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Where to buy EM shielding for computer monitors

Protecting your kit from electromagnetic fields

Toytown Germany > Discussion forum > Germany-wide > Life in Germany
Genie
I've been searching all of last night and this morning for a place in Germany that sells some kind of electromagnetic shields for monitors, i.e. some kind of transparent material that acts as a conductor and therefore can serve as part of a Faraday cage for the business end of a monitor.

I've found several places that sell this stuff in the US, such as this and this, but I can't seem to find anything in Germany. I've even called up 5 different people in the Bundesamt für Strahlenschutz ("...ähm, ich kenne mich nicht so richtig aus in dem Bereich, ich leite Sie weiter...") but they don't seem to know either. Anywhere in Germany would work, just to cut down on the delivery times before I ask for delivery from the US.

So I thought I'd ask the wise forum peeps - has anyone bought anything of the kind or might have an idea where to find something like this?

Thanks!
bobD
simply fashon a pirate style hat from tinfoil and bob's your uncle
Gorgo
buy a TFT?

If you're worried about electromagnet fields because of health reasons a tinfoil hat is obviously way better ... I'm never leaving the house without one.
Genie
Unfortunately you can't see through tin foil so it's really not a solution.
Gorgo
simple

Genie
TFTs are too slow for my purpose, I really need a monitor that can run at 300Hz refresh (900 would be better but flexed to the available products on the market).

I did read about an interesting technology called Blue Phase that would make 240Hz LCD monitors available, but Toshiba will only market them in 2011, which would be too late for me.
Genie
Thanks to all those trying to educate me in what I need or do not need for my monitor. I assure you, this is something I cannot work without so please spare the condescending "advice" about my FUD anxieties.
BadDoggie
I wrote about this a couple of years ago.

QUOTE
I went digging on the Web and found some explanatory stuff about the actual amount of radiation emitted and how the strength falls off as an inverse proportion of the square of the distance from the source. By the time the 100 or so micro-Tesla (µT) reach him more than three meters away, the current density has fallen from around 10 µA/cm2 to less than 1pA/cm2.

QUOTE (Genie @ Aug 13 2008, 3:06 pm) *
I've been searching all of last night and this morning for a place in Germany that sells some kind of electromagnetic shields for monitors

Perhaps because scammers are nailed pretty quickly here.

QUOTE
I've even called up 5 different people in the Bundesamt für Strahlenschutz

The BfS doesn't deal with poppycock, they deal with actual radiation. From their own site (in English, no less!):

QUOTE (BfS -- http://www.bfs.de/bfs)
X-ray diagnostics in medicine, safety in the handling of radioactive substances in nuclear technology and the protection against enhanced natural radioactivity. The work in the field of non-ionising radiation includes the protection against ultraviolet radiation and the effects of mobile communication.

Said effects being... zero, but it gets them additional funding so they're happy to continue the charade.

That said, if you really want to continue being ignorant and really feel you have to throw away your money I'll be happy to sell you some shielding.

woof.
Johnny English
Him say:

http://www.direct.ca/trinity/elf.html

QUOTE
Shielding. It would be nice if we could purchase a radiation shield for our monitors, similar to the antiglare shield on the market. Unfortunately none exist. Be very careful, there are some antiglare screens on the market that make a claim of blocking the electric and magnetic fields given off from the monitor. First, electric fields as far as I know have not been reported to have any negative impact upon health. Second, the magnetic field the screens claim to block are in fact the visible-light frequency fields generated by the CRT. Those high-frequency magnetic fields have not been shown to have a negative impact on health. These antiglare screens have no impact on the low-frequency (60-Hz) magnetic fields that I am talking about. There is no easy way to shield that monitor to reduce the propagating ELF fields. I have tried a number of different methods, none had any appreciable impact on the ELF radiation. The best recommendation is to keep the monitor 18-24 inches away from yourself.

Another possibility is to use an alternative type computer monitor. Liquid crystal display (LCD) and plasma display monitors do not emit ELF fields. However, their drawbacks are higher cost and lower resolution.
Genie
Thanks for your condescending remarks BD. I'm not sure why people think I need this because I want to protect my health, perhaps this is just self-projection and so it makes people feel smug and all warm inside thinking they're so smart while others are so stupid.

So let me reiterate - please do not educate me on why I don't actually need this, and how this is poppycock and how ignorant I am. In fact, the ignorant side here (and arrogant, and besserwisser, and pathetic) is you, who has absolutely zero knowledge about why such a thing would be useful to me. If you're willing to spare the time and MVV tickets, I'll invite you over to see a live demonstration of the reason I need to "throw away my money".

You also mention that you'd be willing to sell me such a thing, please PM me with the details then. And BTW if I discover you're trying to fraud me I will take the necessary measures to ensure you regret it.
Johnny English
QUOTE
And BTW if I discover you're trying to fraud me I will take the necessary measures to ensure you regret it.


Popcorn delivery needed please over here.
BadDoggie
QUOTE (Genie @ Aug 13 2008, 3:52 pm) *
Thanks for your condescending remarks BD.

Always glad to help out.

QUOTE
I'm not sure why people think I need this because I want to protect my health

Perhaps because everyone who talks about EMI shielding without specifying some sort of reason such as interference from another piece of equipment does so in the fear of Evil Electromagnetic Waves.

Monitors are already shielded and required to be in order to obtain CE and FCC (47 CFR, §2(15)) approval for sale. Perhaps if you wrote exactly what sort of shielding you're looking for and for what purpose you'd get a answer you find to be more helpful from one of the half dozen or so people here who are familiar with RF/EMI.

Update: so the problem is with speakers distorting the picture? Them's what you have to shield, not the monitor. Attenuation needs to be done as close to the source as possible.

woof.
Kätzchen
QUOTE (Genie @ Aug 13 2008, 3:52 pm) *
I'm not sure why people think I need this because I want to protect my health

because it seems like the most obvious use for it and you haven't told us the actual reason as to why you want it?
Kommentarlos
Nice attempt at a back track but no cigar rolleyes.gif
Genie
QUOTE (BadDoggie @ Aug 13 2008, 4:09 pm) *
I'm not sure why people think I need this because I want to protect my health

Perhaps because everyone who talks about EMI shielding without specifying some sort of reason such as interference from another piece of equipment does so in the fear of Evil Electromagnetic Waves.

Well, you should know me better then.

QUOTE
Monitors are already shielded and required to be in order to obtain CE and FCC (47 CFR, §2(15)) approval for sale.

This is a custom made monitor and I'm not sure those clauses hold. Anyways it's from the US, although I'm sure there are equivalent laws there as well.

QUOTE
so the problem is with speakers distorting the picture?

Not quite. I'm using a high-ohmic electrode to record signals, and this recording takes place about exactly 138mm in front of the screen, which means I'll pick up even weak EMFs. I can shield it with a double steel net but this is suboptimal because it distorts the picture and unnecessarily pixelates it, including Moire patterns from the non-aligned net. The best solution is to put a metal-impregnated glass screen or transparent film in front of the monitor, which would reduce brightness/contrast but at least do so uniformly.
Johnny English
Amazing what you can learn from googling.

Peeps could well be worried about "Van Eck Phreaking". In a nutshell naughty peeps can capture your screen data from several hundred meters away!!!

http://searchsecurity.techtarget.com/sDefi...i550525,00.html

Or could also just be working in an electronics lab where the stray EM Fields screw up equipment (like when your mobile phone rings and buzzes on the stereo etc).

So in his defence - he never said anything about health issues!!!

Edit: Aha - truth has outed!
space
I work with electro magnetic fields daily. They can make a CRT monitor seem like it is on LSD with strange colors and wave forms. I asked my coworkers and they are not aware of anything on the market in Germany. Just the usual response like putting a Faraday wall up and or moving away from the source. Another interesting thing is that electro magnetic fields can be reflected, focused even.
Take care,
space
BadDoggie
This is a custom made monitor and I'm not sure those clauses hold. Anyways it's from the US, although I'm sure there are equivalent laws there as well.
That would be the "47 CFR, §2(15)" I referred to, applicable to all electrical devices manufactured and sold in the US which may emit any sort of radio frequency interference.

this recording takes place about exactly 138mm in front of the screen
And you can't move it further away which means your only option is

to put a metal-impregnated glass screen or transparent film in front of the monitor, which would reduce brightness/contrast but at least do so uniformly.
So you already know the answer to your question.

I'm going back downstairs to help tourists understand how to use the parking meters.

woof.
Keydeck
QUOTE (space @ Aug 13 2008, 4:21 pm) *
Another interesting thing is that electro magnetic fields can be reflected, focused even.

You, Sin and Don Riina need to get your arses into a lab and not come out until you have come up with a fully functional light saber.
fRe4k
QUOTE
Peeps could well be worried about "Van Eck Phreaking". In a nutshell naughty peeps can capture your screen data from several hundred meters away!!!

Phreaking is a much older concept than hacking (Obviously..because telecommunications existed long before the computers and software stuff were invented and actively used). On the flip side, its a bit hard to phreak around, just because you need to deal with hardware stuff (buying, setting up, et al things).

There's also a site dedicated to this kinda stuff. A couple of years back, when I was in the univ, I used to read a bit about all this stuff, on the posted underground e-zine site. But its hard to implement, as you need all that hardware stuff.
Genie
QUOTE (BadDoggie @ Aug 13 2008, 4:24 pm) *
And you can't move it further away which means your only option is

to put a metal-impregnated glass screen or transparent film in front of the monitor, which would reduce brightness/contrast but at least do so uniformly.

Ah, finally there is light. Yes, I realize that's my only option, I've been realizing it since I was confronted with the problem. My question wasn't what I need or why I need it, but rather where in Germany could I get it. I judge from your answer, you don't know either.

So, I turn this answer to the rest of the public then - anyone know where to get this stuff?
AnswerToLife42
You already checked this site?
http://www.abschirmung.de/Abschirmung.htm?...CFQtNtAodclp2Yw
Genie
That site is great, thanks!
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