientation:
	The physical alignment of the gill and the electronic compass both
	are pointing in the same direction: toward the mast as viewed from
	the hygrothermometer.   At the present time, this is looking pretty
	close to due west.
	Compass reading = 226.38
	Adjusted for Dec= 264.28  (ie declination = 38 which is
					consistent)
	Hand compass (with 38 decl) alignment of TRH xarm = 265


Station Orientation:
	The 4-component system is directly south of the station at the
	present time.  The sled is pointing away from the station and about
	10-m to the WSW.  The sun shadows will be longer from there but
	the scientific need is to obtain the maximum readings which will
	be more likely from due south.

Rad. Level: x=1.2, y=2.8
	NOTE: The electronic level was considerable off for this
	station.  A buble level confirmed visual inspection.  The
	readings shown represent the values after leveling with the
	bubble.

Hardware:
	The sawhorse was extremely difficult to setup because the legs
	were totally frozen in the tubing.  It took considerable
	effort to pound, screw, etc. them out.

	NOTE: it appears the bending of the sawhorse arrangement and
	the flex in the configuration may wobble the legs and cause
	movement, perhaps in high winds.

Station 3 was setup with the sonic aligned parallel to the electronic compass
north, with the north position facing 'down the TRH xarm toward the tripod' and
90 CCW viewed from the top from the sonic xarm.

This configuration will cause excess wind obstruction from the sonic's mounting
arm and needs to be changed so that the north faces in the parallel direction
with the sonic xarm.

Station 3 visited today:
Symmetric Gill sonic realigned to have 'north' pointing outward from the
boom arm per the standard installation technique.

3/31/99
This appears to have occurred at 19:00 GMT, Oct 15 - TWH

Station 3 visited

Gill sonic realigned to point north.  (also logged elsewhere)
Sonic height remeasured.  (also logged elsewhere)	
Removed Sled TEG vent insulation
Downloaded local data

Communications Note:
	Somewhat poor response on remote console operation for this
	station.  Didn't see anything obvious, the connectors seemed
	tight.  I did lower the sled's tow-bar which was between the
	sled and the ship, even though at most it would have obstructed.
	the lower 1/3 of the antenna (ground plane?)

	This evening, the console operations seem to be better....Maybe
	that was it.

Comments:
	Ice on domes for PSP-in/out, PYG-in
	Ice on inlet for TRH

  A first time trip to Baltimore, station 3. More
trail markers were added. A new configuration was
loaded at the site. Refer to message 57 for more information
on the new configuration.

  Because of the crak n the airport runway a new site
has been selected for the airport. It will be near
Baltimore whic may mean we have to move the station. I
do not see a decision being made until the runway is in.

  The TEG at Baltimore went down yesterday. At this time it is
unknown why it shut down. The battery voltage is dropping, approximately
1 volt in 48 hours. According to logbook entry 33, the station had
a full set of propane bottles on the 12th. We may be looking at a
maximum run of 12 days on propane. Station 2, Cleveland, should be monitored
closely since it is approaching this time window.

  The propane was changed about an hour ago. The TEG kicked
on after about 2 minutes. It took awhile for the system to
get fully operating. At one time there was a yellow flame
down in the exhaust. If the bottles were full on installation
then the typical operating period is about 12 days max.

  Ed went with us and decided that the site was still good
even with the new airport out there.

  The TRH was down at station 3 because we were not able to
reprogram it. The Rocky screen was useless. With the TEG running
the box should be warm enough by tomorrow for the Rocky.

UPDATE: Gordon was able to send fast commands over the freewave
link to Baltimore, station 3. This allowed us to reprogram the
TRH. It is now running.

  Jeff and I went to station 3 to get the RAM disk. We also spent
a fair amount of time coming back putting in stakes to flag the
road to the site.

  Gordon and I went to Baltimore to replace the TRH and
play with the TEG. Since the pressure setting on the TEG
to spec we did not try to re-adjust it. We did turn off the
automatic sparker by moving the palte which holds the switch
in.

  It appears that the auotmatic sparker had something
to do with the spiking we were getting on the TEG/Battery
voltage/current plots. It maybe the sparker was inducing
noise on the dc signals that were sampled.

12/18 ~01:00gmt
	Brushed frost off PAM antenna mounted on ship.  Twisted 4 rods at 
	base of antenna so they were symmetrical again, not skewed.

	Tested RF communication quality to Baltimore.  Still lousy.  Has 
	always been bad, but seems to have gotten worse in last few days.

email excerpt concerning 12/10 Baltimore visit:
---------------------------------------------------------------------------
	Yesterday's Baltimore trip was quite tame compared to the previous
trip last month.  We followed the normal staked route.  We came to one 15'
lead that had formed and frozen since the scouting party had found
Baltimore several days earlier.  After testing its thickness, we crossed
it without a problem.
	The big lead which had blocked our route for so long was also frozen 
over.
	My hat's off to Herman Nelson.  A Herman Nelson is a gasoline
powered heater that puts out massive volumes of hot air.  With its 10"
hose inserted into the propane tank door, it heated up the TEG and all
the electronics in no time, as well as defrosting goggles and warming
hands.  (The downside is that it weighs 500# and has to be muscled onto a
sled.)
	No marshmallows or smores this time as the TEG started right up.
(I had replaced the nozzle.)
	The TEG voltage rose slowly as the TEG heated up.  Eventually the
battery indicator LED's in the battery box went from flashing red to
yellow to green.  Then I turned on the instruments.  But that was too much
current draw too soon and the battery voltage soon dropped into the
flashing red.  So I waited a while, disconnected the 4-component fan and
the TRH fan, and then turned the key switch back on.  This time the
voltages held.
	I hooked up Rocky, ready to do battle with the CSI, but found it
was working just fine now.
	We then helped the CRREL tech with his drilling and core sampling,
I connected the fans back up and we were off, getting back to the ship at
4:30pm.
	Please send a jacuzzi and a masseuse.  The snow surface after the
past few storms is riddled with sastrugi- hard windcarved ridges up to
about a foot high.  Imagine riding for 5 miles across a series of
speedbumps every 10' in a car with no shock absorbers, towing a trailer. 

	And then when looking at the data from the ship, the voltages were
dropping...  (They have since leveled off, but at about 11.8V.)

	This morning I noticed an increase in Baltimore's RH at about 5am
local (about 13 hours after our return).

	With marginal voltages and the CRREL tech needing to return to the
Baltimore area, we decided to make a quick trip out today after lunch.  So
three of us headed out.  I was toolin' along in the lead (no pun intended) 
snowmobile about a mile from the ship when I saw ahead what looked like a
frozen over lead.  But I didn't recall a frozen lead that wide the day
before.  I stopped the snowmobile, then gawked at the 200' lead that
hadn't been there the day before.  I tested the ice with an ice chisel,
and the chisel went right through with little hesitation.  There was just
a skim of ice on the water, with enough frost on top that it looked much
the same as the surrounding snow, only flatter.
	We looked in the direction of the moon and could see no end of the
lead that way.  We traveled along the lead in the other direction, but
gave it up as a lost cause before long.  This was not a 10' lead where you
could expect two jagged corners to be touching where the ice sheets had
shifted.

12/24 ~20:30gmt
	Visited Baltimore.  Changed propane and flashcard.
	TRH fan was running and there was no unusual frost inside the intake 
tube or around the fan.  But to be on the safe side, changed TRH with one 
removed from Cleveland.  Used laptop to check temps and humidity.  They 
seemed reasonable.
	Slightly tightened N type coax connector on base of antenna.  
(Transmission seemed no better after returning to ship.)
	Pyg.out was clear of frost.  Cleaned moderate frost off other three 
domes.
	Brushed 3/4" of frost off sonic assembly with feather duster.  
Warmed heads with fingers (using ladder), but no significant frost remained 
after the brushing.
	Removed beacon as it wasn't working.  Computer showed it to be on, 
and a voltmeter showed 5V going into it.  Will take a new beacon out on next 
trip.

	Route to Baltimore has changed since last successful trip out there.  
About a mile from the ship, after crossing a 200' frozen lead , we were 
surprised to find stakes immediately after the crossing.  They angled off to 
the left (north) which seemed unusual, but we followed them anyway for a 
ways before realizing for sure that this was the distal portion of the `
Atlanta trail!  The two ice floes had shifted just the right amount to line 
up the near portion of the Baltimore trail with the far portion of the 
Atlanta trail.
	We backtracked, followed the lead in the other direction for about 
a half a mile, found the next section of the Baltimore trail and continued.  
The rest of the route was unchanged from the previous visit.  (So it included 
crossing the frozen 200 yard lead farther on towards Baltimore.)

1/1 ~21:00gmt
	Visited Baltimore.  Changed propane.  One tank was nearly empty, the 
other completely full.
	Rebooted EVE.  Copied files from ramdisk to flashdisk.  Changed 
flashdisks.
	Cleaned frost from radiometer domes.
	Cleaned heavy frost from sonic anemometer.  Used fingers to melt 
frost residual after brushing off bulk of frost.
	Replaced modem and antenna with spares.  Janet tested RF communication 
from ship, but it didn't improve.
	Tested to see that data was being stored on flashdisk.

	Found that Baltimore CSI data has not been recorded since 1/1 site 
visit.  During site visit Eve "POWR" command showed realistic values, but it 
turns out these are not current values, but the last recorded values.
	Had spare RJ45 cable with me at Baltimore, but vinyl cables in Eve 
box were too cold and brittle by that time to risk moving them.  POWR command 
output made it appear that data was being recorded correctly.
	On next Baltimore site visit will replace RJ45 cable and check 
communications using "talk" function.

1/6 00:30gmt
	Swung ship PAM base antenna and its bracket from starboard side to 
port side on its bracket.  Rear mast is now less in line with antenna and 
Baltimore.  Baltimore communications still not as good as other sites, but 
much improved.  If need be, could probably install longer bracket.

1/13 ~20:00gmt
	Visited Baltimore.  Changed propane and flashcard.
	Replaced CR10 RJ45 cable inside EVE box.
	Replaced sonic with a heated head sonic.
	Replaced TRH with one modified for sonic head heaters.
	Loaded new configuration program- format 52.
	Reinstalled previously removed and repaired beacon.

	Ann removed moderate frost from radiometer domes.
	The removed sonic was heavily frosted on all surfaces.
	Inlet of removed TRH was completely covered with frost.

	To get to Baltimore, we followed a new, nearly straight path from the 
ship that had been marked out by support personnel.

1/21 17:54
	Changed heaton to 600.  (10 minutes)
	Changed heatoff to 6600.  (110 minutes)

1/22 18:55gmt
	Turned Baltimore's sonic heaters off (heaton=0) due to drop in battery 
voltage.

BAL refueled.  Teg restarted with Rocket after trying Otten method.
The teg died several times but was restarted immediately.  Nozzle changed,
old nozzle quite blocked.  Battery changed.  Flashcard changed.  No box
fan present.  Cleaned sonic heads, fans and radiometer domes.  4-comp
fan is a four port with only the pyran.s attached.  Dug out teg box.  Eve,
fans and logger started.  Flashcard not being written to.

The BAL site is surrounded by fairly level, hard, windblown snow.  A ridge 
has formed running NW-SE, to the N of the site.  The ridge at its closest,
200 ft from the site and 2-3 ft high.  The areas to the N and E
of the site have many small ridges and leads.  The areas S and W are apparently
undisturbed.

2/4 ~20:30gmt
	Visited Baltimore.  Changed propane and flashcard.
	Changed TEG nozzle.  Voltages were still good, but nozzle face was 
quite dirty.
	Exchanged bad compass/beacon cable adapter with a good one.  Beacon 
now works.
	Removed and brought the 4-comp level sensor back to the ship for 
diagnosis.
	Removed light frost from sonic supports.  No frost on heads.
	Removed light frost plug from TRH intake.
	Upwelling pyg dome was clean.  Downwelling pyg dome had light frost on 
it.  PSP domes were more heavily frosted.  Thanks to warmer outdoor temps, was 
able to melt all dome frost off with palm heat.
	Removed pyg sun shields.  No snow inside, but some hard frost.  Frost 
mostly occluded the annular opening between the sun shield and the pyg case.  
Removed this frost.
	Did not bother cleaning frost from inside of psp ventilation housings 
because 4-port fan only has corregated tubes to pygs.  One tube doubled over 
blocks the other two ports.  (Atlanta is the same way.  The 
small ventilation proved not to keep the psp domes clear of frost anyway, so 
all available ventilation was put toward the pygs in November, when 
the sun was not up anyway.  The ventilation tubes are not quite long enough 
so that if all 4 are attached to the housing nipples, they're subject to 
falling off.  This is partly due to the fiberglass wrap around the corrugated 
tubes getting in the way.)

	Removed louver cover plate.  Pulled 4x2 PVC adapter out from 4" PVC 
elbow leading into sled box.  Thoroughly dug out sled box and cleaned frost 
from bottom vent holes.

	Checked to see that Flashcard was being written to after changing it.

	Sunday's scouting trip to Baltimore was turned back by a lead when they 
were most of the way there.  Monday's trip was turned back within a mile by a 
new lead.  Tuesday's trip was successful in finding a circuitous route, thanks 
in part to help from the captain.  The captain could see Baltimore through 
binoculars from the ship's bridge and so directed the scout team to Baltimore 
when they were near, but could not see it due to numerous pressure ridges.
Today, Wednesday, we made the successful service trip.
	The route to Baltimore crosses dozens of fairly recent leads and 
pressure ridges.  I can't tell which are a week old and which are a month old, 
but very few of them existed in the fall.
	There's a major ridge a few hundred yards N of Baltimore.  It varies 
in height from a few feet to 15-20'.

3/17 19:39 gmt
	Changed level coefficients using *4 mode of CR10 for Baltimore.  
Installed coefficients for level sensor s/n 0383.

3/18 ~20:00 UTC (11:00 AKST)
	Visited Baltimore.  Changed propane and flashcard.
	Changed TEG nozzle.  Voltages were still good,  
	Nozzle left out there in bottom of TEG box by accident
	Cleans holes out in bottom of TEG, only one completely
	blocked (hear TEG and side vent

	4-comp level sensor back on boom, not checked against a bubble
	level

	No frost on sonic heads

	Removed light frost from TRH intake Intake is loose. Take allen
	set on next visit.

	Pyg domes were clean.
	PSP domes moderate to  heavily frosted. Used alcohol and rag to 
	clean domes
	Fans running, but not blowing much

	No frost on sonics to clean

	Did not bother cleaning frost from inside of psp ventilation housings 
because 4-port fan only has corregated tubes to pygs.  One tube doubled over 
blocks the other two ports.  (Atlanta is the same way.  The 
small ventilation proved not to keep the psp domes clear of frost anyway, so 
all available ventilation was put toward the pygs in November, when 
the sun was not up anyway.  The ventilation tubes are not quite long enough 
so that if all 4 are attached to the housing nipples, they're subject to 
falling off.  This is partly due to the fiberglass wrap around the corrugated 
tubes getting in the way.)

	Called Jeff to see that Flashcard was being written to after changing i
	Level also working and voltages/load okay
.
	The route to Baltimore was fairly smooth. S and blowing snow since
	last visit has smoothed things out. No signs of open water or recent
	leads

3/31 ~01:00 UTC (04:00 AKST)
	Visited Baltimore.  Changed propane and flashcard.
	Changed TEG nozzle.  Voltages were still good,  
	Nozzle fairly dirty
	Cleaned holes out in bottom of TEG, This drained water out

	No frost on sonic heads

	Repaired bear damage New T/RH

	Brought in radiometers for John

	No frost on sonics to clean


	Data being written to flash card
.
	The route to Baltimore was bad in the early part. Crossed many leads
	Had to find different route even from Jay's this morning

Visit / Rad Systems at Clev. and Florida

Morning of 4/4/98, both systems had rime on both sets of domes although
the SW had considerably more (dime size on LW, 50% of dome on SW).
Cleveland was operating without any ventillators and it did have more rime
than the 'juice-can' aspirated Florida 4-comp but only slightly more.
Note the Cleveland system had the new 4-comp ventillator installed but
not turned on.  There could be an effect of natural ventillation through
the straight-in fan ducts.

By afternoon the LW domes on both Cleveland and Florida had cleared off
(sunny day, warm with the wind at ~10-20knots) and most of the rime on
all structures had gone as well.  The SW were still rimed though with
perhaps 30% more coverage on the unaspirated system.

19:00 AKST 4/4 (4:00 4/5 UTC)
	Domes cleaned.

Sa. 4/4, ~19:15 AKST, or 4/5, 4:15 UTC
Both SW domes were removed from the Kipp and Zonnens to begin the
dome vs no-dome intercomparison test with Florida.

The new 4-component individual fan technique similar to the 'juice-can'
system was powered up.

4/14 ~14:45 - 18:15 AKDT

	Service Visit to Balt.

	Site Condition:	~2.5 deep snow all around.
		Rough ice.  Dug out sled completely.
		Will have problems with water here
		later on no doubt.

	Swap TEG: New one was from Atlanta which had been cleaned				today.
	Refuel Propane
		1 bottle was full, the other was empty.
		Appears that the check-valve on one wasn't
		released.
	Swapped Battery: replacement=10.8, new=13.1

	Replace Gill #123 with ATI #302
		Angle of Gill with respect to boom = OK., arrow pointing
			correctly outward from boom.
		Height ATI = ~8' above the snow.
		Boom angle = 34 deg. magnetic (uncorrected)
	Added passive vent
	2 PV installed
	Swap Flash card
		Copied new config from flash.  Had trouble doing
		that.  Appeared that the file was corrupted.  Had
		to reload using xmodem.  Seemed OK. 
	4-comp Reinstalled.
		New ventillation system.
		Leveled.
		Height ~5.5'

NOTE: Station reported for about 30 minutes then died after we left.
	Console operation seemed OK, all sensor reporting reasonable
	values and power system also.

NOTE2:	4/15am local..
	Naturally after seeing the station go back down, cursing, etc.
	and about the time wrapping up base for night, station came back
	up and has been reporting for last 7 hours....wierd.
	Surmise maybe it just took awhile for things to warm up, maybe
	esp. the VME Backplane because of the bad initial copy of the
	stored cfg from flash and subsequent effort to download direct
	from Rocky. That might be consistent w/periodic outages of this
	stations' flash data over last 4-5 months. Also note that initial
	reporting showed Tbox at -15 deg which is consistent w/EVE box
	resurrection of unit undergoing test in chamber last fall (this
	box?)   Anyway, that's probably it.
	Will monitor and hopefully build up new VME/chasis and swap after
	few days on next visit.

4/22 ~0Z - 4Z Visited Baltimore

	Added:
		Ablation shield under sled (remaining in same position)
		Ablation shield under pentapod (ditto)
		Reburied everything and covered holes, etc.
		This also reduced a little bit the size of the drift
		around the sled

		Wind Generator
		SWin heater: 30-ohm single element
		SWout heater: 40-ohm double element

	Changed:
		Electronics box (hoping this will improve the cold-temp
				problems w/card,boot, etc.  New box
				has Schroff backplane, new button battery
				for CPU)
		1 Propane bottle
				It appeared that the one we swapped out
				after 7 days had quite a bit less than the
				other.
				NOTE: this is the same one that had been OK
				last week when we had a flame-out after
				only 1-bottle had been used....may still
				have something going on with the lines?
				keep track....

4/22 ~0Z - 4Z Visited Baltimore

New Orientations/heights:

        sonic arm: 36 deg mag, 97 inches
        T/RH arm: 126 deg mag
        radiometer arm: 205 deg mag, 61 inches

Other observations:

        When arrived, SWin frosted/rimed, SWout lightly frosted, LWin,out OK
        Sled oriented about same as before wrt tripod (about 290-300 deg).
        SW domes need new dessicant- we had none along so needs to be done
           next time.
        Installed 4 braided ropes on sled for use in possible helicopter airlift
           during the summer 

4/25 ~20:25gmt
	Attempted download of configuration 54 via RF to Baltimore.
	No packets appeared to arrive intact.  Got message: 
		...
		Retry 0: NAK on sector
		Retry 0: Retry Count Exceeded
		Please read the manual page BUGS chapter!
	Will wait for next site visit to upgrade configuration.

Visited Baltimore ~2200 - 2300 1 May GMT

Problem: Baltimore not working.
No evidence of polar bear damage.
Jeff took off and reattached battery cable,
Baltimore started working.
Apparently this was the problem, but we're not sure.
Jeff also replaced electronics box with one from Florida and put
previous Baltimore box in Florida.

We also replaced both propane tanks and flashcard.

There was a very small patch of frost on top of upward looking
SW radiometer that was cleaned. Doubtful data was affected.
Fans workings, no frost in T/RH intakes.

Performed calibration check with "wand":.
Time: 2225 1 May GMT
T (wand) =   -18.4                             RH (wand) = 69.2  %
Tdry (PAM) = -18.16 C  Tdry2 (PAM) = - 18.10   RH (PAM) =  73.51 %

2100 - 2200 2 May GMT
Peter and Jeff visited Baltimore

Installed wind generator grounding wire.
Put in ocean ice approx 30 m SW of PAM sled.  Marked with stakes.

Modified EVE box for ATI sonics.

Replaced dessicant in downward looking SW radiometer.

Adjusted voltage output on wind generator by turning pot 
1/4 turn clockwise.  Could not check due to light winds.

No frost or other problems seen.
 

5/12 ~21:30
	Got helo ride to Baltimore to fix it.  It stopped transmitting data a 
couple of days ago.
	No LED's were lit on the EVE computer.  No voltage was getting to the 
EVE box.  Found and replaced bad 15A fuse in battery box.  The fuse did not 
look black and blown.  Could it have had an intermittent connection in it, and 
have caused the two earlier blackouts?
	No frost on any instruments.  Actually, there was an icicle on the 
lower part of one of the black, radiometer boom legs.

	View from on high was incredible.  There are good sized leads all 
around the region.  There's a continuous strip of ice connecting Baltimore to 
the ship, but there are N-S leads on either side of the strip.  One lead goes 
from just barely west of the runway off the port side of the ship, to about 
300m west of the Baltimore site.  Near the Baltimore site, this lead is about 
30m wide.
	The ice pack south of Baltimore is riddled with leads, starting 
perhaps 700m south of Baltimore.
	Many of the visible leads had open water over more than 50% of their 
surfaces.  Some had ice growing towards the middle from both sides.
	The helicopter pilot said there were many more leads, and much more 
open water than there was one day earlier.

	The sky seemed full of lead smoke and water sky bands over the various 
leads.

	There was about 5" of new snow in the Baltimore area, that I sunk into 
with each step.

As Ed wrote earlier the TRH is acting up.  The new TRH is in the lab and I will replace on the next visit to Baltimore.

Dave

Installed the spair TRH and changed the propane tanks.  The compass reading on 
the sonic boom was 68 degrees TRUE and the digital compass was reading 336.09 
(w/decl). This should be 90 but it's ~91.91 degrees.  Is this within your 
tolerances?  The instruments looked in good shape and the flash card was swappedout, then I checked eve with Rocky.   No leads insight of the site.  We remarkedthe "new" trail with the "old" markers from what was left of the old trail. 

Your amigo,
David M. Costa 

note: I did NOT replace the TEG nozzle.

Finally made it to Bal.  The instruments looked good and the LEDs in eve and
the batt box looked good.  I plugged Rocky in and couldn't get a prompt. I had
to cycle power on eve. That worked and I checked out the flash card and all the 
data was there. Changed the flash and propane.   Systems looked good.  I felt
the Freewave to see if it was running, it was cool. I check the voltage 13.67 v
it seemed to fluxuate with the WG. I also noticed the RF out cable was VERY 
loose.  After tring to tighten it for a while I noticed it had left handed
threads.  What's up with that??? Now it's good and tight. While I was putting
it back in place I noticed the LEDs in front. 
carrier detect	ON 
clear to send	flashing
transfer	OFF

I watched the open TEG voltage while changing propane. It held steady at 14.50v
Installed ablation cloth around the sled and under the tripod.

Back at the ship we had data coming in, but I had to reboot pampoll first.  

I tried to check again at 2200 and we stopped getting data ( all stations ) 
at 1900.

dmc

Went to Bal by helo yesterday ( 6/18/98 ) for a check up.
The bottom of the box was in the water ( slighty salty )  about 1.5"  There was
some ice on the SW radiometers that got cleaned.  

heights
263 cm	middle of the sonic boom to surface
171 cm	end of TRH shield to surface
171 cm	from middle of radiometer to surface

compass 70 degrees    Rocky 342.06  ( w/decl )

The TEG nozzle had a tiny bit of 'tar' on it and I switched it with a new one.
The flash card had the correct days on it ( 155 - 169 ).  I switched out the 
propane and raised the sled about 4".  We might punch a hole in the ice later
to see if some water will drain down, not up.

I. M. Fly Boy

We went to Bal by helo and changed the propane and flash card.  The instruments
were a little wet. 1030 AKDT June 29, 1998

heights
268 cm	middle of the sonic boom to surface
180 cm	end of TRH shield to surface
179 cm	from middle of radiometer to surface

compass 72.5 degrees    Rocky 340.95  ( w/decl )

The flash card had the correct days on it ( 169 - 180 ).

We leveled the radiometers with the bubble level and Rocky read:
x = 0.23	y = -0.10

Team SHEBA

Visited Baltimore at 1735-1830 UTC 980709
General site description:  ABout 3 cm of crusty, coarse-grained snow(loose ice?)around tripod.  Most of floe has no snow or just this coarse-grained snow/ice.  Don Perovich reports that the meltponds have gone down 5-10 cm in the past 10 days, probably because the floe has become lighter.  ABout 6-10 cm of wet, slushy snow near sled, but sled in a self-made meltpond.  The plywood has some water on it, but the sled, including the skis, are totally free of the water as the skis are sitting on some 2x4s on top of the plywood.  One side of the plywood is 
near the center of the meltpond, and needs to propped up with some wood on the 
next trip.  The ice thickness in the meltpond drainhole is 114 cm, with a 3 cm 
false bottom in it.  Hence, the sled is in no danger of melting through in the 
near future.

Radiometers:  All OK.  Leveled the radiometers with the bubble level.

Tsoil, Gsoil: The Tsoil sensor was in a meltwater crack about 8 cm deep, with the crack oriented towards the SW.  It's likely that it was receiving significant amounts of at least reflected solar radiation, if not direct.  Wrapped Tsoil 
sensor in Al foil and repositioned on top of the ice and covered with about 3 cmof coarse-grained snow (ice?) crystals.  
The flux plate was in a visible melt crack in the ice, but the plate was only 
visible by peering carefully in a certain direction, so it was probably not getting direct solar radiation, but maybe some reflected.  It was seen to be 
oriented at a 45 degree angle with the dot up, so we decided to dig it up and 
reposition it. It was wrapped in foil, positioned on top of the blue ice with 
the dot up, and covered with 8 cm of crusty, coarse-grained snow. 
 

Propane and flashcard replaced.  Eve and teg box lids cracked even more than 
before.

Made height and angle measurements:
Heights:
Sonic - snow: 269 cm
Downward looking radiometer domes to the snow: 179 cm

Angles: (the following angles are very tentative, because another compass was 
used than at other sites, and the readings with the ship orientation and the Eve output was significantly different than the reading from the handheld compass.)
Radiometer arm: 207 deg mag 
Compass arm:159 deg mag (note that Eve was reading 312 deg mag - 336 deg True.  Even if we assume a 180 deg error, there is still an error equal to the declination.  Confusing- problem with compass??)
Sonic arm:48 deg mag
tripod to ship: 338 deg mag (note that Splus showed a direction from Fla to Bal of 165 deg T, which should give a 321 deg mag reading to the ship from Bal - 
again, a significant error)  

Sonic-sled angle: forgot to measure, but about 320 deg T

Took numerous photos of tripod, sled, area, including 5 from the helicopter.

Site visit Baltimore -- July 20, 1998, 2130-2300 UTC

	Put supports under sled plywood base, which is in a meltpond.  Tripod 
leg bases are also in meltpond of their own making.  Raised the two legs on the sonic side by putting 4x4s under the plywood pads, raising them out of the 
water, and extending the legs. This leveled the sonic arm.  Radiometers were 
then leveled.

The Gsoil was oriented at a 45 degree angle and the Tsoil had worked its way 
into the ice about 6-7 cm.  Both were repositioned at the surface, covered with a thin layer of granular ice.  Gsoil had dot facing up.

Propane tanks and flashcard were swapped.

Drain hole in sled meltpond showed about 105 cm of ice under sled, so no 
immediate danger of melting through.

Site visit Baltimore -- July 30, 1998, 1730 - 1900 UTC

	High albedo at site today as a coating of light snow covers area, slush
ice on all of the melt ponds.  Tripod and TEG look good, TEG staying above the
melt pond that it is in.  Back legs of tripod staying above the melt ponds
that formed around them.

	Tsoil and Gsoil not visible, probably 4cm to 9cm deep, covered by small 
snow drift, induced by leg of radiometer stand.

Propane tanks, TEG nozzle, and flashcard were swapped.

Drain hole in sled meltpond showed about 90 cm of ice and melt pond surrounding
sled 40 cm deep; Sled sitting just above top of melt pond on 90 to 120 cm of 
ice so no immediate danger of melting through.

Heights:   Radiometers  176 cm
           Sonic        297 cm

Directions:
	    Compass arm    155d true  (compass dec 22.5d)
            Sonic arm       68d true
	    Radiometer arm 239d true

6/1/99 email from Ola Persson:
For Baltimore, my personal logbook states that the radiometers were leveled
on July 30 near 1800 UTC.  Sorry for neglecting to include this in the
electronic log.

Site visit Baltimore -- August 10, 1998, 2210-2330 UTC

Foggy, light/moderate wind.  Ice melting. The meltpond around the sled has 
melted through or is thin in a few spots.  But most of it has 40 cm of ice below
the water.  The ice pillar under the plywood has eroded from the sides but still
provides adequate support.  With the addition of the ice pillar, there is 75-80 cm of ice under the platform -- still OK, but needs to be watched, esp. the 
erosion of the pillar.  Moved sled to the plywood edge closest to the edge of 
the meltpond where ice appears most solid.

Changed propane and flashcards.

Leveled radiometers and wiped off water drops off of them (esp SWin).
Measurements: nearest meltponds to the radiometers are 11 and 13 meters away
              height of lower radiometer domes to ice: 183 cm

              sonic height: 117 inches
orientations: compass arm 141 deg T (22.5 deg decl)
              sonic arm 55 deg T
              radiometer arm 221 deg T
 

wand calibration @ 2250 UTC: Twand=0.3 deg C  RH=92.3%
                             T1=0.51 deg C   RH=102.7%
                             T2=0.23 deg C

Flux plate was in a water-filled crevice 9 cm into ice and was tipped about 30 
degrees. The plate was repositioned at the surface of the ice (dot up) and 
covered with a thin layer of ice granules.

Tsoil in crevice 6 cm into the ice and is not in water.  Repositioned @ top of
the ice & covered with ice granules.

Photos taken

Went to Balt by helo yesterday ( 8/24/98 ) for a check up.
The site is on 80 - 88 cm of ice. The ice guys were there, too.  The melt pond
at the sled was frozen enough for me to walk on and the sled seemed safe.  The
ponds in the area were frozen over but there was some open water in the bigger
ponds ( with some seals ). 

heights
293 cm	middle of the sonic boom to surface
237 cm	end of TRH shield to surface
200 cm	from middle of radiometer to surface

compass 181 degrees ( no decl. correction (magnetic) )   Rocky 278.26  ( RAW ),
Rocky said the decl. is 31.5 degrees. Is this some automatic reading updated by
the satellites or something that has been entered by hand?  
Rocky 309.76 (w/decl)  I might have read the wrong
end of the compass needle and it also could have been 001 degrees.  Can 
we check from the winds or should I take another trip out there?  Off by 
seven degrees???

RH was 101.43% seemed a bit unreal but couldn't see anything wrong.  The RH 
sensors on the tower are high too and we suspect a problem.  

The flash card had the correct days on it ( 222 - 236 ).

Costa

Changed the flash card, propane and TEG nozzle. The flash card had the correct
number of days ( 237 - 250 plus 236? ).  The nozzle looked clean.

The radiometers were bubble leveled.
Rocky read  x = 0.44, y = -0.07 

The sonics were thickly covered with rime, but apparently not blocking the 
sound waves.  Radiometers were clean.

We did a calibration with the NOAA TRH wand.
The wand read  temp = -1.35, RH = 93.3
Rocky read  Tdry = -1.22 Tdry2 = -1.41,  RH = 103.07

Compass 233 magnetic,  Rocky  242.42  (raw), 273.02 ( w/decl ),
decl = 29.6 west is neg

The site is ~ five miles from the ship and is unable to communicate with 
pampoll.  We couldn't see the ship from the site ( fog ) and it's ~ 104
degrees off the bow.  The status LEDs were solid red on 'carrier detect' and 
blinking red on 'clear to send'.  The matrix in the manual lists that as
1. Powered, disconnected
2. Master calling slave through repeater
3. Mode 6, disconnected  ( Point to Point Slave/Master Switchable )

I don't think we have a repeater, do we?  The LEDs were on ie. power on.  
Mode 6 seems OK to me.  The ship and station have been rotating quite a bit
and the signal was getting spoty so I think we lost 'line of site'.  I will
dink around with the ship antenna and try to pick link up. 

The station is located near the center of a flat floe that is about 200 meters
diameter. Surrounding the floe is a very active region with many pressure ridges
and open water regions (approx 15% open water).  There is fresh snow about 4 cm
deep with deeper drifts on the Baltimore floe.  Area immediately under the 
radiometers is flat and snowy with no evidence of melt pond visible on the
surface.
Peter took pictures.

PAMette

Stopped by Batl to check the flash card and RF transmitter.

The flash card was collecting data.
The RF transmitter has ~12.5 volts in.

The site is 5 miles away and the manual claims the link is good
up to 20 miles.  We can try moving the antenna on the ship?

The heaters on the sonics don't seem to be coming on when the counts
are bad.  We covered one of the heads and Rocky never reported the 
heaters ON.  I stripped the heaters off of the bad Atl. sonic head to
try at Balt during the next visit but, it would seem more like
a software problem.  Does EVE have some kind of check to know if
the heaters are 'really' ON? 

later

	Sat Sep 12 1998

Ed and Scott went searching for Baltimore and found it! 
Rocky could not be used so all we did was swap flash cards and shoot
some angles. We know Baltimore is alive because we get trickles of
data now and then. There are no LOS problems, just a clear path
to the ship.

One minor detail : The GPS data from Baltimore lists only the degrees.
The min. and sec. values displayed by show_misc are actually the 
degree value.  (We see that the other stations report this way to though.
A programming glitch?)

Our plan at this point is to allow Baltimore to run until it`s scheduled
propane refill, sometime around Sep 20. We will then helo it back to camp
and retire it from active SHEBA duty.

Baltimore`s compass is pointing at 293 degrees magnetic.  How do we update
this value in the data stream.

With the better weather today, we had a chance to get up in the helicopter
to look for Baltimore, which we had not heard from in 4 days.  After the storm
of the last 4 days, we were not sure even where the station might have drifted
or what shape it was in, considering Maui's fate.  But we found it fairly
easily almost where we left it, 10 km at bearing about 100 degrees.  As we
landed, the sun came out, the helicopter pilot turned of his engine, and
you couldn't have asked for a more serene setting.  Baltimore was saftely
perched in the middle of a solid, 70-m diamater floe with newly ridged ice east
and south and open water north and west.

The TEG was still running although the propane bottles had been switched 2
weeks ago today.  There was just a bit of clear ice on the down-looking
pyranometer, which I cleared.  The ATI sonic was also coated with 1/4 inch
of clear ice, but the transducer faces were clear.  Wow, those sonic heaters
are potent.  I knocked most of the ice off the sonics.  Scott swapped flash
cards and confirmed with Rocky that the station was still recording.

We removed the omnidirectional antenna and installed the Yaggi.  In lining it
up though, we may have identified the problem.  There`s a Mt. Shasta type
rubble pile in a direct line between the sled and the ship about 600 m away.
We can see the ship around that pile but not above it, but its not clear that
the PAM antenna can see the ship's antenna.  Does the line of site between
antennas need to be clear?  Jumper's suggestion was to chop down that rubble
pile with an ice chisel, the only tool of destruction we had with us.  That'd 
take about 4 hours.

Back on the ship, we were still getting no data by radio from Baltimore.

We're implementing John's plan of letting the station run out of propane to
see how long it will run on just the solar panels and the wind generator.
Whatever, we'll have to pull that station in by next weekend.

After Jumper saw Baltimore yesterday, he was concerned about its survival.
It was sitting on a 70-m diameter floe that was about 30 cm thick.  There
was open water on two sides and ridged ice on the other sides.  The area was
fairly active.  Jumper worried that if Baltimore`s floe cracked, there would no
place nearby to land a helicopter.  Since today was a decent flying day while
the forecast is for deteriorating weather tomorrow, we decided to fetch
Baltimore home today.  The key went off at the station at 17:20 GMT today,
September 21.

In retrieving the station, we lost very little equipment.  The in-ice
temperature sensor and the heat flux plate were frozen in the ice and 
irretrievable; we cut those cable.  We also had to cut out the middle section
of the ATI sonic cable.  For some reason, this had not been threaded through
the PVC pipe but had been wound around the outside and also had become frozen
in the ice.

Our decision was right.  As we worked, the northeast corner of the floe,
10 m from where the helicopter landed, was crunching inward under pressure.

during unpacking, the ati sonic v vector was discovered to be bent.
it is not known at this time how long it has been bent. v vector is
reporting 2 M/S in the lab, and v samples is low (15 instead of 20).
Three possibilities are: 
1.) it happened during a bear visit (last one at maui was about
    one month before teardown
2.) it happened during teardown
3.) it was man handled in Customs

Logbook	Date	Site	Comment highlight(s)
Entry	(local)

33	oct 12	3	Setup 2 mile E of ship (NCAR R2A sonic sn 119?)
40	oct 15	all	Sonic hts tabulated (345-348 cm to center of array)
39	oct 16	3	Reoriented Gill w/ `N' along boom
55	oct 20	3	New stn config
78	oct 25	3	No visit, TEG shut down
80	oct 25	3	Refueled, new config??
85	oct 26	3	Retrieved RAM disk
98	oct 29	3	Replaced TRH

120	nov 11	3	Routine maintenance, new fan and heater

140	dec 10	3	Refueled
170	dec 24	3	Swapped TRH with one removed from Cle

183	jan 1	3	Replaced modem and antenna; heavy riming
213	jan 13	3	Installed Fla sonic/TRH; replaced CR10 cable

264	feb 18	3	Routine maintenance 

296	mar 4	3	Routine maintenance
324	mar 18	3	Routine maintenance
344	mar 30	3	Repaired bear damage; replaced hygrothermometer

395	apr 14	3	Replaced Gill #123 w/ ATI #302; measured hts
			and azimuths; Installed TEG from Atl, 2 PV panels
415	apr 22	3	Installed wind generator, SW heaters;
			measured hts and azimuths

443	may 1	3	Replaced EVE
446	may 2	3	Changed EVE config for ATI sonic
462	may 12	3	Replaced fuse; aerial site description
466	may 14	3	Ed eye-balled sonic level??
485	may 25	3	Installed spare TRH; measured sonic azimuth 
491	may 29	3	Notes cleaning of radiometers
495	may 30	all	Tabulation of site characteristics in late May

506	jun 4	3	Tightened RF cable
541	jun 18	3	Measured heights
544	jun 21	3	Notes drilling hole in ice
561	jun 30	3	Measured heights, azimuth; leveled rads
562	jun 30	all	Comparison of bubble & electronic levels

574	jul 8	3	Repositioned "soil" sensors;
			measured heights and azimuths
591	jul 20	3	Repositioned Tsnow, Gsnow; leveled radiometers;
			raised tripod legs to level sonic arm
606	jul 30	3	Routine maintenance; measured hts and azimuths;
			leveled radiometers

613	aug 4	all	Tabulated offsets of electronic levels
626	aug 10	3	Leveled radiometers; measured hts and azimuths;
			repositioned Tsoil and Gsoil
650	aug 24	3	Measured hts and azimuths

672	sep 6	3	Routine maintenance; radiometers leveled
676	sep 8	3	Check flashcard, RF transmitter, sonic heaters
684	sep 12	3	Routine maintenance; measured compass bearing
700	sep 20	3	Cleaned radiometers, sonics; changed antenna
703	sep 21	3	Dismantled Bal in anticipation of ice trauma
713	sep 28	all	Summary of site characteristics

Note that `Routine' Maintenance is often more than refueling, swapping
flash card, and de-riming sensors. However, here I am focusing mainly on
sensor maintenance.