Ferrite vs. WI-FI?

I'm wondering if there any sort of ferrite protective device vs. WI-FI..

Though maybe if the laptop where you're working is positioned several feet away from the router, such protection wouldn't be needed..

I've zero experience with the above, and haven't found info anywhere which discusses these points.

Minni

Hmm, I'm not quite sure what you're getting at; I mean, with WiFi, the issue is the radiated signal.  Ferrites are used on cables, to prevent conducted emissions from traveling along them (am I correct, everyone?).

That being said, I have seen some ferrites made specifically for the 2.4-ish Ghz WiFi frequencies.

But wouldn't it make more sense not to use WiFi, or to shield the WiFi router itself in a cage/box or wrap the antennas in something conductive?

(Sorry if I'm jumping into another thread related to something else.)

R.

--- On Wed, 12/30/09, minnimall <[hidden email]> wrote:

From: minnimall <[hidden email]>
Subject: [eSens] Ferrite vs. WI-FI?
To: [hidden email]
Received: Wednesday, December 30, 2009, 7:00 AM







 



 


   
     
     
I'm wondering if there any sort of ferrite protective device vs. WI-FI..



Though maybe if the laptop where you're working is positioned several feet away from the router, such protection wouldn't be needed..



I've zero experience with the above, and haven't found info anywhere which discusses these points.



Minni





   
     

   
   


 



 






__________________________________________________________________
Looking for the perfect gift? Give the gift of Flickr!

http://www.flickr.com/gift/

[Non-text portions of this message have been removed]

Yes ferrite bead and torroids among others are mostly used to suppress RF on cables, but they also make ferrite sheets.


Even at several feet away youll be geting exposed to the radiation from thewi-fi, remember that wifi units can extend their signal far, plus at closedistances youll also be getting the RFI/EMI and AC electrical radiation from the unit itself on top of the actual rf from the wi-fi signal.

It may not be what the original post had in mind, but
if you're in a situation where the wireless transmission is
well shielded (neighbor with shared transformer, with
high metal fence or adobe wall in between) then
possibly the dominant source of Wi-Fi is through the
wires. (I think at those frequencies the common mode
will die out very quick, but if there are widely separated
wires or current loops you can get differential mode
coupling, and this could travel fairly far?).
Most ferrites are not rated above 1GHz I think, but
if you can get some 2.4GHz ones it might help.
HOWEVER, I've read that ferrites generally saturate
(become useless) above 5 amps of current (at any frequency)
in the wire.
That means putting it on your service wires (if you can
get them that big) is a waste unless your power is off
(or you're using less than 600 watts). The obvious
place to put one is on the neighbor's router and computer
power cords, but again if there are wiring errors there may be transmission
from wireless to wire (luckily this should be
easy to filter because of the high impedance; but the filter
has to have a high quality capacitor with low inductance--i.e. short--
leads). If you can measure
an increase in Wi-Fi at your phone then put the ferrites on each
of your phone wires.

But probably more often the problem is from the airborne Wi-Fi.
Bill

On Wed, Dec 30, 2009 at 7:35 PM, cris_aov <[hidden email]> wrote:


[Non-text portions of this message have been removed]