Re: Strange 7912AD *EMERGENCY POST*

Laurent Lamesch <jlamesch@...>

Ashton Brown wrote:

Laurent Lamesch wrote: wrote:


And regarding nuclear research, I remember a field engineer telling
me about selling a lot of transient digitizers to the nuclear
research community. They'd put a TD down a hole with a bomb with the
cabling leading to the blockhouse a couple of miles away. They'd
blow up the bomb and the TD would send the signal out of all the
stuff they were monitoring -- about 1�s before it went into total
meltdown -- and then in the blockhouse monitoring station, they'd
wait for the signal to show up and then after it was captured, high-
speed clamps shut the lines down so the the massive EMP that was
right on the tail of the data didn't totally destroy all the
monitoring equipment. But the poor transient digitizers .... they
got to make one and only one measurement in their entire lives before
that serial number ceased to exist. Danged expensive probe!

Concerning 'strange' uses of TDs: I have a problem with a 7912AD
which apparantly has been used in the Sandia National Labs (it has
a Sandia cal sticker from 1993). While repairing the power supply,
I got some fine light brown dust present in the supply on my fingers.
After some minutes I had the impression that the dust warmed my
fingers up, I also had a salty taste in my mouth after working on
the supply. I let the TD run for some time with the case open, and
the TD's fan obviously spread some of that dust inside the room I
normally work in. During the weeks which followed, after being some
hours in the same room, I got a slight headache and nausea unless
I opened the door for letting fresh air in.

The problem is that I neither know if this dust is bad for my health,
nor what to do to find out what the dust is. Does anyone have a clue
what it might be, or has anyone ever seen something similar?

Laurent Lamesch

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I'll try the e-mail response this time; can't get to Yahoo at moment -
and post this later, if it doesn't show up on web:

WHERE is ".lu" ??

RUN, do not walk - to somewhere local where you can borrow a geiger
counter. If you can't find one, I can send you a Monitor4, about the
size of a calculator -- but that will take DAYS - depending upon where
.lu IS. If there is a Radiation exposure .org nearby or even many miles
away: CALL THEM NOW !!!

SWAB your entire body with damp paper towels and put these in Ziplock
bag. Have your family (?) do likewise - it may be a false alarm and
your symptoms (of flu, etc) merely coincidence.. but the salty taste is
hardly likely from 'flu'.

SAVE all dust in a Ziplock bag. *BAG that counter* and maybe tape the
door to that room SHUT, pending more INFORMATION. I spent one career in
physics research / accelerators: you are describing symptoms of a
possibly Bad emitter of betas and gammas - IF>> alphas also are present:

HOPE you did not touch your tongue, eyes with your dusty fingers..
Outside body, alphas are not much of a problem; typ. a piece of paper
will shield from their also massively *greater ionizing power*: they are
Helium nuclei, after all = Heavy.

This is an EMERGENCY SITUATION, IMO and from what you said. I will cc:
this to your e-mail as well as the forum. E-mail me for a phone
exchange, when you get this. Sounds as if you are unaware of some
radiation basics, which you next need to find out.

SAVE everything you had that equipment around since purchase - packing,
RECEIPTS etc - IF your instinct is right and the symptoms too - someone
has made an utterly UNACCEPTABLE ERROR, beginning with SANDIA LABS, who
may be paying your air fare for decontamination. They may be NEXT place
you call, after local help...

In haste,

ex- Lawrence Berkeley Lab.
Hello, thank you for your mail.

So I went immediately to the ministry of radiation protection in
Luxembourg and took the 7912 with me. We dismantled the power supply
there after ckecking the radiation outside the housing, and the
responsible person measured the beta and gamma radiation inside with
a geiger counter. Nothing could be detected except the normal natural
radiation. He took some probes of the dust and put them into a 'low
level counter' which measures the alpha and beta radiation (? the
measurement unit was bq, the instrument is normally used to measure
the 'natural' radiation from elements present in the earth in some
regions), and here too nothing could be detected apart from the normal
background radiation.

Are the symptoms I described typical for a contamination? Do you have
experienced simliar situations, or do you have other experience in this
field? Do you think the measurements I described are sufficient? The
responsible person proposed to make a measurement of the contamination
of the air in my room if I wanted to be really sure about it, but he did
not insist.

Anyway, I'm afraid it seems that I still don't know what the source of
the problem is...

Laurent Lamesch

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