Posted by rowster_c on
URL: https://www.es-forum.com/The-Effectiveness-of-shielding-tp1545288p1545301.html

I managed to snaggle a military rugged shielded laptop some
time ago, but only got it working last fortnight due to
difficulty getting some upgrade gear.

Have done recently: bioprotect card intermittent, NDF
regularly, and new laptop. It is my feeling so far that
this laptop is working. There has certainly been a
diminishing of certain signs/symptoms, and I have used
it regularly. While I do know thee NDF is working, I could not have
done this with other
machines. These things cost I think about $15000 when new,
maybe less. I only noticed after a week the gridded
metallic window shielding, which I didn't think was on
this model. You can hose it, throw it in
the mud and hit it with an e-bomb. Haven't measured it
yet but it appears to be tempest or near.

It can be hooked up to 24V batteries with an internal
low noise step down regulator- no noisy switch modes,
only passive devices. Must now rig the cables for that, will
take a month.

I have stripped it half way. It uses the metallic screening
I mentioned and its v well designed for a market item, but
lacks some of the features that we know how to add, but
it has the reproducibility of a market item. My feeling is the
combination of a linear power
supply, with grid (better than fabric and affordable)
and various shieldings will make a good
general purpose monitor as Jaime has done. Additionally
in absence of fiber optics, a 'Ground loop cutter' (based on
something called a ballun I think) is available
to go on a vga video lead. This is a little box that makes the
signal cable carry less noise to the monitor from the CPU.
This machine is fanless and uses a variety of plastic
heat spreaders to distribute the heat which makes the
case very hot to the touch and almost completely silent. Its
made for the desert or everest.

I have a few of these laptops now but only one power supply,
the supplies are expensive, can get more. A number of people
have built shielded
computers and there have been a number of positive results, while
finding reliable responders can be difficult due to symptom
heterogeneity. If I get some more good feedback on this
system from my use, I would be prepared to loan it to someone
with strong well defined symptoms for a low
price of $30, but with a fairly hefty bond, simply as I don't
want anyone walking off with it if it works for them, to see
whether or not it affects their symptoms. In my
experience when no money (not even a nominal fee) changes
hands, something is not taken seriously. If a
number of people exist for whom such systems work, we have
the expertise to deliver v low emission systems to a large
group of people, thus making manufacturers and the general
public available of our requirements. It is remarkable that some
of these
symptoms of tinnitus mimic the sounds heard on sound meters.
With me its flickering on the vision, not computer related.
The previous shielded box I made had a screen that was
too hard to read (I can fix that now) and pointy corners which
probably would
have radiated magnetics. Well I don't know really.

Marc mentioned glass screens. My expensive one always worsened
my symptoms, and I wonder if on a laptop they act as a mirror
reflecting everything at user.

Rowan C out.


--- In [hidden email], "Bill Bruno" <wbruno@...> wrote:
>
> I agree with keeping distance, but I have more like 4 feet.
>
> I've tried some of those glass shields and found they had no effect.
> On one monitor I was successful shielding with "high performance"
fabric
> from lessEMF. But, it's not that easy to see through unless the
fonts
> are huge anyway. And, it was important to drape it so it was not
directly
> touching the screen, otherwise it didn't shield (according to an AM
radio).
>
> Bill
>
> On 10/2/07, Marc Martin <marc@...> wrote:
> >
> > > i know you have mentioned this before marc
> > > but what do you recommend for protection as i would like to
purchase