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Monday
17 November 1997 - AASTO completely stuffed
Greetings
from the Pole! It's not good news, I'm afraid. Mcba - could
you please ensure that this message gets to Jack - I'm not
sure of his address.
There
is *no* freon in the sight tube. The freon pressure guage
reads zero. There is massive corrosion of the area around
the exhaust stack (inside the AASTO). I don't know what corodes
stainless-steel braided hose, but this stuff has had a real
good go. Remember the aluminium can the Brownell valve came
in? Coroded right through. A lot of stuff is completely ok.
However, it seems that anything that was *cold* has condensed
out something extraordinarilly viscious onto it, which has
then proceeded to chomp it to death. The top of the TEG unit
is coroded, and covered in white powder and yellow stuff.
The aluminium tape on Ethan's experiment near the port hole
is coroded. (Did I mention that Ethan's experiment is fully
installed, complete with computer, electronics, blackbody
source and scanning head?).
Also
badly hit are the tools, screws etc that were on the bunk
near the window that Paul had propped open. Some of the tools
are beyond recovery. The perspex cover at the base of the
nism has been removed, and the inside of the nism support
box, bull gear etc are covered in white corosion which is
*gooey* - ie I can scrape it off with a screwdriver and frighten
Ant with it.
There
are white crystals of something in little pools on the bunk.
Parts of the rack are coroded, but mostly the electronics
looks ok. Only the things that were exposed to cold seem to
have been attacked.
Another
thing - all the paper in the AASTO is totally brittle - just
like the Dead Sea scrolls. If you pick up a sheet of A4 paper
(a circuit diagram, for example), it just breaks in half.
This
seems to fit a theory of the freon leaking into the burner,
being catalytically converted into HCl and HF, then when Paul
opened the place up and let some things get cold these acids
condensed onto them and chewed them out. If this theory is
correct, Ant and I would *urgently* like answers to the following:
1)
Is this stuff dangerous? (ie - aluminium fluoride, copper
fluoride (yes, the black body heatsink copped it), iron fluoride,
stainless steel fluoride, paper fluoride, etc.)
2)
How do we clean up the mess in a safe way?
3)
Are there other dangers we should know about?
Once
we're sure, we should inform Paul.
I'll
send this message in two parts. Ev Paschal is in for a bit
of a shock when he arrives! Things may actually not be too
bad once we clean the mess up, but we won't know till we have.
Cheers,
john
Part
2......
Well
guys, I thought that was enough bad news for one message,
so here's the rest. The whole program at Pole is about 2~3
weeks behind schedule now. Fred Mrozek arrived on the same
flight we did. None of the stuff we shipped has arrived. It
would be nice to think it was going to arrive real soon now
(along with Ev Paschal - we could reaaly use that guy right
now). However, as I type there are two Hercs parked outside
the dome with all 8 engines *off*.
The
Hercs flew in at mid-afternoon (we were on one), and they
set off full of hope and end-of-season winteroverers, but
then the weather at McMurdo closed in so they returned to
Pole. They sat for about 4 hours with the engines running,
then decided it was silly and turned them off. Rumour has
it they will try to restart them tomorrow, then fly out with
no passengers. I've also heard (from Pernic) that they've
just stuffed a C141 at McMurdo when the doors of the front
landing gear got ripped of in the snow and damaged the airframe.
The C141 is on its way back to the States. (Actually I always
thought those doors were in a silly place...)
Hey,
it's not all bad, there's good news too:
The
AASTO is in great shape (externally). There's a huge snow
drift behind it and a bow wave in front of it, but it's still
clear. There's almost no snow *on* it, or the nism, mism,
or Ethan's thing. (Actually, there's a nice snow drift behind
each of the instruments, but not troubling them. There's snow
packed around the freon heat exchanger. There's *no* ice on
any of the windows (nism/mism). The G-tower is free of snow,
as is the AFOS. Ant climbed the tower and said there's a few
individual particles on the AFOS window. The supervisor computer
is up and running.
The
L-shaped box is alive and well and sitting in the AASTO (Only
mcba knows what this means - I haven't been game to open it).
The only other bit of damage is that one side of the fibreglass
nism box has separated from the foam and peeled off - very
wierd.
Mcba
- I've asked for an IP number etc for the Mac, but knowing
how slow they can be here (and there are already 175 people
here, plus two Herc crews), I plan to use the one we used
for Andre's PC last year. Can you tell me the secret numbers
for gateway, domain, blood group, nationality etc.?
At
least two of the Sonnenscheins have split cases, but no electrolyte
appears to have leaked out - or maybe that's what's eaten
all the other stuff in the AASTO? Hmmm. Interesting theory.
If it leaked on the carpet and then Paul put the heater on
the carpet... I'll check that out tommorrow. All of the DCU
batteries are ok, imcluding the spares. Looks like Jack's
Powersonics cope with the cold better than our German batteries.
Reading
this again I see that it was supposed to contain mostly good
news. Well we're not in McMurdo anymore, the food's great,
Ethan left a Mac 5300 in the AASTO, we finally got a change
of clothes after 4 days in ChCh with our checked bags firmly
crated for the C141, the first Herc we tried to fly to Mactown
in actually *discovered* that there was a gaping hole in one
fuel tank before we ran out of fuel, we didn't catch fire
when we landed again at ChCh (much to the disgust of the 4
fire engines), New Zealand's crops should recover in a year
or two from the 20,000 gallons of JP8 we sprayed over them,
there's a great bunch of videos to watch while we wait for
our stuff to come (including a beaut one called "Head
Cleaning Tape")...
Cheers,
John
Part
3.....
Well,
things went a bit slowly today. Mainly we ran around getting
IP numbers, trying to find out why the phone doesn't work,
who stole our Aussie flag, wondering whether we really *did*
take the Phillips cro back to UNSW (can't find a trace of
it here, and it's supposed to be *dual* trace), and trying
to tink of excuses for not cleaning out the AASTO.
Eventually
we ran out of excuses, raided the Janitor store, and towed
a bunch of cleaning things across on a sled. We also borrowed
the R2D2 vacuum cleaner from MAPO and have started the ugly
task.
Meanwhile
we borrowed a 1500W thermostatted heater, so life is about
to get easier.
I
can talk to the Supervisor computer with the keyboard, but
can't get it to do anything interesting because I've forgotten
what to say to it. When I type "test" it admits
to having 14 Dallases a-dangling, but only condescends to
tell me the temperature of two.
I
can't telnet to the Supervisor from pharlap.
There
is now only one Herc parked forlornly on the forecourt. The
other left this afternoon after they spent four hours getting
it started. The process involved four Herman Nelsons, which
were used to heat the donks and the APU. Apparently once one
engine is running, they can circulate oil from it to the other
3 and warm them up too. I'm not sure if it arrived at McMurdo;
if the weather was bad it was going to divert to Siple Dome.
Actually,
we *did* find a clue to the Phillips cro disappearance - a
broken knob on the carpet. It seems there was a violent struggle,
probably injuries sustained by both parties, but so far no
further trace...
The
386 computer and monitor both have brown goo running out of
them. We put them in plastic garbage bags and sledded them
across to MAPO.
Ant
went off joyfully to talk to Cargo but came back a bit depressed.
Either it was the ugly-looking blokes masquerading as cargoids,
or the fact that the only boxes of our stuff that have arrived
are the ones we don't need yet.
My
driving lesson in the Sprite went a bit flat when the instructor
couldn't get it started. We'll try again tomorrow. The vans
and shuttles aren't running yet. So, with one Sprite un-startable
and the other one missing its key, we ended with no option
but to lug a sled across from the MAPO building. When we got
there we knew exactly how Scott felt - there was a bloody
Sprite sitting there with its engine idling!
Wind
is forecast to drop tomorrow. Does anyone remeber where they
put the G-tower crane at the end of last season? If not, we're
happy to hurl the T-mount off the top, but would prefer to
handle the AFOS more gently.
Andre's
Lindblad is still sitting happily near the G-tower, with very
little snow around it. No doubt it's cheerfully receiving
signals from the LEOs, bouncing them off the end of its transmission
line, and sending them back again.
Ant
reckons we need a whiteboard in the AASTO. Good idea, Ant.
Andre...?
Ok,
back to the cleaning. The spray-on clean everything detergent
(unsuitable for food preparation surfaces) should have thawed
out by now.
Cheers,
John
Part
4......
Thanks
Andre and Mcba for your emails. We're making progress, as
will be seen in a moment.
Today
began with the stranded Herc still sitting outside the dome.
Apparently they got it started, but had the usual problem
of the oil seals on the propellor pitch unit leaking, so they
turned if off again. They'd better move it soon or the local
yobbos will strip it. Already the radio aerial has been bent
and someone has souvenired the hubcaps...
As
I type a second Herc has arrived to rescue it. They've unloaded
a dirty great generator, plus a bunch of Herman Nelson heaters.
There's now a Herman Nelson hooked up to each propellor hub
with a big tube. They're keeping the engines running on the
second Herc; a clear sign of learning behaviour.
We've
located the box with the G-mount crane, and unpacked the box
of useless odd and ends.
Today
we finished cleaning. We soaked all the tools, then scrubbed
them with scouring pads, dried them and put light oil on them.
We now have a usable set of tools, although some look like
they've been salvaged from a marine wreck. I don't know what
it was that attacked all the steel work in the AASTO, but
we've taked some samples which I want to get back to UNSW
to be analysed. Then we should patent it.
We
also cleaned up the electronics rack, which has brown goo
on it that eats through your skin if you touch it. A bit more
vacuuming, and now the AASTO is like a civilised place again.
We got a 1500W thermostatted heater in, and after a bit of
experimenting and a lot of arguing found that if the knob
is vertical the temperature of the AASTO oscillates stably
between 16 and 21C.
We
now have accounts on both pharlap and magnolia. Please send
email here, as we're not necessarily up when the satellites
are.
Something
very bad has happened on the nism power supply board. It seems
to involve the over-voltage protected, short-circuit proof,
over-temperature protected, guaranteed indestructable Siemens
highside switch setting fire to itself. It's also had a go
at the cicuit board and a few other things around it.
This
next bit is mainly interesting to Michael Ashley: namely a
potted history of attempts to talk to the supervisor computer
follows. First we tried a ctrl-alt-s in order to check the
disk drive settings. No response. Then I remember that only
some keyboards can do that (sort of like how only some people
can smell garlic). I therefore swapped it for the one in the
L-shaped box. That didn't work at all. This suggested two
possibilities: 1. someone sent down a dead keyboard as a kind
of pratical joke, or 2. I hadn't plugged it in properly.
It
turned out to be the latter (as a result of trying not to
get eaten by the brown goo). Once that was fixed I checked
the settings: all were ok: Type 48, 1572, 16, none, 1572,
63, 773. Whatever I do, I get: "Fixed Disk Controller
Error".
So
I gave up on the hard disk.
Turning
to the floppy, the one in the slot is AASTO disk backup 2,
RS 10/1/97, which someone has written "old IP numbers"
on. So I downloaded the latest version of the software (aasto-97aaa6.exe)
using an old M*c*nt*sh we found lying around the AASTO, overwrote
the file on the floppy and rebooted aasto.
Then
followed pages of happy little starting messages from aasto
- all about how much fun it was being a computer, how much
it was looking forward to doing calculations for me, finishing
up with: "invalid directory" "This RTK version
contains debug code" (Hey-a Michael! How coma we don't
getta da version without de bug??) "SUPER version 3.0
etc. "Nov 16... hey, how come it knows the date? "can't
open file <cosole.ini> "Error 128 CAN'T_OPEN_FILE..
hey, now it's shouting at me! "Nov 16 08:04:10 SUPER>
Now
that's what I call a good start. It not only reads all 14
dallases, but says where they are. There'll all working, by
the way.
But
we still can't telnet to it!! When it's powered up the green
light on the ethernet hub next to that port comes on, so at
least the hub can see the ethernet card in the aasto. I even
tried a different cable, risking death by brown goo, but no
joy. Also, when the aasto is booting, one of its happy little
"I like being a computer" messages is: Found NE2000
V11 packet driver at INT 0x61 00 40 60 2B 00 FF TTCP kernel
successfully installed which I take to mean that it *thinks*
it can talk to the outside world.
In
the absence of any other ideas, should we dismantle the aasto
and put in a new ethernet card? If so, would a new hard disk
be in order? If so, which one? Most of the brown goo has gone
now, by the way.
End
of bit that's only interesting to mcba. Start of bit that
mcba won't be so interested in. We decided to fire up Ethan's
Mac, partly to see if it had survived a few months of temperatures
down to -79C (not to mention the attack of the brown slime).
I should mention that there was a Compaq 386 PC sitting next
to it (which I would have *much* preferred to use), but there
was a stream of slimy liquid coming out of the monitor, and
the PC itself had cleverly glued itself to the bench with
its own bodily secretions. We prised it off (with difficulty),
put both in plastic bags (the ones they line the dunny with),
and sledded it across to MAPO.
Anyway,
back to the Powerbook 5300. Works fine. Remembers all its
ethernet addresses. Just switch on, click and point. Oh rapture!
(my Mac is still in my bedroom, by the way, on account of
the brown slime).
That's
about enough for one message. Cheers, John
Part
5.....
Good
news at last! Network contact was restored to "super"
today at 3:30pm, via telnet from poodle.spole.gov. We'll leave
it up and running, so mcba you can have a go at contacting
it when next a friendly satellite is up.
Actually,
quite a lot has happened in the past 24 hours. Last night
about 10pm they finally got the stranded Herc running, and
it set of for McMurdo closely followed by the one that came
to rescue it. Unfortunately they chose to leave just as Ant
and I were walking back from the AASTO in a 20 knot wind,
so we had to stand and wait at the edge of the skiway for
yonks. Neither of them came back, so either they made it back
to McMurdo or they crashed and burned.
Today
a couple of CMU students showed up and spent the morning dismantling
their gear and taking it all away (including the Mac). Bother.
That meant I had to take my little Powerbook out and spend
a good 15 seconds setting it up with all the IP numbers and
stuff. I'm using one of our "spare" addresses: 199.4.251.66
- now formally on the name-server as poodle.spole.gov. When
the PC comes down it will use the old address of Andre's "penguin":
199.4.251.68.
(Actually,
I'm more than a little surprised the Powerbook still works.
I planned to take it as carry-on, but at Christchurch I was
told it had to go as hold luggage. I packed it up as best
I could, but then watched as they throw the bags into a 8-foot
cubed crate and a bloke stands on top them all and *jumps*
on the ones that stick up so it all fits. At any moment I
expected to see the whole pallet go into a wool press, or
one of those big machines that crunch cars up until they look
like bricks).
What
else happened today? Mainly good stuff. "Crunch"
came in the night and took away our leaking Sonnenscheins,
plus all the lead- contaminated stuff we could find. The solar
dunny is now working, although the liquid soap dispenser is
still frozen solid.
And....
Ant and I are now fully-qualified Sprite drivers. A Sprite
is a bright yellow thing on caterpillar tracks, that you steer
by pulling back on either of two levers. Pulling back on both
levers makes it stop, with the result that the instructor
goes through the windscreen. Sadly, pushing the levers forward
does not make it go faster. It also has all kinds of beaut
gauges and switches, but the instructor didn't what they were
for so we couldn't play with them. Ant was last seen trying
to perfect a Scandinavian flick, but I have my sights set
on the D9.
More
good stuff. A cargoid brought our crates over, and we unpacked
the Abu electronics rack and the mount. A different cargoid
brought the crate containing the G-mount crane over, plus
the crate to ship the AFOS back. The cargoids are entirely
male and hairy, by the way. (I think I've mentioned this before.
This is not good news.)
Oh
yes, the Siemens high-side switch. Totally protected against
everything (including acts of god) *except* for... not having
its ground pin connected to anything. Nasty. I guess it's
hard to do good switching-type stuff if your feet aren't on
the ground (although I'm reminded of the old saying: "If
you've got your two feet firmly on the ground, how are you
going to put your trousers on?) Anyway, it's a favourite trick
of our otherwise excellent electronics workshop to forget
to solder the odd pin on a PC board. My job is to carefully
check they hadn't. I did. They had. But I obviously hadn't
checked well enough until my attention was drawn to that particular
pin by the spectacular burn marks radiating from that part
of the rack. Amazingly, the board had worked perfectly all
last season.
The
nism batteries are now fully charged - the ELGIPS has backed
off to 0.02A, as well it should.
I
climbed up the G-tower to move the AFOS - it was pointing
about 20 degrees above the horizon, and sooner or later the
sun is going to shine into it. There was a steady 20 knot
(about 40 km/hr) wind blowing, according to the SPIREX wind
monitor. Leaning against the rails, there's a strong vibration.
Even the aluminum lattice flooring shakes. However, bravely
standing on the G-mount itself, with arms wrapped around the
AFOS (it's kind of cuddly), vibration is close to nil. It's
very hard to be quantitative, but I'd say sub-millimetre and
about 10Hz. It's difficult to be certain it's vibrating at
all when your parka is trying to tear itself off your body
in the wind. Interestingly, standing on the flooring and holding
on to the hand rail (as any rational person would do in the
conditions), there's a strong vibration. Even then, the actual
amplitude is probably pretty small.
Talking
of weather, it's *awful*. The wind hasn't dropped below 15
knots for days, and is usually around 20. Last night it was
gusting up to 25 knots (about 50 km/hr). There's a huge amount
of blowing snow; visibilty is sometimes down to 100 meters
or less. It's nothing like the conditions we had in January,
when we were sunbaking on the AASTO front porch.
Poor
old Fred is a pale green colour and wishing he'd never been
born. It will probably be a day or two before he can do much.
However, we're expecting Ev Pascall in on tonight's flight,
and he should be able to tell us what went wrong with the
AASTO TEG.
How
on earth did the Phillips cro get back to Sydney? I suggest
we bring it back down again.
Now,
the "super". Thanks for those emails, Michael A.
I had wrongly assumed that updating SUPER.EXE would update
the IP numbers. I tried "ne \aasto\telnet.cfg" (maybe
they were forward slashes), but got "unrecognised command".
Maybe "ne" doesn't work at the SUPER prompt? Anyway,
next I tried to download the file from pharlap, but couldn't
find it. Eventually I took the floppy into MAPO and editted
the numbers directly, and that did the trick.
The
hard disk on super makes a noise like wasps mating for about
two seconds when you start it up. (ok, two wasps in a big
hurry). Then it reports that there's a disk controller error,
throws in the towel, and boots off the floppy instead. We'll
have a look at putting one of the other HDs in. There's one
that says it's guaranteed against shocks of up to 150g (but
it doesn't say anything about -79C or brown slime).
I'd
better go and check if Ant has rolled the Sprite.
Cheers,
John
Tuesday
18th November - Nism up
The
last 24 hours have been particularly eventful. (These missives
are written directly after dinner, when it's impossible to
move for an hour or so until dinner settles.)
Yesterday
evening began with a bang when we fired up the MISM. (Regular
readers will recall that the power supply card in the NISM
had previously been deemed unsuitable for up-firing, on account
of the self-incineration of the high-side switch). Anyway,
we plugged in the MISM and were immediately greeted by the
cheery little red led on the front panel, and the nice bright
green one on the power supply card itself.
It
took a few seconds before I remembered we don't *have* a green
led on the power supply card, a recollection that was reinfiorced
by the clouds of acrid smoke cominng from the vicicnity of
the high-side switch. Things were not looking good for a)
getting anything to work at all b) high-side switches in general
c) Siemens nuclear-bomb-proof high-side switches in particular
c) the reputation of quality German engineering (the only
other German things in the AASTO are the Sonnenscheins).
When
the smoke cleared it became apparent that all that had happened
was that the brown slime had bridged across from the case
of the high-side switch to ground, and was enjoying its last
moments of glory. A quick squirt with general purpose detergent
(unsuitable for food-preparation surfaces), and a bit of a
scrub and everything was right as rain.
The
mism power supply voltages all came up fine, so we tried to
telnet to it but got no response. Then we plugged the mism
power supply board into the nism and fired that up - it looked
happy but we couldn't telnet to it either.
We
measured lots of voltages, peered at the PC104 stack and reminded
each other of how awful it was taking it apart, typed in random
commands to poodle, wiggled connectors, briefly tried to visualise
how beautiful life could be if computers had never been invented,
and packed it in for the night.
This
year we're lodged in the "Elevated Dorm", the blue
building with the satellite dish on top. It is actually very
comfortable - much more room than the Jamesways, *quiet*,
and with the shower and the Head all in the same building.
It's a comfortable temperature (sort of), and even has cupboards
and drawers. The only downside is having to share a room with
Ant...
Also
they got the phone in the AASTO fixed, so now it's a bit safer
working in there. We still haven't got our fire extinguisher
back, despite asking for it at least twice a day since we
arrived. If it does catch fire we can try throwing snow on
it, but 4,000lbs of liquid propane will probably require quite
a bit of snow.
Ev
Paschal was out at the AASTO bright and early this morning,
and got straight to work trying to figure out what had gone
wrong with the TEG. Ev is great. Not only is he a good bloke,
but he had no hesitation in immediately getting out the sponge
and the general purpose detergent and scrubbing down all the
grunge that we'd deliberately not cleaned from TEG so Ev could
look at it. A PhD engineer who doesn't mind getting his hands
dirty is a valuable asset in Antarctica.
Unfortunately
it quickly became clear that the AASTO is totally and utterly
stuffed. The stainless-steel exhaust pipe is corroded through
completely where it goes through the ceiling, and is completely
blocked with green and yellow indescribable lumps of crud.
Ev took photos of it. We could tell things were bad because
Ev kept saying things like "Oh boy". It seems unlikely
the TEG can be fixed this season, but we'll see what ASA can
do. It's amazing that something as inert as freon can be converted
into an unstoppable stainless-steel-munching fibreglass-dissolving
brown-goo-creating circuit-board-illuminating monster chemical
simply by passing it over platinum beads at a few hundred
degrees. Any of the 50lbs of freon that didn't decompose has
by now wandered off to the stratosphere to munch holes in
the ozone layer.
At
about the time we had the AASTO covered in yet another pile
of yellow and white grunge, and were picking up pieces of
what used to be stainless steel and/or fibreglass, in walks
the station manager, station science manager, and health and
safety officer. They stood around for a bit shaking their
heads and saying things like "smells bad" and "might
be mercaptan" and "oh boy", and than left before
anything bad happened to their health. I reminded them about
the fire extinguisher as they left.
We
then pulled the TEG apart, and it's kind of ugly and corroded
inside. Worse, it's full of rockwool insulation, which is
now over everything. Ev says it's not carcinogenic. I believe
it's made out of basalt, but have no idea how. It may involve
soaking rocks in the brown slime they get out of AASTOs.
Now
for the good news. While we were sleeping Michael Ashley crept
out of his bed, telnetted to the "super", and fixed
up the software!! Apparently we'd been using the wrong version.
With
that fixed, instant success! We lit up the nism and immediately
poodle was able to engage it in animated converstation. The
only problem was that all the nism would send back was rows
of little square boxes. To a geek that means only one thing
- baud rate. Being geeks we changed the baud rate of the super
to 19,200 (a figure we chose at random), and sure enough it
sprung into life.
A
quick check out shows: adc bb = -17.8C adc volts = 25.51 adc
amps = 202.6 mA The rotator works, and calibrates. The cooler
works - 96K after a few minutes. Choptest doesn't work. First,
if you ask for 20 seconds it only takes data for two. Secondly,
it gives the numbers you want, even if they're wrong. I think
it's being overly polite. For example, if I set the chop frequency
to something impossible, "choptest" runs and tells
me everything is just fine.
To
attack this problem further we grabbed a Tektronics digital
cro from MAPO (the Phillips having mysteriously re-appeared,
minus knob, back at UNSW), and probed the chopper driver card.
I *hate* oscilloscopes that are more intelligent than I am.
This one is so smart that took me a good half hour just to
figure out that in fact the chopper is working perfectly,
and generating all the right reference signals. The phase-
locked loop works between about 50Hz and 82Hz.
Now
that dinner has settled (home-made bread, spatchcocks, cous-cous,
fresh lettuce, carrot, plus freshly-ground coffee and lemon-raisin
pie), we'll go out and actually see if the detector works.
If so, we'll have scored one out three working instruments
already.
Cheers,
John
Wednesday
19th November 1997 - NISM & MISM alive!
Things are moving right along. Rodney Marks arrived last night,
ready to begin 12 months at the Pole. He'll be looking after
Abu, and already we've pressed him into service lugging things
around. Ev has been busy in the AASTO, and has been sending
messages back and forth to the AGO service crew.
Last
night we got *both* the nism and mism working. The mism was
easily able to detect Ant's hand when he leaned out the door
and waved at it. This not only proves that Ant is alive, but
also that he's warm-blooded. It also gives us great encouragement
that we will be able to leave two working instruments here
when we depart in a couple of weeks.
Firing
up the nism first, we were delighted to find that the Stirling-
cycle cooler switched on immediately, and everything just
worked the way it should. Scanning across the sky gives a
large variation in the amplitude of the signal we see (as
it should). The only problem is that the stepper motor doesn't
have enough grunt to consistently move the instrument - boy
do we have a surprise in store for it.
When
we last talked to the mism (in May), the chopper was refusing
to run above 500Hz. Naturally this was one of the first items
for discussion with it when we re-established contact last
night. Sure enough, 500 Hz. Tops. Maximum. This wouldn't matter
a whole lot except that the entire signal chain is tuned to
1kHz. Figuring that if the mism refused to be phase-locked
then we would refuse to be fazed, we plugged in the spare
chopper-driver board and the chopper immediately locked up
at a kHz, no argument.
This
delighted both Ant and me, as neither of us has any wish to
rip the optics box apart and mess with the chopper motor.
However I do take any electronics failure as a personal affront,
and the chopper driver board must have realised it was well
and truly for it.
The
"super" refuses to talk to the mism on the mism
port, so we're using the nism port instead. This might be
a software problem, or could be related to the fact that the
mism rs232 port is on a different board to the nism. Given
that the AFOS will not be running this year, a very simple
fix is to reassign port 1 to the mism.
The
next step was find out what when wrong with the original chopper-
driver board. (I am dismayed to find that not only is the
oscilloscope smarter than I am, but that the multimeter is
also ahead on points. It's a bright yellow you-beaut Fluke
meter, that Ant insisted I buy because it cost a lot of money.
When I tried to measure a voltage with the probes plugged
into the current socket, it beeped plaintively at me. I'm
not sure if this intelligence, or just instinct for self preservation.
Tomorrow I plan to hold it up in front of the mism and see
if it is alive, too.)
Anyway,
what was wrong with the chopper-driver board was that there
was a tiny little bit of grunge on the board, bridging between
two of the copper tracks. It was sufficiently conductive to
reduce the reference signal below the CMOS threshold, with
the result that the PLL simply ran at a random frequency close
to the middle of its range. We will need to talk to our normally
excellent electronics workshop about the hazards of leaving
grunge on the circuit board.
Actually,
we *had* intended to have all the boards made commercially
once the workshop had done the prototypes. I think I'm going
to vote for doing exactly that during 1998, especially in
view of the brown slime.
Speaking
of which, we ripped the nism off the roof of the AASTO and
sledded it across to the MAPO building. The inside of the
support bracket is covered in the last remnants of brown slime
(actually white slime, being aluminium). Because the nism
was exposed it acted as a big cryo-pump and is now covered
in more than its share of grunge. We'll clean it up tonight
and then fit the *new monster stepper motors* which Andre
tested in the lab and found to be all torque (*and* all action).
By
now we're fairly convinced that what hit the AASTO was a combination
of HF and HCl from the decomposing freon, plus H2SO4 from
the batteries. (Michelle thinks it was aliens, but she's wrong.
The aliens live at Old South Pole Station, and don't cause
any trouble as long as we invite them to Thanksgiving each
year, which we do. I've already been enlisted as a wine waiter
for the occasion). But I digress. The only really nasty in
the above list is HF, which gobbles up human flesh like an
offended alien. Paradoxically, it's *so* reactive that it's
very unlikely for any of it to be left in the AASTO - whatever
it landed on it will already have eaten and been thereby rendered
harmless (or so I believe).
Weather
is still very cold; still windy. They're scheduling 6 flights
a day to try to get the program back on schedule, but only
about half actually get here.
While
I'm typing this, Amnt is cleaning up the nism. That's why
this message is so long. When I finish I'm going to translate
it into French, then type it backwards in morse code, and
then go out and give Ant a hand.
Cheers,
John
Thursday
20th November 1997 - Calm
It
is recommended that, when in Antarctica, you try to learn
something new. I'm sitting here learning "Pine".
Mcba says is better than "mail" and he's right.
Antony showed me how to switch it on. It doesn't use the mouse
but you can move the cursor round with the arrow keys, just
like in the good old days. If you get 4,000 copies of this
message, or if it turns out to be one long line of 1,728 characters
- sorry.
How
wonderful it is to have the wind down to 10 knots - for the
first time since we arrived. Suddenly it's quiet and peaceful,
and it's possible to potter around outside without being instantly
frozen stiff.
After
I'd dashed off my message last night, I of course rushed out
to help Ant clean the NISM. He had been so keen to get started
on it that he'd gone and got a Sprite, and in fact I met him
on the way out to the MAPO building. I guess he must have
driven via Dome C as he was only just arriving when I got
to MAPO; Ant assures me that it was by far the quickest way.
Anyway, together we cleaned the NISM - a truly disgusting
task not for the faint-hearted. By the time we'd finished
we didn't have much enthusiasm left for anything, so we went
and wrote postcards. (Actually we took the Sprite for a quick
fang first.)
Ev
has a nice little digital camera, and has taken shots of all
the damage caused to the AASTO by the propane leak. He intended
to put them on the net so that y'all could see it with your
own eyes. Unfortunately, there seems to be an incompatibility
between his Windows 95 compatible camera and his Windows 95
compatible computer, and the images won't transfer. I don't
know much about PCs, but I suspect he's just used the wrong
font when he set up the C:> system/cam/bios.$ram.config
files. Or it might be just that his PC has the wrong serial
number.
Additional
entertainment here comes from the fact that they've started
digging out the cargo arches in preparation for rebuilding
South Pole Station. This has consisted mainly of using the
bulldozers to carve great gouges in the landscape (snowscape?).
However, they've discovered that the snow is compacted into
ice on the side where the aircraft are, and is too hard for
the biulldozers to penetrate. We offered them a jar of Brown
Slime #1, but this was politely declined. Instead, they're
using *dynamite*. There's a muffled bang and then snow all
over the place. Over the next few weeks the station will come
to resemble something like it was in 1973, before 25 of years
of snow-fall buried it. Should be interesting.
This
morning we busied oursleves installing the heavy-duty stepper
motors in the NISM and MISM. We did the NISM first since,
it was indoors and in bits. This was a moderately straightforward
exercise, once we recalled the bizarre attributes of the stepper
motor code. Our first problem was to be absolutely sure of
the stepper motor rotation direction, since even the Tektronics
oscilloscope was unable to calculate it from first principles.
(The Fluke multimeter took a punt, but got it wrong.) Characteristics
of the code that made this exercise unusually difficult include:
- Calibrate
rotation direction CW or CCW? Goes CCW regardless of what
you type.
- The
limit switches only work if you hit the one the computer
thinks the motor is travelling towards. This is actually
very nasty, as if the motor is going the other way it won't
stop until it tears the cables out. Things that can make
the motor go the wrong direction include:
a).
Me, especially if taking advice from the Fluke.
b) Running the motor at a step rate close to the fundamental
resonance
c) Having one phase fall off.
I
suspect we're running an old version of the stepper motor
code, as I'm sure these things were fixed a while back.
As
expected the rotator works beautifully, and the stepper motor
couldn't care less if the thing is balanced or not. Calculation
shows that if the rotator stalls (eg if it hits a limit switch
that the software ignores), it will exert a lateral force
of 2,000 N on the gearbox and on the teeth of the aluminium
ring gear. I've put my money on the ring gear stripping; the
Tektronics has backed the gearbox shattering at 3 to 1. No
one is prepared to put any money at all on a non-destructive
stall.
We're
running the motor at the minimum current that I'm confident
will overcome the detent torque (oh, how I loathe stepper
motors), namely the same current that we ran the old motors
at. (This also saves us having to change the circuit boards.)
Today
all the rest of the boxes came; ie Abu, the 386 super replacement,
the AASTO manual, and various goodies. All we await now are
the replacement Sonnenschweins, coming as hazardous cargo
(and they don't know the half of it!)
The
Good Will power supply (seriously) that powers the super and
charges the instrument batteries when the TEG is down appears
to have gone belly-up. The left-hand 30V supply won't go above
15V and the right hand supply has "bad" written
across the meter and in any case doesn't work at all. Only
the 5V section seems to still work. However, today the super
started spontaneously booting itself every few minutes for
no good reason, just like it was doing last January. There
are times when good will on its own is not enough, and the
super is now powered up from a Lambda 20V, 3.3A supply. it
will be interesting to see if the super continues to work.
I'm
not inclined to bring the 386 in at this stage, as there's
very little space in the AASTO. The existing super reliably
boots off its floppy, and we'll have a go at the hard disk
in a day or two. We'll bring the 386 in when there's a bit
more room.
On
a triumphant note, it's clear that there's *no* ice inside
the instruments, the blackbody is completely free of ice,
everything moves and rotates like it should, and there's only
a teensy bit of snow that's got inside the yellow cover of
the MISM. One side of the NISM cover split off; Ant has glued
it back together and has it sitting in the MAPO shop weighed
down with a rotary pump, a lathe chuck, and a few hundred
pounds of odds and ends (the side is badly warped - it's not
clear it's going to stick back successfully).
Andre;
thanks for talking to Nick Roberts about the chemicals. We're
bringing back samples - do you think he'd be prepared to look
at them and tell us if its fluoride, chloride or sulphate?
The possibility of sulphate from the batteries is an interesting
one - Ev says the racks look "blacker" than you
get from a standard TEG melt-down.
Thanks(?)
also for the advice that we use the Stromlo MoS2 spray-on
lubricant for the bearings. We fished the tin out and it was
*stuffed*. We've placed it under the ANU poster... Ant found
some teflon-based spray-on stuff in MAPO; seems to work a
treat.
As
a final task we installed the new stepper in the MISM. It's
always a hard decision whether to work outside in the cold
(with all those tiny screws, all different sizes), or go to
the trouble of disassembling everything and bringing it indoors.
We opted for the former - it took hours. Finally, when rotating
the MISM by hand to check the balance there's something "rattling"
inside. Quel horeur! If it's a washer, that's ok. If it's
a lens, that's not so good. Ant says that since the MISM can
see him, that's about as good as it gets. I guess it could
be a piece of CVF. I'm happy to run with the existing CVF,
at least until January.
Ant
put all his clothes on to wash, only to have the water to
the Elevated Dorm fail. He now has a whole collection of wet
clothes. He's taking it well, but seems reluctant to go out
and pull the AFOS off the tower in his pajamas.
Now,
to send this I just do ctrl-alt-delete....
Friday
21st November 1997 - Going backwards
Since
we're clearly getting on top of things in the AASTO, we decided
to start the day by hoisting the Australian flag high above
the green and gold structure. And very splendid it looks,
too.
Today
should have been a good day in which we finished assembling
the stepper motors on the NISM and MISM, boxed them up, and
spent the afternoon doing rallycross in the Sprite. Alas,
it was not to be.
Things
started badly when we fired up the NISM one more time to set
the stepper motor rates. There was a fizzing sound and smoke
started rising from the power supply card. We switched off
in a hurry and pulled the card out, but none of the components
I touched was hot (that's the problem with surface-mount chips
- no thermal mass!) Nothing for it but to plug it in again
and watch carefully. Sure enough, little red sparks and wisps
of smoke, not from the main board (built by our normally excellent
electronics workshop), but from the exquisitely made Maxim
card. The board was still working just fine, and it turned
out once again to be a surface track of black crud. I scraped
it of with a scalpel, and it's good as new. (Ev Pascal, professional
electronics engineer, says it sounds like scraping toast when
we're fixing our boards. It seems he hasn't struck anything
like this previously in his career.)
MORAL:
make sure all the boards have all the grunge cleaned off them.
We
took the moral to heart and carefully cleaned the connector
that couples the stepper motor drive signal to the MISM (all
of the mil-spec coating came off in the process, leaving bare
aluminium). All we did was dunk it in water, then rinse thoroughly
in a trichlor/isopropyl alcohol mixture out of a spray can.
Then
we plugged it all together and... horrors! The clockwise limit
switch ceased functioning. With the stepper motor developing
more torque than a D9 and heading relentlessly for the limit,
we quickly pulled the plug. (Andre: the Fluke takes up your
offer of 10:1 on a non-catastrophic stall, and wants to take
odds on Ant rolling the Sprite.)
To
cut a long story short, it turned out that the plug was still
wet and this was shorting out the limit switch.
MORAL:
After you've washed things, dry them.
It
would be handy if the software command "rotstat"
told you what the limit switch readings were, to aid diagnosis.
Clearly
we need to think carefully about how to clean up the electronics
boards (and connectors) before we can turn our backs on this
thing.
The
good news is that the stepper motors really do have huge amounts
of torque, even at the 114mA "normal power" of the
old motors.
At
the CARA meeting on Wednesday I asked again for a fire extinguisher.
The reponse was that this did not seem to be a very urgent
request, and when did we think we'd really need it by? I suggested
that we'd like it just before the fire started, please. This
scored us a laugh, but no fire extinguisher. Yesterday we
tried a different tactic: we *didn't* ask for a fire extinguisher.
This morning there were *two*, sitting either side of the
AASTO entrance door.
We
now have in our possession "AASTO #1", the first
JAZ disk of housekeeping data. Does anyone in Sydney think
they know how to read it?
Nothing
really funny happened today. I washed my clothes, had a shower
(this is a major event at the Pole), and read my "newt"
email. Ev Paschal fixed the noise problems in the DCU by putting
little capacitors and ferrite beads here and there, and never
once made a sound like scraping toast. The AGO service crew
arrived, looked around and said "Oh boy", and will
come back tomorrow and try to fix the TEG. Ant and I will
work somewhere else, as we alreay know the TEG is full of
rockwool - one of the worst substances in the known universe
after brown slime.
Tonight
the crane is coming to lift GRIM off SPIREX. This marks the
beginning of the Abu project - something that should have
happened three weeks ago. Al Fowler and Nigel Sharpe arrive
tomorrow.
The
"super" hasn't made its "mating wasps"
rebooting noise since we replaced the GoodWill supply with
the Lambda.
The
wind has dropped to below 10 knots, so we hope to get on with
the other tasks like pulling the AFOS down in the next day
or two (thereby avoiding the rockwool).
John
Saturday
22nd November 1997 -
Taking things apart
We,
and others, have mainly been taking things apart. Things are
much less assembled than they were, say, 24 hours ago. Nevertheless,
this is mainly a good thing.
A
couple of emails ago, a few lines got deleted from the middle
my message for reasons known only to the computer. I was saying
that I thought it worthwhile to completely rebuild the electronics
during 1998, as it has taked a real beating. We could take
the opportunity to add a few refinements in order to make
trouble-shooting easier.
Then
for no apparent reason, the computer decided you'd had enough
of that and cut straight to the middle of a story about how
Ant had galantly climbed the G-tower and attached a pulley
so we could haul the crane up. My musings about how cranes
are wonderful apart from the fact that you have to get the
crane up the tower in the first place got truncated.
Great big cranes need less big cranes,
Their
altitude to heighten.
These
little cranes need smaller ones,
And so ad infinitum.
(With
apologies to the person who wrote something similar to explain
microthermal turbulence and astronomical seeing, having ripped
the idea off from someone who was talking about fleas.)
Anyway,
to get the AFOS off the G-tower we need a crane, and the crane
is no longer at the top of the tower because it was removed
at the end of last summer (using gravity assist). So, we rigged
up a rope and pulley and proceeded to the haul the crane up
to the tower. About six inches. After a lot of aerobics we
came to the conclusion that the task was physically impossible,
and set off to find - yes, you've guessed it - a Sprite which
is a good thing, so we could tie the rope onto the bumper
bar (or equivalent) and haul it up. Fortunately we couldn't
find a Sprite, because the pulley was only tied to the hand
rail and, as the Fluke pointed out, we would have simply pulled
the handrail off the tower had we tried.
So
that left us with the AFOS at the top of the tower and the
crane at the bottom, when really we wanted it the other way
round. We contemplated tying the rope aroung the AFOS, passing
it through the pulley and using the crane as a counterweight,
but only briefly.
It
turns out there are two ways to get a big crane up a tower.
One is to use a little crane, and the other is to use a REALLY
BIG CRANE. It turned out that the station crane was going
out to the dark sector yesterday evening to assemble an AMANDA
drilling rig. It was therefore arranged that it would not
only take GRIM down from SPIREX, put the Abu platform up on
SPIREX, and put the G-tower crane on top.
It
was supposed to come at 10pm but eventually started around
3am. By then I'd fallen asleep and took no part in the proceedings,
but I don't think anyone noticed. Ant and the SPIREX crew
worked till 4 and got the whole thing done.
This
morning the AGO service crew arrived and started pulling the
TEG apart. They are serious about getting it going, and have
replaced the platinum beads and the thermoelectric modules.
The TEG is spread over the entire floor of the AASTO. Ant
and I have made a strategic retreat to the MAPO building until
the atmospheric rockwool levels subside.
Now
that the weather is a little better, Hercules flights have
resumed. This makes life seem little more normal, as we're
no longer isolated from the rest of the world. The South Pole
program is weeks behind schedule, so they're scheduling 6
or 7 flights per day. However, typically only two are successful.
Because
the Air National Guard are now flying the planes instead of
VXE-6, the option of using JATO (Jet Assisted Take-Off) is
now available again. Ev says they plan to use it on one of
the upcoming AGO service missions. This is important to us
as eventually we want to put the AASTO on the moon ^H^H^H^H
Dome A.
Walter
Tape is spending a few weeks here. He is the world expert
on ice halos, and is continuing his studies this season. Maybe
I already mentioned that.
Today
the wind was down to 8 knots, so with the crane mounted atop
the G-Tower we tackled the task of bringing the AFOS down.
This was reasonably straightforward, but slow, cold and painful
because the wind decided to pick up again as soon as we started.
The AFOS is now sitting on a sled at the base of the tower,
until such time as we can get some space in MAPO to disassemble
it and pack it into a crate. I hope it doesn't rain tonight.
For future reference, the nut that turns the crane is 1 1/8
inches. I mention this to save future generations of Antarctic
astronomers the frustration of carrying half a workshop's
worth of ring spanners up the tower, only to find that none
of them fit.
Today
we also discovered that the cable we need to instal to run
Abu, and which was ordered weeks ago, is sitting in Yerkes.
It is probably not very useful to them there. However, we've
found a roll down here that will probably do instead.
The
VIPER (Cosmic Microwave Experiment) was unpacked and it was
discovered that the waveguide has sheared off the inputs to
the preamplifiers, no doubt increasing their noise figure
a tad. It's increasing unlikely that VIPER will run this year.
Another
thing that's unlikely to run is the hard disk of the "super"
computer. I plugged in the other 800MB drive and it made happy
little disk humming noises. (This despite the fact that Ev
Paschal who shall remain nameless *dropped* it off the shelf.
Its fall was broken by the fact that it landed on the keyboard
of my Mac. Note to mcba: Macs *do* have their uses) The super
still wouldn't boot from it, but I didn't investigate further
becaue the monitor wasn't plugged in. (It's in a plastic bag
to keep the rockwool out of it). The noise it makes is quite
unlike the mating-wasp noise the original one makes.
Ant
volunteered for "house-mouse" duties today, and
spent a couple of hours washing dishes. His skills were greatly
admired by the cooks, with the result that I believe he will
receive the runner-up award of house-mouse of the week. The
cooks have given us a packet of bi-carb soda to fix our electronics
with. They seemd to think this was perfectly normal, but then,
we are at 10,000 feet.
Al
Fowler and Nigel Sharpe didn't arrive today, which is just
as well becasue we still have about a week's work to do before
we're ready for them.
Micahel
Ashley sent a sample of the stepper motor software to us,
in reponse to our various unsubtle hints that it would be
nice if a few little changes were made to it. This code, you'll
recall was written by a professional programmer. I've come
to the conclusion that professional house painters and professional
programmers belong to the same union. Certainly the code looked
like it had been written by a house painter, probably the
one who painted our carport brown when we wanted it left white.
The
section of stepper-motor code that worried me most was
If
(someone is in the AASTO watching)
{
work properly};
Else
{ stuff up really badly }
Al
Harper has asked to be kept informed of what we're doing here,
so I will add him to this mailing list until such time as
he screams for mercy.
John
Sunday
23rd November 1997 - Good will restored
Yeah,
it turned out all the screws were loose inside, including
the ones that convey electrons from one part of the circuit
to another. When I tightened them up, everything worked again
including the meter with "bad" written on it. This
hardly rates as the major headline event of the day, but it
made a catchy "subject" line.
Actually,
we're finding a lot of loose screws. For example, the screws
holding the ring-gear onto the NISM were finger tight, and
there was considerable slippage. I can't believe we left most
of the screws on our gear so loose, and wonder if the thermal
cycling is to blame.
Last
night I made the mistake of going out to MAPO while Ant was
shovelling snow. I couldn't resist reciting the appropriate
verse from "The Good Ship Venus", which instantly
incurred me the punishment of having to spend the next couple
of hours, shovel in hand, clearing all the remaining snow
away from SPIREX. Meanwhile, Ant and Fred were attaching the
new platform to SPIREX (a job which was completed today).
Fred is from the "locomotive" school of heavy engineering
(the SPIREX azimuth table being made out of 2-inch steel plate,
for example), and there is no doubt that this is one of the
heaviest instrument support platform ever installed on a telescope
smaller than Parkes.
This
morning we sledded the AFOS across to the MAPO building and
spent an amusing hour with the crane (yes, MAPO already has
a crane), lifting things up and down. Eventually we ended
up with both the AFOS and its crate "up" (in the
sense of being inside the building), and some useless piece
of VIPER junk (oops, for a minute there I forgot I'm sending
these messages to Al Harper) down (in the sense of being outside
on the snow). Actually we did ask the VIPER people first.
This made enough space inside MAPO for us to unpack the AFOS
crate, and start putting things in it to ship back to Sydney.
We
began by making a short list of the most revolting substances
known to man:
1.
The brown slime we found in the AASTO
2. Rockwool
3. VXE-6 brown-bag lunches
4. That awful 2-part foam that mcba put in the AFOS crate.
It
is left to the reader to place these in some sort of order.
We
took the primary mirror out of the AFOS and packaged it in
its original cardboard box. It's in great shape. Then we simply
bolted the AFOS back together again, leaving the window in
place. We have great confidence in the ability of the window
cover to provide the necessary protection, but padded everything
well anyway.
We
included the Oriel and CCD, the electronics from the AFOS
(in a sealed plastic bag because its covered in brown slime),
a triangular block of wood that looks terribly important but
we've no idea what it's for, and a plastic bag containing
chemical samples from what used to be valuable pieces of scientific
equipment in the AASTO. I worried a bit about how to get these
through customs, but in the end decided just to put mcba's
name on the box and leave it at that (this is in retaliation
for the 2-part foam).
One
item of some concern is that when we opened the AFOS a little
piece of broken glass fell out. It was very small - maybe
2mm - and at first I thought it was a piece of ice except
it didn't melt. There's no apparent damage to the primary,
secondary or tertiary, so I assume Max just put it in there
as a joke.
We're
really low on fuel here, and they've taken the extraordinary
step of scheduling flights for today even though it's Sunday.
In fact, they've sent 8 of them, all tankers. They've been
arriving all day, but it's very windy and overcast, at times
approaching a complete whiteout. The planes typically have
to do a couple of low passes before they can land, and sometimes
just wander off for half an hour or so while the weather clears.
Six have made it so far today, with the other two still en
route.
Don't
worry about the fibre optic cable ends, Max. We made little
boxes to put them in, then wrapped everything securely in
place.
Andre:
we don't seem to have any male IEC plugs. Did you put them
in, or did you just intend that we steal them from VIPER?
Mcba:
it turns out there are two unused fibres going out to SPIREX.
This will be perfect for the ethernet, and we won't need the
drum of cable that somehow is still at Yerkes. Can you buy
a plug-in ethernet card for the PC with a fibre connector
instead of 10BT? We *think* there is a spare fibre ethernet
port in MAPO for the other end of it; otherwise we need a
10BT - fibre converter box thingy. We'll get back to you on
that.
After
more gear-stress caclculations we've reached the conclusion
that the most likely failure mode of the NISM stepper-motor
drive is that it will crash through the limit switch, wind
the cable up around the elevation axes, drag the elactronics
rack across the floor until the whole AASTO unbalances and
falls over, filling the air intake with snow and shutting
everything down. Should be a minor problem to fix after this
year's disaster!
We
just had a Sunday Night Science Presentation by Jerry Marty
and John Rand (NSF heavies) on the new South Pole Station.
It's a $115m project. (It did occur to me that maybe we could
just flog them Mawson, cheap.) Anyway, it was mainly pretty
dull, *except* for a brilliant synthetic aperture radar image
of the existing station, taken from a satellite in October
this year. It shows all of the subterranean structure, including
the Old Pole Station (where the aliens live), the old runway,
and Pomerantz's old experimental station>.
The
AGO service team have been working hard all today. They've
replaced the platinum beads, the exhaust manifold, the exhaust
shroud, the freon lines, and various things I couldn't identify
but which looked important. They fired the TEG up this afternoon,
but only 4 of the 6 burners came up. They have to leave for
AGO 2 on Tuesday, but are optimistic of getting it all running
tomorrow. As soon as they do, we'll put both the NISM and
MISM on line, and mcba and Max can flog them to death.
Dinner
tomight was steak and giant crab legs, with fresh brocolli
and home made bread.
After
dinner we installed most of the heaters in the Abu box. Every
so often we stick our heads back in the AASTO, but it's still
full of Rockwool and unidentifiable bits of the TEG.
John
Monday
24th November 1997 - AASTO fixed
An
exciting day today with lots of things happening. The AGO
service crew got everything back together again and got all
six burners running. They've repaired the internal chimney
and replaced almost everything else. It was very heartening
to walk past the AASTO at lunchtime and see smoke (or steam)
rising from the chimney. It looked like a friendly country
cottage. The TEG is producing 55 watts, well within spec.
At the moment it's actually uncomfortably warm inside (about
30C). It's likely that the temporary repair to the inside
chimney is insufficiently insulated, and is radiating heat
into the room like a pot-belly stove. We've turned the thermostat
down; in addition added some more lagging. We're very grateful
to Ron Raimbow and the AGO service crew for their heroic efforts.
Ev
Paschal has also put in an outstanding effort, not only with
his help with the initial clean-up and diagnosis, but also
fixing the noise problems in the DCU and calibrating the various
sensor channels. The ARGOS transmitter is back on the air,
and it should be possible to see our signal on the AGO website
(although I haven't checked yet).
The
weather today is fantastic, in complete contrast to yesterday.
Yesterday was windy and overcast, with a lot of blowing snow.
Visibility was only a few hundred metres, and it felt strangely
claustrophobic. It felt like we were wrapped up in a little
ball of cotton wool (or worse still, Rockwool). Today the
sky is crystal clear, a blue hemisphere over a sparkling white
landscape.
The
replacement SoddingSchwein batteries still have not arrived,
so we have taken the spare 20 Ahr PowerSonics from the AASTO.
In addition, the AGO service crew had some other spares flown
up from McMurdo. All of these batteries have been removed
from AGOs that have failed during the winter. (In the case
of the AASTO batteries, they were first frozen in AGO 2, then
again this year in the AASTO!) All are a few years old. I
tested all six batteries, and all six have a capacity of better
than 14 Ahr @ C10 - in other words - almost as good as new!
We will use four of them (don't panic - they're 6 volt units!)
to power up the NISM, while running the NISM off the only
two Soddingschweins to survive the winter.
The
leak in the freon system was found to be in the drain valve
of the freon tank. They tightened the shaft seal, and reckon
it's ok now. I wouldn't trust it as far as I could throw it
- I hope they replace it in January.
I
started wiring up the remaining bits of the Abu heater box
this morning, but Mike Masterman brought me down with a below-the-knee
tackle and sat on my head until I agreed to let him do the
wiring. He and Mark Thoma have been very helpful all day,
and we're quickly making up for the late start to the project
down here.
Fred
has expertly machined the excess length off the dummy T-tube,
and built a very handsome eyepiece holder. It is a reasonably
lightweight flange fabricated out of aluminium. This comes
as a surprise after seeing SPIREX, as we thought he might
insist on having it drop-forged out of a solid tungsten billet.
The
problem of running an ethernet out to SPIREX seems to be solved
now. There are two spare fibres which Mark Thoma says he can
terminate, and Ant used his charm and good looks to score
a couple of fibre-to-10BT boxes.
The
morning concluded with Ant and I rip-sawing large sheets of
plywood to make a base for the Abu electronics rack. We think
we're going to lift the rack onto the roof via eye-bolts in
the plywood base, though the structural integrity of the plywood
is a bit sus. We've found a few pieces of two-by-four, which
we can either use to reinforce the structure or to beat up
innocent bystanders with if the plywood breaks and Abu falls
into the snow.
I
swung past the doctor's surgery and was interested to see
he keeps his implements in the same "Snap-on" brand
tool chest that we use in MAPO for our wrenches and screwdrivers
etc. There's also a large cylinder of "aviators oxygen",
and the radio is powered from an enormous Caterpillar tractor
battery. There's a certian "outback" feel to the
South Pole...
All
eight flights got in yesterday, so the fuel crisis has been
successfully averted. But now an even worse disaster has occurred
- we're out of beer! This doesn't worry me too much because
I don't drink when I'm on field trips, but it's certainly
shaken the Station to the core. As I type there is a group
of people in the kitchen with large vats stirring up some
strange liquid that they probably hope is going to turn into
beer.
Al
Fowler and Nigel Sharp arrived in time for lunch, and have
quickly settled into the routine. Already Abu is unpacked
and is being pumped on the turbo pump. NIgel is a woolly character
who did a postdoc at Stromlo and is going to have to get used
to our Stromlo jokes. Al has grown a beard in the hope that
we wouldn't recognise him, which we didn't.
Does
anyone know why "newt" always waits until I'm in
Antarctica and then crashes? Is it trying to tell me something?
Speaking of computers, and out of fairness to the PC world,
I should mention that the ancient Toshiba T1000 that Jack
left in the AASTO has survived intact. The DCUMON programs
etc are running on it just fine. I spent an hour or two with
Ev while he explained to me how the system works. As soon
as we've lugged the 386 over we'll run DCUMON on it, hook
up some cereal cables (sorry, that should be "serial")
and see if we can talk to it. Ev was able to show me how to
set up the power allocation for the instruments, and how to
limit the data they can store. I think a few milliwatts and
half a dozen bytes per week should be enough for Stromlo.
I can also send 3-line messages (each of 29 characters) out
via the ARGOS satellite, to where they will be received by
a waiting world hungry for data. I can feel some Haikus coming
on.
Tomorrow
we'll vacuum out the AASTO (thereby getting rid of the Rockwool),
have the carpet professionally shampood and maybe get an interior
decorator to give the place the once over. Then we'll be ready
to move back in and *take data*.
John
Tuesday
25th November 1997 - presprespresprespres....
This
morning was spent cleaning the AASTO. By lunchtime it was
inhabitable again, with hardly a trace of rockwool or brown
slime. The bad news for our wives and partners is that we've
spent so much time cleaning over the past two weeks that neither
of us will want to pick up a vacuum cleaner or duster again
for months.
The
AASTO seems pretty healthy, although it's running too hot.
It seems that there's enough heat coming directly off the
TEG and exhaust pipe that even with the freon valves wide
open it maintains about 30C inside. This isn't actually such
a bad thing, as it it means we can work with the window open
and minimise the risk of asphixiation. I'm told that if the
oxygen levels in the room drop too low then the burners will
simply shut down - whether they will do so before or after
I do is not something I want to experiment with.
What
we need is a canary - maybe a budgerigar would do at a pinch.
Sadly,
the AASTO no longer makes whale sounds. It's probably because
the thermostat is wide open and not throttling the freon flow.
The only sound is the gentle roar of the burners, and the
liquid freon trickling back into the storage tank. This has
none of the charm of the whale noise, and instead sounds a
lot like a faulty toilet cistern.
This
afternoon we hooked up the ELGIPS battery chargers to run
off the AASTO bus, so we're now completely self sufficient.
It's a great feeling to sit in the AASTO and realise that
you could just as easily be almost anywhere on the entire
antarctic continent. Come dinner time, though, and you're
glad your're at the South Pole (fresh asparagus, crab and
prawn creole, fresh grapefruit...)
The
sapphire window arrived with Al Fowler. Ant keeps unwrapping
it and looking at it and then putting it away again. A 5"
diameter disc of sapphire is a mighty fine thing. Sooner or
later we're going to have to summon up the courage to bolt
it onto something.
Mcba
- important question: is it possible to make the ACER 386
boot up as a normal MSDOS machine? For that matter, can the
super be persuaded to do same?
It
turns out that the you-beaut fibre-optic ethernet thingies
that Ant charmed out of the communications people belong to
someone else, so we're back to square one on that score.
Another
important question for mcba: is "rotma" a move to
an absolute position in steps or degrees?
This
morning the AGO service crew left on a Twin Otter to AGO-2.
It's an awfully flimsy looking plane after the Hercs. This
afternoon they called back on HF SSB radio to say that they'd
arrived at the site to find there weren't any lifting pulleys
(needed to jack the AGO up above the accumulating snow drifts),
and could they borrow ours. Naturally we were pleased to be
able to help out, particularly after they'd put such an effort
into restoring the AASTO. The pulleys will be flown to AGO-2
in another Twin Otter tomorrow.
It's
amazing how well the various computers, electronics, motors
etc have survived one of the coldest South Pole winters in
history. It seems possible now to make a list of things that
survive freezing and those that don't:
1.
Don't survive:
Sonnenschein
batteries
Some computer disks
People
2.
Do survive:
Everything
else
Did
I mention that we experimented a bit with the stepper motor
rates and came up with the following that work pretty well:
min 200, cal 400, ham 200, max 500, accel 25.
Abu
is pumping down well, and Ant and Al have been rushing around
orgainising things. A potentially serious hitch is that the
fibre link from MAPO to SPIREX is the wrong type, and incompatible
with Abu. At best we'll have to chop the ends off the fibres
and repolish them for the new termination; at worst we'll
have to wait until the right fibres are flown in. Fred is
making the "dog-house" that protects the elevation
motors from the snow. Mark and Mike are hitting each other
with large, heavy things to determine who will have the privilege
of making up more of our cables.
We've
lugged the ACER 386 across to the AASTO, where it taks up
90% of the remaining space. It works, and can be telnetted
to. We'll start incorporating it into the system in a more
permanent manner once we've debugged a few things. It has
an AWFULLY LOUD FAN, which is about to meet with an accident.
This
afternoon one of the Hercs got the pitch control of a propellor
jammed. Their first approach to solving the problem was to
open the throttles and hit "coarse". The resulting
blast of wind nicely cleared the area behind them of people,
bulldozers and other objects not tied down, and sent a snow
flurry rolling across the plateau that could be seen for minutes
later. Their second approach was to taxi aound a bit, *without*
first turning on the flashing red lights that warn you of
approaching aircraft. As I crossed the skiway I looked over
my shoulder to find I was being pursued by a gazillion horsepower
of pure grunt, with four ten-foot diameter people mincers
whirrling menacingly in front of it. This is one situation
where you do not necessarily insist on your right of way.
They must have got it fixed eventually, because it later took
off (though it took most of the 14,000 foot runway to do so).
If
you were a computer and one of your Dallases had ceased to
dangle, you would probably be moved to utter 4-letter words.
However, it's unlikely that "pres" would be one
of them. Nevertheless, when I type "DS INIT" into
the super, it responds with "presprespresprespres...",
and then refuses to tell me the temperature of any of them.
The problem can be fixed by disconnecting the Dallas on the
NISM mounting flange. I assume it's somehow shorting out the
whole chain. We'll look into it - this is the Dallas that
would have copped the full wrath of the brown slime when the
NISM went into brown-slime cryopumping mode.
The
"round the world" race is a Christmas Eve tradition
in which people race around the skiway, taking in all 24 time-zones
as they do so. I'm told it has always been won by runners,
although skiers and mountain bikers have also competed. This
year Matt Newcombe has arrived with a very fine Cannondale
V-500 with Gortex cables and 2.5" wide snow tyres. I'd
say he's in with a real chance.
We
still don't have any alligator clips!!! This is awful. Before
we come down again in January I'm going to buy $400 worth
of alligator clips, and ship them down with "URGENT"
in big letters on the crate. It is impossible to measure stuff
using multimeter probes unless you've got four hands. The
Fluke is so smart it refuses to let you plug anything in unless
it's a safety-approved probe, just in case you electrocute
yourself. (On the "ohms" range???) The result is
that you end up attaching those stupid little clips that someone
send down last year instead of alligator clips to the end
of the probes and dangling the whole thing in space in such
a way that you either blow up whatever it was you were trying
to measure or electrocute yourself anyway.
We
could also use a thermal wire stripper down here.
Other
things we need to buy are:
1.
A labeller - like the one we used last year. Andre - could
you check out the "Brother" catalog please.
2.
A spare Australian flag (Aust. Geog.)
3.
A budgerigar (and perhaps a backup one)
Cheers,
John
Wednesday
26th November 1997 - Sonnenschein noch einmal
There
was an exciting start to the day when at 4:30 am lone figure
was spotted heading out from the station towing a sled and
pulled along by a large parasail. He went for several miles
before setting up camp, just visible with the naked eye from
the MAPO building. At about 8am the station leader sent out
4 people on Skidoos to retrieve him. He was carrying 150lbs
of food (enough for 60 days), a GPS and maps. As it turned
out, he was just testing gear for a future trans-Greenland
expedition, and had forgotten to tell comms. of his experiment.
(That's the official story, anyway.)
Watching
this drama unfold blew most of the morning, but we still managed
to get a fair bit done today. The electronics rack is now
firmly mounted on the structurally-challenged piece of plywood,
and Al has installed the Abu electronics in it. Abu itself
continues to sit on the turbo pump.
Nigel
is busying himself getting the Suns up and running. We've
cut a hole through the floor of the MAPO building to bring
the rather short length of available optical fibre through,
so that tests can be done before it's all installed on the
telescope.
Ant
worked hard to organise a satisfactory mount for the sapphire
window, and then we measured the diameters of the T-tube and
the hole in SPIREX it has to pass through. The depressing
result was 5.06 and 4.99 inches, respectively. Worse, the
heads of the bolts that hold the window onto the tube exceed
the flange diameter by a handsome margin. It's basically impossible
to decrease the diameter of the T-tube, so we looked next
at enlarging the hole in SPIREX.
This
turns out *not* to be a straightforward task. The hole is
in a one-inch steel plate that has been flame hardened (because
it also serves as the friction-drive disc) and weighs around
300lbs. For a while it looked as if the whole project was
about to suffer a major setback, but when we mentioned to
Fred the possibility of some heavy engineering he got so enthusiastic
about removing the disc and flame-cutting a bigger hole in
it that we almost had to restrain him from doing so on the
spot. We were at first concerned that cutting such a hole
might distort the disc - it turns out however that it's bolted
to a *two-inch* thick plate by 12 humungous bolts that will
certainly pull it flat again. There's always been half an
idea to instal a small crane on SPIREX to make such jobs easier,
and indeed we have been contemplating how on earth we're going
to get Abu and its electronics racks installed. The need to
remove the friction disk (if I'm going to use inches, I might
as well call it a "disk") was the final straw that
persuaded us that we needed a crane.
Now
even at 10,000 feet Ant and I both vividly remembered that
a crane ideal for the purpose was currently sitting atop the
G-tower. We remembered that because it was such a hassle putting
it there. It turned out that bringing it down from the G-tower
was a lot easier, as we carefully lowered it with a precisely
controlled acceleration of 9.8m/s-2. The snow drift that had
accumulated in front of the crane crate made for a (reasonably)
gentle decceleration.
We
then sledded the crane across to MAPO, and craned it to the
roof, where Fred is now cheerfully drilling mounting holes
for it in the baseplate using an electric drill the size of
a cement mixer.
This
season is the start of the New South Pole Station construction,
and lots of people are running around with walkie-talkies.
At lunch, when everyone hangs their coats up in the foyer,
all the walkie-talkies in the coat pockets talk to each other.
It can be more than a little disconcerting.
Speaking
of walkie-talkies, Mark and Mike found one on the roof of
MAPO when they were shovelling the snow off. It had been buried
there for months, but when it was brought inside and warmed
up it worked just fine.
The
wakey-wakey boards are now powered up, and working just fine
too.
I've
noticed that the milk this year is a lot better, and is devoid
of that dreadful "silicone-heatsink compound" taste
that makes UHT milk so vile (NB: please add UHT milk to the
list of the world's most revolting substances, in between
rockwool and 2-part foam). Anyway, it turns out they're using
*powdered* milk. It's a vast technological leap forward, and
I must find out what brand it is so I can take it on plane
trips etc.
There's
some good news and bad news vis-a-vis Sonnenschein batteries.
The good news is that our replacements turned up today; the
bad news is that the cargoids *froze* them. Ok, so they didn't
have a Do Not Freeze label on them, but they were clearly
marked "hazardous" in terrifyingly large letters.
Cargoid #1: "Hey, these things look really dangerous;
what'll we do with them?" Cargoid #2: "I know, let's
give'em a really big thermal shock."
Please
can we have last year's cargoids back. We're even prepared
to overlook the fact that they were mostly young, female,
and seriously cute. They were also highly efficient and didn't
*freeze* things.
Given
that Sonneschein batteries are one of only three things known
to man that are damaged by freezing, we should get our hands
on some PowerSonic gel-cells and ship them down in January.
The Soddingschweins will do over summer.
I've
replaced the hard drive on the PC104 super; the old one appears
to be irrevocably stuffed. By the way, this is am awful job!
To get to the screws (phillips head), you have to remove the
floppy drive (flat head screws). To get at them you need to
disassemble the card stack. To do that you need first to remove
the whole shebang from the box (phillips head screws again).
Because it's all mounted on a U-bracket instead of two "L"
brackets, it's impossible to put back together without first
taking the front panel off the rack. GRRRR! It reminds me
forcibly of the first car I owned, which was a British-made
Wolseley. Anyway, it's all back together except it's not screwed
into the box, but held there with residual brown slime.
The
386 ACER is now fired up and playing the role of "super".
The serial cables all join together in the sense of having
the correct "gender", but fail miserably to mate
in a satisfactory manner. This is because the cable-to-cable
joins both have screws, while the cable-to-chassis joins have
screws but no nuts. Connectors need to have an additional
description as well as just male or female - something like
"persuasion" or "preference" or "perversion",
depending on how they like to be coupled to other connectors.
I'm devising an identification scheme based on little ear
rings that the connectors can wear, and will submit it to
the IEEE for ratification when I get back.
Various
software issues have come up which may not be interesting
or even comprehensible to most people, but which mcba will
instantly solve:
On
the original PC104 supervisor, I swapped in the new Seagate
ST9810A. Works fine, except that it comes up with:
AASTO version 2.0 Error table mis-sequenced or duplicated,
code 117 Error table mis-sequenced or duplicated, code 125
Error table mis-sequenced or duplicated, code 140 Error table
mis-sequenced or duplicated, code 235 Error table mis-sequenced
or duplicated, code 10065
Error #117 - unsupported error
The
386 supervisor is up and running, with the nism on port 2
and the mism on port 3. We're running the version of the program
which is on the hard disk. There's a couple of funnies: 1.
With nism and mism both on, and a telnet session from poodle
to each of super, nism and mism, typing "DS INIT"
into the super keyboard gave:
RTKernel Error: Internal SSP: Kernel level greater 5 Int handler:
IRQ 1 Error location: RTKernel exit function
followed
by an irrecoverable crash.
On
another occasion, neither nism nor mism was on, but a single
telnet with poodle was on. This time it gave:
RTKernel Error: Internal SSP: Kernel level greater 5 Current
task: K Error location: 12821
followed
by an irecoverable crash.
Typing
"DS INIT" when there's no telnet session in progress
works fine; it seems like a case of the computer not being
able to walk and chew gum at the same time.
2.
The Nism is running mism version 2.3, Eric 2.2, April 4, while
the Mism is running nism version 2.3, Eric 2.2, April 28!
3. The Mism gives "illegal response" to commands
like "adc amps", but correctly responds to the command
"adc", CR, "amps". Actually, I fixed this
one! The clue came when I typed "analog" and found
that the echo came back as "analo", or worse still,
"anal". Figuring it was a timing problem (aren't
they all?), I set the "delay loops" to 5000 on the
super, and now it works fine. Strangely, the Nism works fine
even without this tweak. (Have I earned myself a "PC
Guru" badge for this one?)
At
tonight's CARA Science meeting we showed up with a couple
of bottles of Californian champagne and a six-pack to celebrate
the renewal of our ARC grant. Perhaps because of this the
meeting was a little more animated than usual, and a good
time was had by all.
I
tried to run the Nism today, but found it had no power. The
MAX471 on the battery charger board had blown, along with
the 3/8 amp fuse in that line from the DCU power bus. Very
odd. We're currently running with the AFOS battery charger.
After
a rocky start, the Tektronics 2440 digital oscilloscope and
I are now getting along just fine. It's been excellent for
trouble-shooting the Dallas temperature sensors, and has even
asked me to sit next to it at the Thanksgiving dinner.
John
Thursday
27th November 1997 - Disaster!
Today
probably would have been a good a day if we hadn't tried to
take some data with the Mism. It quickly became clear that
there was a large signal no matter where in the sky we looked,
and that although the signal varied with postion it was not
in the way it was supposed to. A little investigation, with
Ant waving first his hand and then a soldering iron around
in front of the window, showed that only one beam was present.
That gave two possibilities, both ugly: either something was
blocking one of the beams, or one of the mirrors had fallen
off. Given the glass-rattling-about noises we heard the other
night when adjusting the rotator, the latter and uglier possibility
seemed the more likely.
We
removed the optics plate - a nasty operation to perform in
the cold because the plate has to be lowered an inch or two
and then held while the D-connector is unplugged and the window
heater wires unscrewed from the terminal block. We put the
optics plate in a plastic bag and allowed it to warm up inside
the AASTO for a few hours.
It
turns out that one of the little rectangular beam-steering
mirrors has fallen off. Of the three dabs of epoxy holding
it in place, one has simply dropped off both the glass and
the aluminium (it appears not to haave properly adhered in
the first placce), one has remained attached to the aluminium
plate and the glass but has pulled a big (5mm) chip of glass
out of the back of the mirror, and the other has come off
the aluminium *and* also pulled a chip of glass off the mirror.
The
possibilities now seem to be:
1.
Bring the optical boxes back to Sydney and make proper optical
mounts, returning the boxes in January. This is probably not
practical as we would need complete new sets of mirrors. It's
something we certainly should do before the end of next year,
though.
2.
Re-glue the mirror, using cryogenically rated epoxy. If we
take the second option, we need to realign the optical system
with a laser. This will be time-consuming, but possible. What
we would do is position a piece of paper above the optics
plate at the same height as the outer surface of the window.
Then, set up a laser so that its beam passed through the "intact"
channel and comes out through the centre of the window. Finally,
align the repaired mirror so that its beam crosses the first
one at the paper. Sound ok?
Some
questions for Max:
1.
What is the f number and diameter of the beam as it passes
through the window? 2. What epoxy was used the first time?
3. How critical is the alignment (we've found all the little
shims - we think)
We'd
like to think about it for a day before we proceed - advice
welcome!
Some
other software issues came up with the Mism:
1.
"cvfma" throws the cvf into continuous rotation.
Is cvfma in steps or degrees? Only "steps" is meaningful,
of course. 2. The figures given to convert rotator steps into
degrees appear to be correct. A quick "eyeball"
calibration gives:
ccw beam on horizon ~5,000 steps cw beam at zenith ~15,000
steps box horizontal ~23,000 ccw beam at zenith 30,000 cw
beam at BB 37,000 (assuming of course that there is a ccw
beam, which there isn't)
Can
I stop being depressed now?
It's
possible to cheer yourself up a bit by looking at:
http://141.224.128.11/ago/daily_reports/ago_today.lis
where
you'll see the AASTO data from the ARGOS transmissions (listed
as AGO-A2). All the numbers are complete nonesense until we
send Augsburg the correct calibration file. (Actually, the
wind speed and air pressure are correct, and the TEG volages
are nearly right).
With
mcba's help we got the 386 super set up so that people not
at the South pole can talk to it. It turns out that the gateway
and domain addresses on the hard disc had not been configured
for this location. The 386 super still crashes (or hangs)
if a telnet command has an unsatisfactory result - eg if it
tries to talk to an instrument that's not there.
Before
firing up the Nism again we tracked down the faulty Dallas
problem and checked the limit switches again. I was worried
that whatever had killed the Dallas (assuming it wasn't Larry
Hagman) might be the same thing that caused the limit switch
to go non-functional a few days back. Anyway, the limit switches
are fine (heaps of megohms, says the Fluke) and the Nism fired
up without any problems.
Here's
a rough calibration of where things are in absolute degrees
(ie, using "rotma")
ccw beam peaks at BB ~175 deg (abs) box horizontal ~390 cw
beam hits snow ~670
There's
a good strong signal that does all the right things. However,
looking at the adc readings it's very noisy. Even when the
signal has a s/n ratio of 100:1, the output from "det"
and "detx" is all over the place. I hope the data
acquiistion software is making multiple samples.
"adc
amps" also gives a very noisy result, although this cleans
up when the Stirling cooler is off. It's likely that the current
*is* in fact noisy.
"adc
volts, bb, cooler all give very stable output with fluctuations
of between 2 and 5 ADU.
The
faulty Dallas turned out to be just that. It was the one on
the Nism mounting bracket. Even after I cleaned it in bicarb
soda, washed it, dried it and brushed it, there's still no
response. It's been replaced with another one, which the software
correctly identifies as "no name found". (The Dallas
whose name can not be spoken.)
Occasionally
we get "sbit" as a response when we do a DS INIT,
but we're not losing any sleep over it.
When
I was wrestling with the Dallas I kicked the bucket of sodium
bicarbonate over, and now it's all over the AASTO. (But it's
a hell of an improvement on either brown slime or rockwool,
believe me.) There's an outside chance that when we come back
to the AASTO this time next year it will have grown stalagtites
and stalagmites, and be really quite attractive.
The
evening picked up considerably when we helped Fred unbolt
the 300lb friction disc from SPIREX. Yes, Fred had lifted
the crane into position single-handedly last night, while
we were asleep. Once we got the disk down, Fred lifted it
onto the trolley and wheeled it across the roof of MAPO. (It's
not clear now why we went to the trouble of installing a crane.
It would have been much simpler just to bolt Fred to the platform.)
Preparations
for Thanksgiving are now in full swing (It's celebrated on
Saturday at the South Pole - I'm not sure what time zone that
corresponds to!) The Dome was full of smoke this evening and
no-one was worried - the cooks had just built a turkey smoker
and fired it up (actually, given the beer situation, I suspect
that home-brew bourbon might also be part of the plan).
Abu
is still on the pump; the pressure is slowly going down, as
well it should. Ant leak-checked the T-tube and found it leak-tight,
which is a worry because everyone knows that fluorosilicone
O-rings are slightly permeable to helium. Ant is going to
try a different kind of leak checker, and possibly a different
kind of helium. Actually, Ant just came in very pleased and
said yes, he *had* got the O-rings to diffuse helium. Good
work, Ant. He's also replaced the "warm" O-rings
on the T-tube with Viton ones. They be fine as long as the
heaters don't fail - in which case Abu will leak anyway because
it contains most of the entire Parker O-ring inventory.
I
visited the ham shack in pursuit of someone who could make
up a 25-foot length of 10-base T cable for me, and found the
operator in the midst of a series of 30-second conversations
with a bunch of anonymous people. He seemed to be enjoying
himself, though I'm not sure why. If I get a chance I'll fire
the rig up and see what's out there.
Nothing
else good happened today.
John
Friday
28th November - Feng Shui inthe AASTO
Today
began early for the welder, who used an oxy torch to cut a
bigger hole in the friction-drive disc of SPIREX. I wasn't
around to see this, but I never cease to be amazed at the
precision with which a skilled welder can cut through 1-inch
plate steel. The 300lb disc is now mounted back on SPIREX
(I'm not sure if the crane was used, or if Fred just carried
it up the stairs under one arm), and the holes have been drilled
and tapped ready to mount Abu on it.
We
now have a second ethernet cable made up inside the AASTO,
so we can run both the "old super" (PC104 + brown
slime) and the "new super" (ACER 386 + excruciatingly
loud fan) simultaneously. The ethernet cable is a lurid shocking
pink colour, and completely ruins the interior decor of the
AASTO. We need a Feng Shui consultant to come in and re-balance
the Ying and Yang of the structure. Maybe I'll be able to
successfully telnet into the DCU once that's done.
Speaking
of telnetting to the DCU, I wasted about half a day on that
today. If we try to do it via port 4 of the super, the super
simply hangs and has to be restarted. I supect it's a handshaking
problem. I might try the "start mism" command, which
sends out a character on the RS232 line willy-nilly. One doesn't
like to hassle inanimate objects, but I'm going to have assert
a CTS if the situation doesn't improve. RS232 is without doubt
the most stupid, complicated, arbitrary, ambiguous, brain-dead,
non-standard means of communication ever invented. Horowitz
and Hill have tried to make the whole thing sound amusing,
but in reality they should just line up averyone responsible
for the RS232 mess and shoot them (including the morons who
designed the original PC, and saved 25 cents per computer
by going to a 9-pin D instead of a 25-pin).
The
Toshiba is connected to the DCU via a cable, a gender-bender,
a null modem and a 9-to-25 pin adaptor.
I
also tried running Kermit on the 386 super, but with equally
blank results. It's not clear, however, whether the original
serial ports of that machine still work.
Ok,
problem solved. Serial port four from the Moxan (alias the
octopus) isn't connected to anything. The situation improves
markedly if we pretend the DAU is an AFOS, and connect it
to the #1 port. I can now telnet in and get the same display
as is on the Toshiba. There's still a funny, though: the screen
will toggle into a mode where the *lower case* letters become
Egyptian hierogyphics, and I can't send any command that requires
a lower case letter or a numeral. Thinking that his might
be a misunderstanding between poddle and the DCU over how
many bits there are in an 8-bit word, I tried telnetting in
from pharlap - but got the same result. (Note: a null modem
is required.)
Now,
by connecting to one of the serial data IO ports on the DAU
(no null modem is required), and telnetting in, one gets (in
about 5 seconds):
*3524470233*4524470233*5524470233*6524470233*7524470233*8524470233*9524470233
*0624470233*1624470233*2624470233*3624470233*4624470233*5624470233*6624470233
*7624470233*8624470233*9624470233*0724470233*1724470233*2724470233*3724470233
*4724470233*5724470233*6724470233*7724470233*8724470233*9724470233*0824470233
*1824470233*2824470233*3824470233*4824470233*5824470233*6824470233*7824470233
*8824470233*9824470233*0924470233*1924470233*2924470233*3924470233*4924470233
*5924470233*6924470233*7924470233*8924470233*9924470233*0034470233*1034470233
*2034470233*3034470233*4034470233*5034470233*6034470233*7034470233*
which
is just what we expect. It's the time stamp, every 0.1 seconds,
in the format: 0.1s s s m m h h d d d, and seeing as how it's
coming from the GPS, now's a good time to adjust my watch.
On
a continuing cheerful note, it turns out that the mirror that
fell off the MISM was the only one in all of our instruments
that was attached with epoxy, rather than RTV. It's clear
that in fact the epoxy held pretty well, but that differential
thermal expansion simply tore chunks of glass out of the back
of the mirror. Ant has glued a new (large rectangular) mirror
back on (with RTV), and we'll leave it until tomorrow before
we start the alignment. The mirror is sitting with a spool
of solder on top of it to ensure it properly conacts the alignment
pads. Thanks for all those tips, Max.
There's
a water shortage in the Beaker Box (or Elevated Dorm, as it's
sometimes referred to. Apparently the day crew only fill the
snow melter up once per day, and the beakers (scientists)
are using more than a tankful. A confrontation is looming.
The beakers claim that non-residents of the Beaker Box are
coming in and using the washing machines (because they're
better than the others) and that's where the water's going.
The snow-melter fillers claim the beakers are taking long
showers, and foolishly suggested that the beakers should learn
to drive bulldozers so they can fill the melter themselves.
They were nearly knocked down by the rush of volunteers. Today,
a Sprite; tomorrow a D9!
I
spent the morning caefully checking the NISM, and as far as
I can see it is performing faultlessly. There was a worrying
moment when I found the signal varying wildly for no apparent
reason, but then looked out the windows and saw clouds scudding
by. ("Scudding" is an activity induldged in only
by clouds and by Ant when driving the Sprite.)
Actually
there is one "funny" in the nism, and that is that
the noise on det and detx, as read by the ADC, is higher than
it is on the cro.
Mcba:
does the software just take a single sample, or does it take
a burst at the peak of the waveform, or does it average over
several cycles, or what?
Another
software feature: when I type in "10 (adc det dlys 2)",
it works most of the time but once I got:
Error #238 Can't decode loop count after the first loop. I
take this to mean that the computer was incapable of counting
up to 2, which, given the altitude, is entirely understandable.
The
two beams of the Nism (and yes, there are two!) are particularly
well balanced: with the window covered we get 2.8mV rms from
the "det" output of the signal board.
I
spoke over breakfast to the station doctor about the problems
of dry and cracking skin. He claims that when he goes walking
at high altitude he finds the best thing to take care of cracking
skin is ... superglue! I'l take his word for it.
Only
a couple of Herc flights today, and in fact only a few in
total over the last few days. Fog at McMurdo seems to be the
main culprit. They did manage to get some beer here for Thanksgiving,
for which there will no doubt be many thanks given.
However,
I'm told that they're very short of turkeys at McMurdo, and
the environmental protection people are standing guard over
the local penguins.
We
had a couple of visitors to the AASTO today: a reporter and
the NSF science representative. We may have to instal a visitors'
gallery on the mezzanine level.
When
the AASTO ceiling is +26C and the outside ambient -30C, the
NISM housing is -12C. In other words, the NISM housing is
only 18C above ambient but 38C below room temperature. I think
we need it a lot closer to the room temperature than that.
Looking at the RS cattle dog, a heatsink something like RS
271-864 represents good value in terms of watts/K/$, so how
about a couple of these bolted to either face of the aluminium
door to the NISM?
A
few other things we need are some MAX 471 current-sense ICs
(these are doing a fantastic job of protecting the fuse in
series wth them), some MAX796-EV power supplies (say two),
and some more of the "big" rectangular mirrors from
Edmund (Ant asks - can we get them without that stupid Ed.
Sci. sticker on the back that is a cow to clean off). By the
way, Maxim will send you up to 5 MAX 471's for nothing if
you ask them nicely via their web page. They are indeed cheaper
than fuses!
Tomorrow
is Thanksgiving and most people on the station will take a
holiday Sat. and Sunday. Probably there won't be any flights.
I've volunteered to front up at 3pm to be trained as a drinks
waiter. Ant is serving at the tables. Woe betide anyone who
looks like they were instrumental in the development of the
RS232 standard.
John
Saturday
29th November 1997 - Wine waiter
When
I accepted the position of wine waiter for the Thanksgiving
dinner I had no idea of the enormous responsibilites involved.
The five of us, Prof. Jim Jackson (Boston University), Dr.
Leonard Johnson (NSF Science Representative at South Pole),
a couple of Daves, and me, were inducted into the Exclusive
Order of Wine Waiters and instructed in the finer arts, which
go as follows:
Each
bottle has to be sampled upon opening, when halfway depleted,
and when nearly empty, in order to ensure that only consistently
high quality wine is delivered to the customer. For this the
wine waiters were issued with a standard NSF "taste-vin",
with a capacity of no more than half a litre. As it turns
out, the customers were enthusiastic consumers, and we had
to open and apply proper quality-control measures to a large
number of bottles. We had on offer:
-
A sauvignon blanc from some miserable vineyard in California
- A
chardonnay from the same vineyard
- A
zinfandel from the same vineyard
- A
red Montana "Salyut", consisting of debris left
over from vineyards in Australia, New Zealand and Chile
- The
same red Montana wine (at least as far as I could tell,
given its temperature of +0.1C), but labelled "Timara"
None
of these wines was actually drinkable, with the possible exception
of the Montanas. We kept the whites in a big bowl of snow,
but there seemed to be no convenient way to bring the reds
to room temperature except to drink them. They seemed to improve
with age.
I
lost a bet with Jim that he couldn't tell the difference between
the California white wines - I think he cheated, because the
Zinfandel was clearly pink.
Anyway,
this will be a fairly short report because all the computer
keys have gone a bit fuzzy and seem to all have the same characters
printed on them. Beakers are staggering out of the Dome and
demanding access to a GPS so thay can find their way back
to their experiments.
Actually,
we did do enormously good stuff today. Ant and Al convinced
each other that the T-tube wasn't leaking, put Abu + T-tube
+ mount together, convinced each other again (while still
sober) that it still wasn't leaking, and now it's on the pump
for the next couple of days. By the time they wake up there
should be quite a good vacuum in the dewar.
Meanwhile,
the MISM optics were being re-aligned according to the following
procedure: a laser was set up at a height of 80 mm above the
work surface (ie the height of the chopper hub), and directed
down the centre line of the baseplate. In the absence of an
optical bench, this required use of the #3 bunk in the AASTO,
plus a pile of floppy disks (formatted for PC, of course)
to sit the laser on.
The
lid of someone's perspex electronics components box was set
up on two labjacks at the same height as the window of the
optics box. After carefully measuring where the beam from
the "intact" side of the optics should emerge, I
was shocked and amazed to see it come within 3mm of the expected
position. The "repaired" beam was then adjusted
to also be within 3mm of the nominal center of the window.
Lines
were drawn on the ceiling of the AASTO, from which was measured
the angle from which the beams were emerging from the window
(or electronics box lid, as fate would have it). Eventually
I was satisfied that the new beam passed through the window,
at 45 degrees to the other beam as required. It wasn't terribly
accurate, but it's as good as we can do given that the #3
sleeping bunk in the AASTO appears not to be optically flat.
(This oversight must have slipped past our purchasing people
at UNSW.)
I
hope future generations of AASTO users will forgive me for
the pencil marks on the ceiling, and the perpendiculars that
have been dropped and seemed to have rolled under the bunk
somewhere.
Ant
and I put the MISM back together, under completely windless
coditions. It would actually have been impossible if the wind
had been blowing more than a few knots, given the difficulty
of doing the wiring outside. Fortunately, today was a beautifully
still day, with virtually no wind. It's possible to wander
around in normal "Sydney" clothes, even though the
temperature has dropped to -35C.
Michael
Ashley kindly pointed out that the problem with the NISM signal-to-
noise is that I was using "adc" instead of "sample".
"Adc" takes the instantaneous value of the waveform,
and thus one expects the "noise" to be the full
peak-to-peak value of the waveform. "Sample" is
needed to actually measure the rms value of the signal. The
beaut thing about being at the Pole is that I can blame all
my mistakes on the altitude, yet still ascribe other people's
mistakes to stupidity.
Speaking
of mistakes, in the last email I should have said the null
modem is *not* needed for the DSE but *is* needed for serial
data port. (Note: this error is a result of altitude, not
stupidity).
One
more brain-teaser: if you do a "ds read" without
first "ds init", the computer reads non-existent
sensors and reports their last known readings.
Normal
service will returned after the next sunrise (whenever that
is).
John
Sunday
30th November 1997 - Alice's Restaurant
On the day after Thanksgiving the cooks take the day off,
so this year CARA and JACARA stepped into the breech to provide
brunch for the station. This consisted mainly of omlettes
expertly cooked by Jim, while the rest of us ran around cutting
up leftovers and opening tins of things that go in omlettes.
Vegemite on crackers was provided for those feeling a bit
delicate after the previous night, and the whole event rocked
along to a CD of The Sixties Down-under: the quintessential
sampling of the best rock music a young nation could deliver
30 years ago. The brunch patrons seemed equally divided on
the what was worse - the Vegemite or the music.
Brunch
concluded with a full volume performance of Alice's Restaurant
- to the delight of all those over 40 and the bemused wonderment
of all those under.
Dinner
was provided by the "ASTRO" team. "Ten-metre
Tony's" beef-in-beer stew (option for vegetarians: leave
out the beef) was, frankly, a bit ordinary, but serves well
to prepare me for the horrors of the McMurdo canteen next
week. Ant and Al did a great job of washing dishes etc. -
well beyond the call of duty.
Last
night I attempted to run the MISM for the first time since
we'd reassembled it. Nothing would work and I was unable to
telnet in. A quick investigation showed that one of the inductors
in the power supply was getting very hot - which is surprising
because, as every physicist knows, an ideal inductor cannot
dissipate energy. Either this inductor had decided to choose
this moment to become seriously non-ideal, or it was being
forced to deal with a much higher current than it liked. The
latter theory was soon confirmed by the observation that the
5V supply was being dragged down to 3.5V, which was why nothing
was working. I considered this to be such an unsatisfactory
state of affairs that I went to bed.
Today
we took another look at it, and it quickly became clear that
the 5V line out to the optics box was shorted to ground. Now,
who has been fiddling with the optics box recently?, I hear
you ask. Sure enough, we'd succeeded in bolting the lid down
in such a way that it crushed the wires - a suprisingly easy
thing to do once your fingers are frozen stiff and given that
you can't see the stupid wires anyway. Nothing for it but
to put the optics plate off again, warm it up inside in a
plastic bag, and make yet another repair. This time we made
the wires *really* short - for two reasons: one, so they wouldn't
get caught in the lid again, and two, that was all that was
left of them.
The
fact that the Maxim power supply was able to merrily thump
3 amps into the short, while at the same time raising the
magnetic flux in the inductor to dizzy heights way beyond
its wildest dreams, confirms what a fabulous piece of technology
it is. Tip for today: buy shares in Maxim.
Anyway,
with everything back together again, the Mism *appears* to
be 100% up and running. Ant even stood on a ladder and waved
a soldering iron around to confirm that both beams were there.
There's
still a couple of idiosyncracies of the software that make
it difficult to go much further. For example, "choptest"
reports the correct frequency (nearly - I've no idea how it
can be off by 5% when the same computer is generating *and*
measuring the frequency) for the *first* sample only. Then,
either the chopper decides to spontaneously drop its frequency
by 10Hz, or the software is off with the faries:
choptest Jan 01 03:18:35 CHOPPER_TEST Jan 01 03:18:35 allowable
percentage error? > .1 .1 Jan 01 03:18:37 total length
of test? (seconds) > 10 10 making 5 iterations of 2000
samples; each iteration takes 2 seconds, each sample takes
1.00 milliseconds hit a key to abort 1, ref = 1000.000, actual
= 995.243, delta = -4.757, stdev = 2020.704 2, ref = 1000.000,
actual = 986.054, delta = -13.946, stdev = 2054.730 3, ref
= 1000.000, actual = 986.385, delta = -13.615, stdev = 2056.661
4, ref = 1000.000, actual = 985.540, delta = -14.460, stdev
= 2057.502 5, ref = 1000.000, actual = 985.613, delta = -14.387,
stdev = 2055.884
Next,
attempting to use "sample" generates the following
output: sample 100 Jan 01 03:24:19 TAKE_DATA_SAMPLES value
= 0.000; stdev = 0.000; count = 2; channel = 0 Error #2195
- STS_HWF_PHASELOCK_2 (3)
I
take this to mean that the computer is not seeing the 2xfrequency
interrupts. But does "choptest" use these interrupts,
or the 1xfrequency square wave? I'll check tomorrow to make
sure that all the correct waveforms are actually going into
the computer. Note that all the above is with the chopper
well and truly phase locked.
The
vaccuum in Abu is great (3 E-6 in whatever units these things
are measured in - problably pounds per square inch), and Al
and Ant are preparing to fire up the closed-cycle cooler and
do the first South-pole cooldown. They've got as far as determining
that they need to change a plug or two, or call in an electrician.
Unfortunately, electricians are a bit thin on the ground at
the moment as two of them were booted off the station last
weekend after they had a punch-up. This is a misdemeanour
that results in automatic expulsion. By all acoounts it was
just a bloke thing. For reasons I've never understood, some
blokes, after they'd had a skinfull, instead of becoming warm
and fuzzy and at peace with the world prefer to belt the tripe
out of each other as a mark of affection. Something to do
with testosterone, I think.
Al
Fowler claims you can freeze cockroaches in liquid nitrogen,
and when they thaw out they just get up and walk around. He
says they're good for at least three cooldown cycles before
they start to get a bit wobbly. Can anyone corroborate this?
If not, it sounds like a good honours project - with maybe
expanding the range of experimental animals up to and including
cats (and possibly first-year students).
Michael
A. has been running the nism, and found that the chopper was
very slow to phase-lock. This is a bit odd, as it was doing
fine the other day. When I tried it today, sure enough it
was very marginal. A small tweak on the centre-frequency pot
brought it up to par, but why it should have changed since
the other day I do not know. I'll keep an eye on it. I also
had trouble today getting the "start nism" command
to work, but as soon as my friend the Tektronics Digital Sampling
CRO stepped in to take a look, the problem instantly vanished.
Today
was a little bit more windy, but the station is still totally
peaceful. With no aircraft, no bulldozers, and almost no people
outside, for the first time one gets to feel how isolated
it is here. A few people came out to jog around the skiway
(in preparation for the "Round-the World race), while
others took a stroll along the skiway - an activity best reserved
for days on which there are no flights. Occasionally a beaker
would go scudding past in the Sprite, but apart from the muffled
sound of the diesel power generator all was still.
Tomorrow
the station will spring back to life again. We're hoping Dave
Pernic will arrive - he's one of those thoroughly useful people
who can do anything, including make the mounts for the SPIREX
secondary mirror.
Our
plan is to have Abu on the telescope by Friday. Everyone says
that this is completely unrealistic, but no-one is sure why.
John
Tuesday
2nd December 1997 - The superposition principle
The
day got off to a bad start with the return of the bad weather:
20 knot winds, blowing snow, low visibility etc. Once we got
out to the MAPO building we wished we hadn't: the nitrogen
liquifier had decided to dump a few litres of ethylene glycol
onto the floor, making an unwelcome mess and soaking the boxes
that Abu was sitting on. We wasted a while cleaning it up,
then called the environmental folk over to complete the job.
The
nitrogen liquifier is in any case a useless piece of junk
and should be thrown away. There is a large box labelled "construction
debris" just outside the MAPO building into which it
would fit quite nicely.
In
the foolish belief that everything was more or less working
ok in the AASTO, I decided to move the "super" so
that it and its monitor were no longer occupying the only
flat bit of bench space in the entire AASTO. This required
turning it on its side, disconnecting the Dallases, and hooking
it up to the lurid piece of ethernet cable it had taken me
three days to extract fron the station comms. people. As will
be seen, each of these actions was to have unfortunate side
effects.
1.
Turning the AASTO on its side results in dreadful grinding
and scraping sounds every time it reboots. It's completely
unlike the "mating wasps" noise of the late lamented
PC104 super - more of a mating Galapagos tortoise noise.
2.
The lurid pink ethernet cable didn't work. Naturally we
didn't discover this until it had been carefully threaded
into position and all the cable ties neatly snipped off.
3.
When the super is devoid of Dallases, it hangs for about
30 seconds while it mourns their absence and considers how
to cope with a future life of loneliness. Each time it did
this we thought it had crashed and tried to restart it,
which meant we got nowhere fast.
It's
hard to believe that just moving the super to a new postion
would have so many ramifications. It's just another example
of that important piece of physics: the super position principle.
Michael
logged on from UNSW and was able to download new software
and spend a very consrtuctive few hours debugging things.
The MISM chopper timing problem is apparently fixed by changing
the priority of the interrupt that services the chopper pulse.
Michael also tested the elevation drive motors and found them
to be essentially perfect.
More
worrying, though, was the discovery that the nism cooler would
no longer turn on. This was particularly worrying becausue
it was working just fine yesterday. Once the satellite went
down I turned my attention to fixing this.
It
was easy to establish that everything was fine, but that the
5V control signal was not being generated by the PC104 computer.
In fact, none of the functions controlled by the Diamond Systems
card were working. So, hardware or software? Careful measurement
showed that in fact the outputs were changing by about 5 mV
in response to computer commands, which seemed to exonerate
the software. It was therefore time to disassemble the PC104
stack.
For
anyone unfamiliar with PC104, it is a compact system of stacking
computer cards that resulted from an April Fools Day competition
run by the IEEE for the design of the most irritating and
fiddly little computer cards possible. By the time you're
decked out with the necessary wrist straps, nipple clamps
etc to control static electricity, and have waded through
the brown slime to get at the connectors, it's a very uninviting
task.
Anyway,
the replacement A/D card was installed, found to generate
the right voltages, and...
...it
still didn't work.
Finally,
it turned out that the highside switch, although working,
had decided to convert its input from "CMOS compatible"
to "40 ohms". Presumably this is what blew the A/D
card, since the clown that designed the power supply card
hadn't put any resistors in series with the CMOS outputs to
protect them (4.7k resistors have duly been added). When a
device with a peak current rating of 74 amps decides to lose
it, it's best for other components to keep their distance.
I
washed the old Diamond Systems A/D card in bicarb soda (it
looked pretty bad) and tried it again, but it's clearly taken
a mortal blow.
Later
in the evening I found that the new Diamond systems card was
also dead. As it turned out, we'd been doing all our previous
tests with the original Nism card, the one with the big hole
blown in it by the departing highside switch. Late last night
I put in the "spare" power supply card that had
been sitting on the bench all winter. I'd checked it to the
extent that it was making the right voltages, but no more.
It turned out all three highside switches had their inputs
shorted to ground. Highside switches may have to be added
to that short list of things that don't survive freezing.
Andre: let's grab some highside switches and some cockroaches
and do a back-to-back comparison in our big freezer.
So
two A/D cards were destroyed, and we had no more spares. Then,
Ant had a brainwave and remembered that we'd packed the AFOS
into a crate for shipping back to Sydney but that it was still
sitting in the snow (thank heavens this year's cargoids aren't
too efficient!), and that there was an A/D card sitting in
it.
Ant
grabbed a Sprite, but it wouldn't start. Time out to repair
the Sprite (battery terminals). Then off for a late night
raid on the cargo berm before carrying off the A/D card triumphantly.
The AFOS electronics box was rather crudely repacked into
the crate - removing PC104 cards at -30C is no fun.
Everything
worked fine after that. However the new versions of the software
have a few problems: rotmis no longer works (I nearly tore
the stepper driver apart looking for that one), worse still
cvfmis doesn't work so there's no way to move the CVF.
When
restarting the "unsafe" version it often crashes
during the countdown. It always stops on the number 14.
The
"start nism" and "start mism" commands
appear not to work the first time the super has been powered
up, until the nism and mism have been manually started and
telnetted into. This is a serious problem.
Tomorrow
some Distinguished Visitors are arriving for a station tour,
including Vera Rubin. We will probably have to make the AASTO
look spick and span, and vacuum the carpet one last time.
Now,
the problem of trying to talk to the DCU via port 4. Recall
that it works fine on port 1 - ie pretend the DCU is an AFOS,
set the baud rate to 9600, and no worries. An attempt to use
port 4 results in no response, the telnet session with the
super hanging (permanently), and the keyboard hanging for
about a minute. Once this has occurred, you cannot communicate
with any instrument until the super has been restarted.
Now,
according to Chinese mythology, four is an unlucky number
- the symbol is the same as the symbol for death. Could this
be at the root of this problem? Well, it may well be, because
port 5 works just fine. Rather than solve the problem, I propose
that we use port 5 for the DCU from now on.
I
was so pleased by this that I completely overlooked it later
in the evening. The nism suddenly developed an inability to
communicate, and no amount of resetting it and the super would
give any improvement. It would respond to a telnet by giving
an "AASTO" prompt, then respond no more. It seemed
clear that the CPU card in the nism had died, and I spent
about two hours exploring all other possibilities before tearing
down the PC104 stack and removing the card. It was then that
the light dawned - unplugging the DCU from the super restored
communication immediately.
Be
warned, however, that if you're sitting with a window open
to the DCU it will beep at you every 95 seconds as it sends
off another ARGOS transmission, and scare the willy out of
you.
Andre
- could you please grab a 5m mains extension cord to bring
down.
The
Mism seems to work fine but has a large signal at all elevations.
This is very puzzling. If you block the window completely
the signal goes to zero, regardless of the temperature of
the thing you're blocking the beam with. It's got me beat....
The
AASTO is running with the super, nism and mism powered up.
The DCU is not connected to the super until the communication
problem can be solved. Ther are a couple of dallases only
connected, to stop the super from complaining.
I
hope to leave it that way now...
John
Wednesday
3rd December - The end
Today
was as excellent as yesterday was dreadful. Not only was it
beautifully sunny, but I didn't blow anything up and we even
fixed a few things. We turned everything on in the morning
and, apart from the usual computer crashes, it is still working
this evening as I type. The smell of charred circuit board
and cremated high-side switch has abated to the point where
none of the DVs felt moved to comment on it when they visited
later in the afternoon.
Michael
is making rapid progress on the software and has fixed the
infamous "start nism" command.
At
considerable effort the 386 computer was moved to a horizontal
position again and all the cables re-arranged for the third
time. Michael thought that being vertical might be the cause
of the grinding noises from the disk. It wasn't. However,
it's more convenient to kick it in its new location, and a
swift boot to the side of the case seems to shut it up.
Meanwhile,
major progress has been happening with Abu. The instrument
is now hooked up to the cryocooler - via temporary helium
lines in the lab. It's cooling down well and no problems are
anticipated.
Fred
has removed the SPIREX secondary mirror, and is working on
replacing it with the new lightweight honeycomb mirror.
Dave
Pernic has turned up, and been chained to the milling machine.
The
comms. people (they of the faulty ethernet cable) spent most
of the afternoon trying to figure out why the two Abu Sun
workstations refused to print on "Thing", the SPIREX
laser printer. I tried not to disturb them too much as I wandered
past from time to time to collect output from poodle. Rodney
has acquired all the necessary skills to run SPIREX, and has
been educated in the art of AASTO maintainence. I haven't
said much about Rodney so far, but increasingly he will become
the key person on both the Abu and AASTO projects as all the
rest of us go home and Rodney stays the winter here to keep
things alive.
Ant
has fired up the heaters for Abu, plus the PID controllers
that will stabilise their temperature to something close to
a balmy Tucson day. A couple of minor problems have surfaced,
but nothing that won't be solved by reading the manual. Andre
had taped the manual to the inside of the controller box in
the hope that the controllers would read it and save us the
trouble. Alas, they didn't.
The
Dallas temperature sensors continue to be more trouble than
they're worth, but they're sort of fun to have around when
nothing else is working. There's still a couple of infelicities:
The
dallas "Mism optics box" is wrongly labelled. It
should be "Nism housing (above heat pipe)" or something.
The
dallases in the Mism optics box, when connected, cause the
super to say:
buscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbuscbusc
0
which
is a nice change from "preprespres..." but equally
unenlightening. Chances are we accidentally did them a mischief
when we were repairing the fallen-off mirror. As an interim
measure they have been removed from the circuit.
The
dallas labelled "Nism box battery" is actually "top
of battery chargers", as the wire is too short to reach
the batteries now. It's actually measuring the temperaure
of the super keyboard, which should be fascinating.
Michael:
the PC104 super is fired up (from the floppy disk) with IP
number 199.4.251.65. The DCU is connected to port 1. Enjoy!
I'd be interested to know what's with the Egyptian hieroglyphics,
and why the "numeric" commands don't work. I put
it on the PC104 super so it wouldn't interact with the instruments,
and so you can work on it independently. Note that the PC104
has a functioning 800 MB hard drive, but is not currently
booting from it (for no good reason).
Here's
a short list of things to bring down in January, just in case
we forget:
A decent cro - something like the 2440 would be ace Six Powersonic
batteries Proper documentation (yes, seriously!) New power
supply cards without big holes blown in them Two power switches
for back panels of nism and mism DB25/9 standoff posts for
decent rs232 connection MAX 471 current-sense ICs A couple
of A/D cards Two formatted Jaz discs (did I mention this one?)
A bunch of replacement high side switches, or cockroaches
(depending on which works better) This will be the last missive
from me, as I'm flying out to McMurdo at midnight. There's
nothing funny to write about in McMurdo anyway except the
looks on people's faces when confronted with the canteen food.
Ant
will stay on for another ten days or so, by which time Abu
should be on the telescope and taking data.
The
patient reader who has got this far might have surmised that
the trip so far has been pretty successful, and by and large
immensely good fun. Helping to make it so have been Ant Schinckel,
Fred Mrozek, Bob Pernic, Joe Rottman, Al Fowler, Nigel Sharpe,
Mark Thoma, Mike Masterman and Rodney Marks, plus the whole
crew at the South Pole station (especially the cooks). Special
thanks, too, to the guys at home: the Michaels, Andre, Max
and Mick, for keeping us on the straight and narrow.
******** THE END ********
Thursday
4th December 1997 - New author !
Hi all,
I will endeavour to uphold the standard JWVS has maintained
on action down here at the Pole, but doubt I will attain his
level of wit .....
Today was an almost AASTO-less day for me. Michael was beavering
away on s/w, with little involvement from me. I spent the
day working on Abu related issues.
Firstly, Dave Pernic finished the new flexible cryogenic lines,
so we (Mike Masterman and myself) installed those. Then we
started pumping on the complete length - around 125 feet.
After finding a few finger tight connections, and tightening
the requisite amount ("strip it, back it off half a turn"),
we found the Alcatel could bring a 125 foot line down to 1x10**-3
Torr in less than 30 minutes - but then just plateaued there
for hours without budging a nano-Torr.
After some thought (see below) we decided that it was due
to something outgassing - the most likely substance being
water, which at 0 deg C has a vapour pressure of around 4
Torr - but at -30 it is down to 9 milliTorr. This evening,
after pumping for around 10-12 hours, the pressure was down
to 2.8x**-6, which I think is excellent. We have started on
the second line, and tomorrow morning we will start the fill/purge
sequence with ultra-pure Helium.
(Note:
the Cal 2200 temperature controllers we use for controlling
the temperature of the environmental enclosures is WAY WAY
smarter than the Tektronix scope John was intimidated by -
it may even be smarter than the Fluke. It suggested we check
difference substances for outgassing qualities ..... and it
was right ! Sadly it does not have the Flukes self-effacing
manner ....)
Tonight we started to align Abu. This consists of using a
laser to determine the center of the geometric axis of the
T-tube, and to compare this to where the IR beam is exiting
the T-tube. Ideally you would like these to be the same ......
After much fiddling, we finally achieved the desired result.
This required the use of a number of ancient units of measure,
not used for many years, but which proved ideal for the precision
adjustments required in this procedure due to everyones initmate
familiarity with such such natural units.
For me, the day was slightly broken up by a much needed shower
- 5 days without is enough, or so I'm told by everyone around
me ..... JWVS couldn't wait, and deserted the base last night,
arriving at MCM at 3 this morning, when they are probably
putting the vegys on to boil for tonights dinner ...... and
the smell was probably worse.
In addition, we had another 5:00 pm CARA meeting - at which
nobody was "cased" (not that anyone has paid their
fines yet but .....). The excuses this time were considered
adequate, as several members were involved in a practice disaster,
to see how the fire crew responded. I think most "victims"
have now been found......
The meeting (as was Mondays) was much the poorer for the absence
of Finn, alias Dave Barnaby. Rodney made his best effort to
fill the shoes of our recently departed colleague, and it
is clear he may yet be able to fill Finns role in these meetings
...... though the lack of a personal electronic assistant
is clearly a handicap (I suggest using a PC104 system, or
possibly a Cal 220 controller).
Fred has removed the tertiary mirror and support tower and
we spent some time this evening working out how to mount our
new tertiary mirror. It is a fiddly, but quite tractable problem.
OK, well, I'm sure I did something else today, but can't remember
what, and as it is now midnight, I shall retire. Oh yes, I
have a JWVS replacement - he is a visiting Japanese scientist
examining logistics, base support etc. He is very interested
in the wind generator here, but a little perplexed as to why
that particular style was chosen. He sleeps more soundly,
and does not mutter abuse at the Tektronix, Fluke, and even
the Weller soldering iron in his sleep, unlike my previous
room-mate, who was convinced most electrically operated items
were more intelligent than him, and was last seen backing
away from a kitchen garbage disposal and up the ramp towards
the Hercules with a fearful and suspicious look in his eye.
Cheers
Ant
Friday
5th December 1997 - Weather ?
Well, a most unusual day. The only tine I have seen a complete
reversal of direction on the wind. It is blowing a wimpy 0
- 2 knots from around 160 - 200 azimuth. It has brought with
it a most unusual foggy substance which has cut visibility
dramatically - probably 200 yards max - and is leaving nice
little ice crystals on everything. (But no drifting)
One of the upshots of this was that the 6 Hercules flights
scheduled today have been thrown into complete disaarray (for
a change). The first flight which tried to find the runway
missed nicely - gave the AASTO quite a nice little shake as
it did a low pass hunting for the flags and came directly
over us. Never actually felt the AASTO shake, rattle and roll
before ...... he did a couple more passes before heading back
to MCM.
The next flight did a pass, couldn't find us, and announced
it was heading back in 20 minutes if it didn't clear. There
was a short pause - after which it was announced that MCM
had overridden the pilot, and told them to stay orbiting the
pole for 90 minutes, in the hope it would clear. It didn't.
However just after they left, a Twin Otter announced it was
landing. Runway lights went on, everyone waited .... and waited.
..... and waited... and finally it called in to say it had
landed 2 miles grid east from the Pole, and was slowly taxiing
across the sastrugi (bumpy snow to the uninitiated) to get
to the base. Apparently he had found a clear spot in the fog
(!) and put it down. He is rumoured to have a GPS in his brain
- he has quite a reputation here ......
Well, the rest of the afternoon went along the same lines
- I think we have had 4 flights go back, and the 5th just
did its first pass - no chance. The 6th is about 90 minutes
out, so .....
On a work note, the second Helium compressor line was pumped
all night and came down nicely. So Al and I assembled the
various pieces, and started purging with ultra-high purity
NO2 - sorry Helium. This process went quite well untill there
was a rather large and sudden failure in one of the solder
joints. Dave Pernic has taken it away, and spoken to it sternly
(this may be more effective than a talking to from any of
the of the Tek, Fluke, Cal or in-sinkerators ....) and it
is now being pumped again for another trial. Fred finished
the design of the new tertiary mount, which is quite trickey
as the 3 holes in the back bear little relationship to the
requested dimensions. Dave Pernic will start machining that
first thing in the morning - he may be somewhat delayed by
having to recover from the work I did tonight on these parts.......
I took great joy in witnessing the MISM and NISM taking data
in a nicely automated manner. In fact, at first I thought
the propane burners were about to go into one of their little
undocumented modes (Note to propane burner: do NOT eat Freon.....).
I quickly realised that it was way too smooth and rhythmic,
so I climbed out of the hole I made in the snow when I landed,
refitted the door - and looked up to see a wondrous sight:
the MISM happily doing cute little steps, pausing to examine
the sky above us, then in desperation at the appalling conditions,
taking a few more steps in an attempt to find a patch of sky
which had better characteristics than the bottom of Sydney
Harbour, and which would justify it freezing its (insert favourite
anatomical part here) off. I even had the joy of seeing this
sequence repeated, and to watch almost simultaneous data taking
by both the NISM and MISM. Thank you Michael for all your
work on the s/w (and John for destruction testing so much
of the electronics so we could find the most reliable boards.....)
(Now, I must also point out that there is a strong correlation
between MCBA taking data so smoothly, and the worst weather
we have seen since I arrived here ......)
I also started the search for/assembly of a turbo pumping
system for Rodney to use during winter. It needs to be: a)
portable; b) suckey (in the sense of capability); c) portable;
d) easy to build a box to keep it warm; e) portable.
I have located a few items which are now undergoing JWVS-1287450123-A
(one of the little known US NASA and Military Standards which
relates to destruction testing of components utilising unusual
techniques: eg not connecting some pins, pooring a variety
of acids frequently encountered in space over them, that sort
of thing). I'll test for several days to find a good unit
for next year.
The platform for the Helium lines to coil on has also been
constructed, and we will start fitting it either later tonight
or early tomorrow morning, in conjunction with He line purging.
In this process we will attempt to liberate enough He gas
to lift the planet a significant amount ..... This will take
a fair chunk of time, as all existing cables must also pass
through this new azimuth wrap.
Hmmmm odd ..... I seem to have spent much of the day playing
with Helium lines, gas fittings (there is an unusual metal-to-metal
system being used to join the lines in several places) and
turbo pumps. The euphoria of watching MISM/NISM collect data
automatically rounded the day out nicely.
Ant....
 

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