noise from other appliances

Be careful not to plug in too much into a battery backup. Those speaker
systems with subwoofers can draw a lot of watts (but only if the volume is
turned up high). Also, printers should not be plugged into battery backup
for this reason.

In addition to battery backups and surge strips, you can also try different
outlets. I believe the ultimate problem is that you have too much plugged in
on one circuit (look at your circuit breakers). Normally you have your
"kitchen appliances" on a dedicated circuit and at a higher voltage (220v
?), while your normal outlets are 110v or 115v (in the US anyway. Also,
older appliances tend to use twice as much juice as newer energy efficient
ones. Not really anything you can do about it, but just thought I'd mention
why this happens.

-Max


"Skeleton Man" <invalid RemoveThis @guestwho.com> wrote in message
news:Au%Wc.7121$D7.4411@news-server.bigpond.net.au...
 > Hi,
 >
 > I just got a new set of speakers (logitch z-340), and they seem very
 > sensitive to electrical noise (my old speakers weren't).
 > Every time the motor on my fridge cuts in or out (or someone turns a light
 > on or off), then I get a distorted clicking noise through the speakers.
 > The
 > noise only lasts half a second, but it's annoying !
 >
 > Any suggestions on fixing this ?
 >
 > Regards,
 > Chris
 >
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

 >In addition to battery backups and surge strips, you can also try different
 >outlets. I believe the ultimate problem is that you have too much plugged
in
 >on one circuit (look at your circuit breakers). Normally you have your
 >"kitchen appliances" on a dedicated circuit and at a higher voltage (220v
 >?), while your normal outlets are 110v or 115v (in the US anyway. Also,
 >older appliances tend to use twice as much juice as newer energy efficient
 >ones. Not really anything you can do about it, but just thought I'd mention
 >why this happens.

Moving outlets wouldn't make much of a difference.. lights are a seperate
circuit to power, but flurecents still interfere when switched on or off..
(other lights have less effect)..

In Australia we have 240V for everything (appliances operate from anything
around 220V)...
The stove and oven are on a dedicated 30A circuit, with the outlets on 10A.

The kitchen + the outlet I use for my PC (and 1 or 2 others) near the
kitchen make up 1 circuit, with the laundry and lounge contibuting to
another, along with a couple for the bedrooms..

I've experienced the too much on one circuit issue before.. the kitchen,
lounge and laundry all used to be a single 10A circuit.. (with the breaker
tripping every 10 mins!)

I'm not inclinded to buy a UPS, as it's a coupla hundred bux just to keep
the PC up for a few mins to save stuff ! (plus it's a waste of energy
storing 12V, converting back to 240V, only to drop it back to 12V and 5V in
the psu.. It'd be more sensible to run a 12V psu from a car battery, with a
trickle charger attached.. (unless there's a better way?) )

Regards,
Chris<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

"Skeleton Man" <invalid.DeleteThis@guestwho.com> wrote in message
news:BQiXc.7923$D7.4041@news-server.bigpond.net.au...
  > >In addition to battery backups and surge strips, you can also try
different
  > >outlets. I believe the ultimate problem is that you have too much plugged
 > in
  > >on one circuit (look at your circuit breakers). Normally you have your
  > >"kitchen appliances" on a dedicated circuit and at a higher voltage (220v
  > >?), while your normal outlets are 110v or 115v (in the US anyway. Also,
  > >older appliances tend to use twice as much juice as newer energy
efficient
  > >ones. Not really anything you can do about it, but just thought I'd
mention
  > >why this happens.
 >
 > Moving outlets wouldn't make much of a difference.. lights are a seperate
 > circuit to power, but flurecents still interfere when switched on or off..
 > (other lights have less effect)..
 >
 > In Australia we have 240V for everything (appliances operate from anything
 > around 220V)...
 > The stove and oven are on a dedicated 30A circuit, with the outlets on
10A.
 >
 > The kitchen + the outlet I use for my PC (and 1 or 2 others) near the
 > kitchen make up 1 circuit, with the laundry and lounge contibuting to
 > another, along with a couple for the bedrooms..
 >
 > I've experienced the too much on one circuit issue before.. the kitchen,
 > lounge and laundry all used to be a single 10A circuit.. (with the breaker
 > tripping every 10 mins!)
 >
 > I'm not inclinded to buy a UPS, as it's a coupla hundred bux just to keep
 > the PC up for a few mins to save stuff ! (plus it's a waste of energy
 > storing 12V, converting back to 240V, only to drop it back to 12V and 5V
in
 > the psu.. It'd be more sensible to run a 12V psu from a car battery, with
a
 > trickle charger attached.. (unless there's a better way?) )
 >
 > Regards,
 > Chris
 >
Ummm not sure what costs are over there...but you can buy a UPS here
starting at $30. So not exactly a HUGE investment, and you don't need
60mins of shut down tme, something with 5 min is usually enough.

-Chris<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

Skeleton Man wrote:
 >
.... snip ...
 >
 > I'm not inclinded to buy a UPS, as it's a coupla hundred bux just
 > to keep the PC up for a few mins to save stuff ! (plus it's a
 > waste of energy storing 12V, converting back to 240V, only to
 > drop it back to 12V and 5V in the psu.. It'd be more sensible to
 > run a 12V psu from a car battery, with a trickle charger attached..
 > (unless there's a better way?) )

Most do not use the battery until a failure occurs, which means
the cutover has glitches. The system PSU can normally handle
those.

The expense can also be much smaller. I use one that I picked up
at a closeout sale for about 30 or 40 USD several years ago. It
holds up my system for about 5 to 8 minutes, which is adequate to
get it shut down. Abrupt shut down can cause irretrievable
foulups in file systems, and I value my data.

It has only been needed once in the past few years, last spring
when a tree fell across our power lines and brought down two
poles. We had 4000 V (live) lying about in the middle of the
street for a while. Later we went and looked at the damage, and
noticed the poles were rotten through and through. Some evidence
there showed that they were at least 50 years old! I have noticed
this summer that the power company is replacing poles in the whole
area.

--
Chuck F (cbfalconer@yahoo.com) (cbfalconer@worldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net> USE worldnet address!<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

"CBFalconer" <cbfalconer.TakeThisOut@yahoo.com> wrote in message
news:412DDD26.8D111A8A@yahoo.com...
 > Skeleton Man wrote:
  > >
 > ... snip ...
  > >
  > > I'm not inclinded to buy a UPS, as it's a coupla hundred bux just
  > > to keep the PC up for a few mins to save stuff ! (plus it's a
  > > waste of energy storing 12V, converting back to 240V, only to
  > > drop it back to 12V and 5V in the psu.. It'd be more sensible to
  > > run a 12V psu from a car battery, with a trickle charger attached..
  > > (unless there's a better way?) )
 >
 > Most do not use the battery until a failure occurs, which means
 > the cutover has glitches. The system PSU can normally handle
 > those.

Personally, I think that it does make sense to build the battery backup into
the PC itself, after the voltage conversion has been done. It would make
the PC a lot heavier and cost a bit more, but it should be cheaper in the
long run.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

On Thu, 26 Aug 2004 14:57:06 GMT, "Noozer" <dont.spam.RemoveThis@me.here>
wrote:


 >
 >Personally, I think that it does make sense to build the battery backup into
 >the PC itself, after the voltage conversion has been done. It would make
 >the PC a lot heavier and cost a bit more, but it should be cheaper in the
 >long run.
 >

Could be true but how are you going to power monitor/etc, have
every device with it's own UPS inside?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

You are suffering from noise - a tiny voltage of higher
frequency carried on AC mains. Any decent power supply would
eliminate noise from AC mains. Apparently your Logitech
speaker system does not have a good power supply - permits Ac
mains noise into speakers.

One could install an AC mains filter that should have been
inside that power supply. An example:
<a style='text-decoration: underline;' href="http://www.cor.com/catalog/filters/AQ/schematic.htm" target="_blank">http://www.cor.com/catalog/filters/AQ/schematic.htm</a>
<a style='text-decoration: underline;' href="http://www.cor.com/catalog/filters/AQ/Default.htm" target="_blank">http://www.cor.com/catalog/filters/AQ/Default.htm</a>

Another possibility is to quash the noise at the switch that
causes the transient.

Rather embarrassing is the plug-in UPS recommendation. A
typical battery backup UPS (under US$400) simply connects
output directly to AC mains when not in battery backup mode
(they do not convert to 12 volts then convert back to 240
volts when not in battery backup mode). Furthermore, many
such UPSes are extremely noisy in battery backup mode. So
noisy that they may even harm so some electric motors. But
such UPSes in battery backup mode can test the integrity of
that Logitech power supply.

The problem is with those Logitech speakers. Alternative
are to either replace those speakers with a better design,
install an inline filter such as a power entry module or
something from the above example, or modify the offending
appliance maybe with snubbers on the switch.

Skeleton Man wrote:
  >> In addition to battery backups and surge strips, you can also
  >> try different outlets. I believe the ultimate problem is that
  >> you have too much plugged in on one circuit (look at your
  >> circuit breakers). Normally you have your "kitchen appliances"
  >> on a dedicated circuit and at a higher voltage (220v ?), while
  >> your normal outlets are 110v or 115v (in the US anyway. Also,
  >> older appliances tend to use twice as much juice as newer
  >> energy efficient ones. Not really anything you can do about
  >> it, but just thought I'd mention why this happens.
 >
 > Moving outlets wouldn't make much of a difference.. lights are
 > a seperate circuit to power, but flurecents still interfere
 > when switched on or off.. (other lights have less effect)..
 >
 > In Australia we have 240V for everything (appliances operate
 > from anything around 220V)...
 > The stove and oven are on a dedicated 30A circuit, with the
 > outlets on 10A.
 >
 > The kitchen + the outlet I use for my PC (and 1 or 2 others)
 > near the kitchen make up 1 circuit, with the laundry and
 > lounge contibuting to another, along with a couple for the
 > bedrooms..
 >
 > I've experienced the too much on one circuit issue before..
 > the kitchen, lounge and laundry all used to be a single 10A
 > circuit.. (with the breaker tripping every 10 mins!)
 >
 > I'm not inclinded to buy a UPS, as it's a coupla hundred bux
 > just to keep the PC up for a few mins to save stuff ! (plus
 > it's a waste of energy storing 12V, converting back to 240V,
 > only to drop it back to 12V and 5V in the psu.. It'd be more
 > sensible to run a 12V psu from a car battery, with a
 > trickle charger attached.. (unless there's a better way?) )
 >
 > Regards,
 > Chris<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

On Wed, 25 Aug 2004 12:20:48 GMT, "Skeleton Man"
<invalid.DeleteThis@guestwho.com> wrote:

 >Hi,
 >
 >I just got a new set of speakers (logitch z-340), and they seem very
 >sensitive to electrical noise (my old speakers weren't).
 >Every time the motor on my fridge cuts in or out (or someone turns a light
 >on or off), then I get a distorted clicking noise through the speakers. The
 >noise only lasts half a second, but it's annoying !
 >
 >Any suggestions on fixing this ?
 >
 >Regards,
 >Chris
 >


I suspect those have a rather basic, poorly filtered switching
power supply inside... is this correct, do they come with a power
brick or wall-wart supply or just an AC cord that plugs into the
subwoofer? It probably isn't even grounded. Granted it is
possible to have a subwoofer receiving power without it being a
switching supply inside, but it seems very uncommon, I've never
seen such done with computer speakers.

You might try any decent line filter. Open up the sub and see
how much room there is inside. If you aren't comfortable dealing
with AC power then buy a standalone "enclosure" that has a power
outlet on it (which may be the best overall solution since you
could plug other things into it as well) or you could install a
filter of maximum size possible in the subwoofer, in series with
the AC input (note that the AC jack may be surface-mounted on the
PCB so some creativity could be needed to break the circuit and
put the filter inline).<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

I'm not sure about 240V, but a good quality $40US surge protector will
filter noise and help stop surges. This kind of protection is included in
most of the $40US battery UPS's, so it's much more cost effective to buy the
UPS.

-Max


"Skeleton Man" <invalid.DeleteThis@guestwho.com> wrote in message
news:BQiXc.7923$D7.4041@news-server.bigpond.net.au...

 > I'm not inclinded to buy a UPS, as it's a coupla hundred bux just to keep
 > the PC up for a few mins to save stuff ! (plus it's a waste of energy
 > storing 12V, converting back to 240V, only to drop it back to 12V and 5V
 > in
 > the psu.. It'd be more sensible to run a 12V psu from a car battery, with
 > a
 > trickle charger attached.. (unless there's a better way?) )
 >
 > Regards,
 > Chris
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

On Fri, 27 Aug 2004 01:08:17 GMT, "Max" <maximus DeleteThis @portvista.com>
wrote:

 >I'm not sure about 240V, but a good quality $40US surge protector will
 >filter noise and help stop surges. This kind of protection is included in
 >most of the $40US battery UPS's, so it's much more cost effective to buy the
 >UPS.
 >
 >-Max

There is a trivial, if any, noise filtration circuit in a $40
UPS. For example I'm thinking of some from APC, 35-500VA range
should fall in a $40 range and certainly doesn't have a
sufficient filter.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

 >I suspect those have a rather basic, poorly filtered switching
 >power supply inside... is this correct, do they come with a power
 >brick or wall-wart supply or just an AC cord that plugs into the
 >subwoofer? It probably isn't even grounded. Granted it is
 >possible to have a subwoofer receiving power without it being a
 >switching supply inside, but it seems very uncommon, I've never
 >seen such done with computer speakers.

AC cord just goes into the subwoofer, and it's not grounded no.

 >You might try any decent line filter. Open up the sub and see
 >how much room there is inside.

Would one of those EMI filters from a switch mode psu work ? (I have several
dead power supplies which I could salvage one from)

If the AC input is PCB mounted I won't bother modifying it (too much work
for a minor problem), I'll just buy some kind of inline plug-in filter..

Regards,
Chris<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

An example with spec numbers and schematic was provided
previously. You will probably need to build a separate box on
the line cord to install proper filtering:
<a style='text-decoration: underline;' href="http://www.cor.com/catalog/filters/AQ/schematic.htm" target="_blank">http://www.cor.com/catalog/filters/AQ/schematic.htm</a>
<a style='text-decoration: underline;' href="http://www.cor.com/catalog/filters/AQ/Default.htm" target="_blank">http://www.cor.com/catalog/filters/AQ/Default.htm</a>

In the meantime, there is a trivial, if any, noise
filtration circuit in a $40 UPS. However that UPS could output
so much noise in battery backup mode to be a test bench for
filter contruction. Many UPSes actually output some of the
dirtiest, noisiest power when operating from battery. And
even that noise should not adversely affect a speaker power
supply. Borrow a UPS for testing to both learn how bad the
power supply is AND to help install sufficient noise filters.

Grounding should have nothing to do with this type of
noise. However saftey grounding the external filter box may
be required and may have some additional benefits. Three wire
AC cord to filter box. Then two wire cord to Subwoofer.

Skeleton Man wrote:
  >> I suspect those have a rather basic, poorly filtered switching
  >> power supply inside... is this correct, do they come with a power
  >> brick or wall-wart supply or just an AC cord that plugs into the
  >> subwoofer? It probably isn't even grounded. Granted it is
  >> possible to have a subwoofer receiving power without it being a
  >> switching supply inside, but it seems very uncommon, I've never
  >> seen such done with computer speakers.
 >
 > AC cord just goes into the subwoofer, and it's not grounded no.
 >
  >> You might try any decent line filter. Open up the sub and see
  >> how much room there is inside.
 >
 > Would one of those EMI filters from a switch mode psu work ? (I
 > have several dead power supplies which I could salvage one from)
 >
 > If the AC input is PCB mounted I won't bother modifying it (too
 > much work for a minor problem), I'll just buy some kind of
 > inline plug-in filter..
 >
 > Regards,
 > Chris<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances 

I would suggest looking into line filters, the ones you describe should be
able to be used (if you cant fit them internally, consider an external zippy
box and cutting the power cord).

As for all the US people suggesting to buy a "$30.00US" UPS, the situation
is a bit bleaker over here guys. On average for a cheap UPS we pay around
the $130.00 AUS (~$91.00US), but that has actual line filtering (I believe
it is one of the requirements over here).

Jim.

"Skeleton Man" <invalid RemoveThis @guestwho.com> wrote in message
news:B%EXc.9810$D7.1207@news-server.bigpond.net.au...
  > >I suspect those have a rather basic, poorly filtered switching
  > >power supply inside... is this correct, do they come with a power
  > >brick or wall-wart supply or just an AC cord that plugs into the
  > >subwoofer? It probably isn't even grounded. Granted it is
  > >possible to have a subwoofer receiving power without it being a
  > >switching supply inside, but it seems very uncommon, I've never
  > >seen such done with computer speakers.
 >
 > AC cord just goes into the subwoofer, and it's not grounded no.
 >
  > >You might try any decent line filter. Open up the sub and see
  > >how much room there is inside.
 >
 > Would one of those EMI filters from a switch mode psu work ? (I have
several
 > dead power supplies which I could salvage one from)
 >
 > If the AC input is PCB mounted I won't bother modifying it (too much work
 > for a minor problem), I'll just buy some kind of inline plug-in filter..
 >
 > Regards,
 > Chris
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: noise from other appliances