Re: EMF Shielding -Reply

[Wes Van Pelt <VanPeltW@IDT.NET>]

Bill Stephany wrote:
> 
> Aluminum foil makes a great e-m shield.  How you will have to place it
> to
> reduce the interference depends on too much to go in to.  Since this
> process is a "black art" trial and error seem fitting.  Wrapping any
> cables
> you suspect of pick up, even the monitor itself assuring air flow is
> not
> restricted, might do it.  If the pickup occurs in the power line, wrap
> it and
> see what happens.  Probably need to ground the foil.  No guarantees,
> just
> a suggestion based on some memorable experiences which hastened the
> availability of Prozac.
> 
> Bill Stephany
> fiss.bstephan@mail.mcg.edu

Bill,

Al foil will not absorb or deflect the 60 Hz magnetic fields which cause
jitter on computer monitors.

Al foil can attenuate electric fields quite well, but that is not what
is causing the problem. Its the magnetic field.

At a frequency of 60 Hz, the wavelength of the em field is 5,000,000
meters. Clearly we are in the NEAR FIELD in which the electric and
magnetic fields are not coupled and behave independently.

Certain nickel alloys "absorb" the magentic field lines efficiently, but
you need more thickness than a typical "foil".

Prozac??

Wes
-- 
Wesley R. Van Pelt, Ph.D., CIH, CHP                KF2LG
President, Van Pelt Associates, Inc.     
Consulting in radiological health and safety.
mailto:VanPeltW@IDT.net        
http://shell.idt.net/~vanpeltw/index.html