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2002 Mar 26 01:06

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Re: [vox] [OT] Smoothing out the powerline signal?
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Re: [vox] [OT] Smoothing out the powerline signal?

These are partly different issues:

1) A big power using device on a circuit decreases power available to
other devices when it is powered on. This is often seen with TV when it
dims/flickers as a result of your fridge coming on, and is suggestive of
bad wiring, or excession of the power rating for your homecircuits. This
in a place where a UPS can really help and make sure your critical devices
are not impacted by other devices draining power.

2) EMI can be caused by electrons flowing through wires. In addition to
the EM fields that can impact other electronic circuits, it is also
possible to have wires in certain shapes or lengths act as antenna to
produce RF interference too. Of course, elentronix circuits of similar
lenngth can be impacted by receipt of those RF signals, or flow can be
harmed by EMI. UPS wont help much with these.

What you described with multiple devices having problems with a big power
consumer (fridge) - usually not located near a computer (making 2 less
likely as distance leads to a loss of interference by roughly 1/r^2) item
1 seemed most likely.

How close is your fridge to your computer and other devices? 

Also, have seen your exact description from others (TV, Monitor, and DSL
box getting strong flicker when washing machine or fridge started up), but
"fixed" with UPS.

If, #2 is the problem, the suggestion for looking at your fridge is a good

How close is the computer to the fridge?

On Tue, 26 Mar 2002, Erik Mullinix wrote:
> You might be dealing with an electric motor that is not grounded properly.
> I had this issue.. and found out when the motor kicked on the draw on it was
> several times what it normaly is.  This also caused us to loose the
> faithfull toaster. (Heads down).
> Hesp
> > I got an APC UPC.  How would I know it's a model that does what you
> > described?
> >
> > BTW, I do have my monitor plugged into the UPC, but I still get monitor
> > "jerks" whenever the fridge turns on/off.  It's either not the right model
> > or isn't good enough to block the fridge's powerline distortion.
> >
> > -Mark
> >
> > On Mon, 25 Mar 2002, ME wrote:
> >
> > > On Mon, 25 Mar 2002, Mark K. Kim wrote:
> > > > Do you have any brand + model numbers?
> > >
> > > They are by far, not the best, but seem to work with Linux to some
> extent
> > > (now, not so much before) : APC
> > >
> > > Please dont get one from just what I write about them. I seem to recall
> > > other members of this list with more experience in UPS and vendors and
> > > interoperability with Linux. APC was one of those systems considered
> less
> > > than ideal when compared to others.
> > >
> > > > On Sun, 24 Mar 2002, ME wrote:
> > > >
> > > > > On Sun, 24 Mar 2002, Mark K. Kim wrote:
> > > > > > I got a mini-fridge and a small heater in my room.  Whenever they
> turn
> > > > > > on/off, they seem to cause powerline interruptions that affects my
> > > > > > modem and my computer monitor (and who knows what else -- my
> system
> > > > > > unit?).  I'm concerned about them causing damages.  Are there any
> devices
> > > > > > that smoothes out the powerline signal?
> > > > >
> > > > > I'll state the obvious:
> > > > > Get a UPS that converts AC incoming power to DC over batteries and
> > > > > sythesizes its own AC signal.
> > > > >
> > > > > (Not trying to be mean or anything.)

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