The Stetzer, and most other filters to some extent, work by shorting out
the high frequency range. If there is any high frequency noise the high
frequency current increases between the source and the filter. Past the
filter, the HF voltage and current are reduced.

Good multistage filters also have capacitors that do the same thing, but
they also have inductors that block the noise, increasing impedance rather
than decreasing it. After that they have capacitors that short out the
remaining
HF voltage, so there is still some current.

Also there is a 60 Hz leakage current. In Stetzers this is more because the
capacitance is bigger. That means with a Stetzer there is also increased
magnetic field between the service entrance and the filter. I think if the
power
coming in is clean this would be relatively harmless unless you are within a

couple inches of the wiring. But with dirty power from the outside it's
another matter.
So the right combination of filters at the service entrance and near the
computer
may be an improvement. But again they are no help with common mode, and
usually there is some of that too.

Bill

On Mon, Jul 13, 2009 at 7:26 AM, <paulpjc@...> wrote:

>
>
>
> In a message dated 12/07/2009 14:48:11 GMT Daylight Time,
> rticleone@... <rticleone%40yahoo.ca> writes:
>
> I was talking with my dad about Stetzer Filters last night, versus a whole
> house AC powerline filter (that would filter all the electricity entering
> the house from the outside).
>
> Paul uk - Can anyone give any clues on this one any ggod fliters etc please
>
> [Non-text portions of this message have been removed]
>
>
>


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