Re: [PLUG] Anyone get Verizon DSL in the last 12 months?

[Eric <eric@lucii.org>]

You are correct for electric fields.  
Magnetic fields are not stopped by non-ferromagnetic materials.
If Aluminum foil stops the the hum then it's an electric field that is causing 
the problem.  Ultimately, the best solution is distance between the wires if 
possible.

Eric

On Monday 05 September 2005 9:05 pm, Stewart B. Lone wrote:
> Eric wrote:
> | Aluminium foil will not help.  Magnetic shielding must be
> ferro-magnetic (if I
> | recall my electromagnetics course :-P)  Easy way is to separate it by
> some
> | inches or, if you must have it near electric power cords, you can
> shield it
> | with mu metal.  You can get some mu metal from the inside of an old
> | television set if you have a pair of tin snips and a few minutes.  It
> was the
> | metal they used to build the "cage" that surrounded the yokes and the
> neck of
> | the picture tube to prevent interference (either way.)
> |
> | Eric
> |
> | On Monday 05 September 2005 3:21 pm, gyoza@comcast.net wrote:
> |
> |>Doug Crompton wrote:
> |>
> |>
> |>>I use the central filter approach here and it works fine. One thing to
> |>>note however is that these filters are not magnetically shielded. They
> |>>will pick up hum from adjacent power lines. I had that problem and simply
> |>>re-orienting the filter stopped the problem.
> |>>
> |>>
> |>
> |>This might sound silly and look bad, but, would wrapping the filter in
> |>aluminum foil help?
> |
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> Electromagnetics course notwithstanding, I have opened up many a piece
> of comm. type wire with spirally wrapped aluminum foil used for
> shielding. Sometimes also in basket weave configuration[think coax with
> RCA plugs terminating]. However, if you would be uncomfortable with the
> aluminum you could use the copper screening material used for summer
> window screens. The screen holes should work OK For the Hertz that are
> being dealt with.
> 
> Stewart
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-- 
------------------------------------------------------------------------
#  Eric A Lucas
#  ------------
#   "Oh, I have slipped the surly bond of earth
#    and danced the skies on laughter-silvered wings... 
#        -- John Gillespie Magee Jr.
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