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Wednesday
26th November 1997 - Sonnenschein noch einmal
From
John Storey......
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
 

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