[Toby Newman]

I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533

--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[GregS[_3_]]

In article , Toby Newman wrote:
I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533


Fine, but are you sure its the amplifier.
What else is in the system.

I would first start out with a good surge strip like a Tripp-Lite that
has built in filters.

greg

[Eeyore]

Toby Newman wrote:

The first think I'll try is putting a surge protector between the amp
and the wall.

Entirely POINTLESS ! It won't do anything. You need a FILTER not a surge
protector.

As for blaming the amp, remind yourself that it wasn't designed to coexist
with a LAN over power cables.

Graham

[Eeyore]

Toby Newman wrote:

starting with the simple things like ferrite rings

Again, that would do almost nothing for low frequencies.

Graham

[GregS[_3_]]

In article , Toby Newman wrote:
I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533


You have to hook up the amp and speakers and disconnect
all amplifier inputs. Does it go away .??

greg

[Arny Krueger]

"Toby Newman" wrote in message


I've run my home LAN over mains using DLink's DHP-301
PowerLine HD Network Starter Kit in a bid to reduce
wires. I was very happy with
the new system until I turned on my Marantz 1050
amplifier yesterday
and found that, being a piece of hardware from the 70s,
it's picking
up the noise of the LAN. Sounds like rapid switching
between a 6kHz and 7kHz square wave.

There are other ways for noise to get into your system, besides the power
line.

It is quite possible taht a modern power amp or receiver would have the
identically same problem.

I guess the Marantz
designers didn't anticipate anything but 50Hz hum on the
power supply and didn't see fit to filter for anything
more than that.

Only a guess, and one that I would agree with the others - its a lower
probability.

The first think I'll try is putting a surge protector
between the amp and the wall.

Why? This isn't about surges, it is about EMI. Surges are defined as
relatively long-term (i.e. milliseconds) increases in the voltage at the
input to your amplifier. There's nothing inside your LAN that can produce
surges that big. I'd bet that 5 volts is the largest voltage anyplace inside
your LAN equipment, and in terms of a power line, that's a nit. The surges
that a surge protector works against are dozens or hundreds or even
thousands of volts.

The manufacturer says that these items must
not be used alongside the Powerline device because they
interfere with the network connection. I will try to use
this shortcoming to my favour.

I suspect that they are worried that a surge protector would make additional
interference.

If that fails, I'm planning to pop the case and add some
filtering inside, starting with the simple things like
ferrite rings and then moving up to adding capacitors or
a mains filter if that fails.

First thing I'd do is swap in a new cheap ($80) receiver - borrowed from a
friend or something. If it has the same problem, then look at the
possibility of interference pick up by the signal cables or other gear in
the system.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The power transformer in equipment like this is a major barrier to power
line noise. It's got great response at 50-60 Hz and lousy high frequency
response.

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533

Even the thought of this equipment is giving hams and other users of
RF-based equipment heart attacks. But its not about surges, its about RFI
and EMI.

If you want to filter out what your LAN is pumping into the power line, get
a power line filter, which may also have surge protection.

Here's some examples:

http://www.e-sonic.com/aboutus/cat/S...uppressors.pdf

anything that says it has effective line filtering built-in.

The reason why everything on the page has surge protectors is that surge
protection is cheap to add. Good line filtering can cost a little money.

[Toby Newman]

On 2008-01-28, GregS wrote:
In article , Toby Newman wrote:
I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533


Fine, but are you sure its the amplifier.
What else is in the system.

I would first start out with a good surge strip like a Tripp-Lite that
has built in filters.

The noise is there even when I remove any input devices, so the only items
in the system are two speakers and an amplifier.

--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[Trevor Wilson[_2_]]

"Toby Newman" wrote in message
...
I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

**Waste of time and money. The amp is picking up the noise. You need to
suppress it at the source.


If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

**Suppress the noise at the source. You could try shielded LAN cable.

Trevor Wilson

[Richard Crowley]

"Trevor Wilson" wrote ...
"Toby Newman" wrote ...
The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

**Waste of time and money.

Indeed. Most "surge protectors" are cheap plastic power strips
with a couple of 72-cent varistor transzorb devices in them.
They do nothing to filter power line noise.

The amp is picking up the noise.

Or maybe some other part of his audio chain is picking it up,
but since they are likely all powered from the mains, the
effect is the same.

You need to suppress it at the source.

The OP is intentionally generating (and using) the "interference".
Read on.

If that fails, I'm planning to pop the case and add some filtering
inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

**Suppress the noise at the source. You could try shielded LAN cable.

The point is that the OP isn't using LAN cable at all. He is using
one of those gadgets that run data over the power line. Surpressing
the "noise" at the source would mean turning off his power-line
network gadgets.

OTOH, he is likely much better off using one of the modern (and very
inexpensive) wireless networking products rather than the dated (and
aging) powerline solution.

[Trevor Wilson[_2_]]

"Richard Crowley" wrote in message
...
"Trevor Wilson" wrote ...
"Toby Newman" wrote ...
The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

**Waste of time and money.

Indeed. Most "surge protectors" are cheap plastic power strips
with a couple of 72-cent varistor transzorb devices in them.
They do nothing to filter power line noise.

**Even if they do, it won't work anyway. The 1050, like all 'modern' amps
has excellent PSSRR. If an LAN noise makes it through the power transformer
(which is unlikely), then the filter caps and regulated power supplies will
clean up whatever is left.


The amp is picking up the noise.

Or maybe some other part of his audio chain is picking it up,
but since they are likely all powered from the mains, the
effect is the same.

You need to suppress it at the source.

The OP is intentionally generating (and using) the "interference".
Read on.

If that fails, I'm planning to pop the case and add some filtering
inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

**Suppress the noise at the source. You could try shielded LAN cable.

The point is that the OP isn't using LAN cable at all. He is using
one of those gadgets that run data over the power line. Surpressing
the "noise" at the source would mean turning off his power-line
network gadgets.

**YIKES! You're right. I had no idea that anyone in their right mind would
use such a thing. Cables or wireless is the way.


OTOH, he is likely much better off using one of the modern (and very
inexpensive) wireless networking products rather than the dated (and
aging) powerline solution.

**Of course.

Trevor Wilson

[Kevin McMurtrie]

In article ,
Toby Newman wrote:

I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533

It's hard to figure a schematic from only the photo. My guess is that
there's an RF ground loop between the transformer and the speaker lines.
It might work to move the speaker commons or the transformer center tap
to a better point on the board.

If 6KHz is a secondary carrier of a much higher frequency, a simple RF
filter might work. Wrap the power cord around one of those large
rectangular chokes that snap together. That will block common-mode RF
without adding any series inductance to the input power. Don't separate
any wire pairs.

--
I don't read Google's spam. Reply with another service.

[Eisboch]

"Arny Krueger" wrote in message
. ..

The power transformer in equipment like this is a major barrier to power
line noise. It's got great response at 50-60 Hz and lousy high frequency
response.

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533


I was thinking that a small, 1:1 isolation transformer for the Marantz might
get rid of the LAN noise.

Eisboch

[Toby Newman]

On 2008-01-28, GregS wrote:
In article , Toby Newman wrote:
I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533

You have to hook up the amp and speakers and disconnect
all amplifier inputs. Does it go away .??

It remains when there are no devices attached to the inputs,
and irrespective of the position of the source select knob. The volume
knob doesn't affect the level of the noise, presumably because the noise
comes across the mains wire into the amplifier stage which is downstream
in the signal path from the volume control.

--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[Toby Newman]

On 2008-01-29, Richard Crowley wrote:
"Trevor Wilson" wrote ...
"Toby Newman" wrote ...
The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

**Waste of time and money.

Indeed. Most "surge protectors" are cheap plastic power strips
with a couple of 72-cent varistor transzorb devices in them.
They do nothing to filter power line noise.

The amp is picking up the noise.

Or maybe some other part of his audio chain is picking it up,
but since they are likely all powered from the mains, the
effect is the same.

You need to suppress it at the source.

The OP is intentionally generating (and using) the "interference".
Read on.

If that fails, I'm planning to pop the case and add some filtering
inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

**Suppress the noise at the source. You could try shielded LAN cable.

The point is that the OP isn't using LAN cable at all. He is using
one of those gadgets that run data over the power line. Surpressing
the "noise" at the source would mean turning off his power-line
network gadgets.

OTOH, he is likely much better off using one of the modern (and very
inexpensive) wireless networking products rather than the dated (and
aging) powerline solution.

I've switched from wireless to powerline for my LAN because of
unsatisfactory WiFi performance, but that is a topic for another
newsgroup.

--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[Toby Newman]

On 2008-01-28, Eeyore wrote:
Toby Newman wrote:
starting with the simple things like ferrite rings
Again, that would do almost nothing for low frequencies.
Graham

I don't know what's happening in the amplifier but it doesn't seem unfeasable
that a high-frequency noise on the mains (the LAN signal is up around 20-30MHz)
is causing audible subharmonics (~6KHz) in the amplifier. Filtering the MHz-range
signal with a ferrite ring before it reaches the amp would stop the subharmonics
being generated in the amplifier circuitry.

--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[Toby Newman]

On 2008-01-28, Eeyore wrote:


Toby Newman wrote:

The first think I'll try is putting a surge protector between the amp
and the wall.

Entirely POINTLESS ! It won't do anything. You need a FILTER not a surge
protector.

As for blaming the amp, remind yourself that it wasn't designed to coexist
with a LAN over power cables.

No need to shout. Surge protectors commonly include filtering and are much
more prolific than mains filters - I own several. I put one in-line with the
power supply to the amp last night and noted an attenuation of the noise
by around 50%. From this I learnt that filtering more agressively on the
mains supply to the amplifier could push the noise down into insignificance.

Until I'd done that test I didn't know if the interference was main-cable-borne
or airborne. I imagine my unshielded mains circuit is acting like a large
broadcat antenna with this LAN signal over it.

--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[Toby Newman]

On 2008-01-28, Arny Krueger wrote:
"Toby Newman" wrote in message


I've run my home LAN over mains using DLink's DHP-301
PowerLine HD Network Starter Kit in a bid to reduce
wires. I was very happy with
the new system until I turned on my Marantz 1050
amplifier yesterday
and found that, being a piece of hardware from the 70s,
it's picking
up the noise of the LAN. Sounds like rapid switching
between a 6kHz and 7kHz square wave.

There are other ways for noise to get into your system, besides the power
line.

It is quite possible taht a modern power amp or receiver would have the
identically same problem.

I guess the Marantz
designers didn't anticipate anything but 50Hz hum on the
power supply and didn't see fit to filter for anything
more than that.

Only a guess, and one that I would agree with the others - its a lower
probability.

The first think I'll try is putting a surge protector
between the amp and the wall.

Why? This isn't about surges, it is about EMI. Surges are defined as
relatively long-term (i.e. milliseconds) increases in the voltage at the
input to your amplifier. There's nothing inside your LAN that can produce
surges that big. I'd bet that 5 volts is the largest voltage anyplace inside
your LAN equipment, and in terms of a power line, that's a nit. The surges
that a surge protector works against are dozens or hundreds or even
thousands of volts.

The reason I will try a surge protector first is because consumer surge
protectors also often contain filtering, and are more readily available than
a mains filter. This will enable me to verify if the noise is borne on the mains
cable rather than carried through the air. If I see an attenuation I'll know that
the mains cable is the culprit.

The manufacturer says that these items must
not be used alongside the Powerline device because they
interfere with the network connection. I will try to use
this shortcoming to my favour.

I suspect that they are worried that a surge protector would make additional
interference.

If that fails, I'm planning to pop the case and add some
filtering inside, starting with the simple things like
ferrite rings and then moving up to adding capacitors or
a mains filter if that fails.

First thing I'd do is swap in a new cheap ($80) receiver - borrowed from a
friend or something. If it has the same problem, then look at the
possibility of interference pick up by the signal cables or other gear in
the system.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The power transformer in equipment like this is a major barrier to power
line noise. It's got great response at 50-60 Hz and lousy high frequency
response.

That's interesting to know.

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533

Even the thought of this equipment is giving hams and other users of
RF-based equipment heart attacks. But its not about surges, its about RFI
and EMI.

If you want to filter out what your LAN is pumping into the power line, get
a power line filter, which may also have surge protection.

Here's some examples:

http://www.e-sonic.com/aboutus/cat/S...uppressors.pdf

anything that says it has effective line filtering built-in.

The reason why everything on the page has surge protectors is that surge
protection is cheap to add. Good line filtering can cost a little money.


--
-Toby
Add the word afiduluminag to the subject to circumvent my email filters.

[GregS[_3_]]

In article , "Richard Crowley" wrote:
"Trevor Wilson" wrote ...
"Toby Newman" wrote ...
The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

**Waste of time and money.

Indeed. Most "surge protectors" are cheap plastic power strips
with a couple of 72-cent varistor transzorb devices in them.
They do nothing to filter power line noise.

There is capacitance in them. They have some effect.

greg

[GregS[_3_]]

In article , Toby Newman wrote:
On 2008-01-28, GregS wrote:
In article , Toby Newman
wrote:
I've run my home LAN over mains using DLink's DHP-301 PowerLine HD
Network Starter Kit in a bid to reduce wires. I was very happy with
the new system until I turned on my Marantz 1050 amplifier yesterday
and found that, being a piece of hardware from the 70s, it's picking
up the noise of the LAN. Sounds like rapid switching between a 6kHz and
7kHz square wave. I guess the Marantz designers didn't anticipate anything
but 50Hz hum on the power supply and didn't see fit to filter for anything
more than that.

The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

If that fails, I'm planning to pop the case and add some filtering inside,
starting with the simple things like ferrite rings and then moving up to
adding capacitors or a mains filter if that fails.

Before I start I'd be interested to hear your thoughts and opinions.

Links:
The Marantz 1050 (showing internals)
http://www.classic-audio.com/marantz/1050.html

The LAN-over-mains equipment:
http://www.dlink.com/products/?sec=1&pid=533

You have to hook up the amp and speakers and disconnect
all amplifier inputs. Does it go away .??

It remains when there are no devices attached to the inputs,
and irrespective of the position of the source select knob. The volume
knob doesn't affect the level of the noise, presumably because the noise
comes across the mains wire into the amplifier stage which is downstream
in the signal path from the volume control.


How about pulling the plug. If the protection circuits don't actuate right away
most amps will continue to play for some time. if the noise goes away then
you know its associated with the line.
Sometimes you have to filter the speaker lines if they are picking up the signal.
This usually happens with local AM stations. A cap and resistor across the outputs is standard practice.

greg

[GregS[_3_]]

In article , Toby Newman wrote:
On 2008-01-28, Arny Krueger wrote:
"Toby Newman" wrote in message


I've run my home LAN over mains using DLink's DHP-301
PowerLine HD Network Starter Kit in a bid to reduce
wires. I was very happy with
the new system until I turned on my Marantz 1050
amplifier yesterday
and found that, being a piece of hardware from the 70s,
it's picking
up the noise of the LAN. Sounds like rapid switching
between a 6kHz and 7kHz square wave.

There are other ways for noise to get into your system, besides the power
line.

It is quite possible taht a modern power amp or receiver would have the
identically same problem.

I guess the Marantz
designers didn't anticipate anything but 50Hz hum on the
power supply and didn't see fit to filter for anything
more than that.

Only a guess, and one that I would agree with the others - its a lower
probability.

The first think I'll try is putting a surge protector
between the amp and the wall.

Why? This isn't about surges, it is about EMI. Surges are defined as
relatively long-term (i.e. milliseconds) increases in the voltage at the
input to your amplifier. There's nothing inside your LAN that can produce
surges that big. I'd bet that 5 volts is the largest voltage anyplace inside
your LAN equipment, and in terms of a power line, that's a nit. The surges
that a surge protector works against are dozens or hundreds or even
thousands of volts.

The reason I will try a surge protector first is because consumer surge
protectors also often contain filtering, and are more readily available than
a mains filter. This will enable me to verify if the noise is borne on the
mains
cable rather than carried through the air. If I see an attenuation I'll know
that
the mains cable is the culprit.

Most places like The Home Depot or Radio Shack will have supressors with RFI filtering, just get one.

greg

[AZ Nomad]

On Wed, 30 Jan 2008 13:24:36 GMT, GregS wrote:
thousands of volts.

The reason I will try a surge protector first is because consumer surge
protectors also often contain filtering, and are more readily available than
a mains filter. This will enable me to verify if the noise is borne on the
mains
cable rather than carried through the air. If I see an attenuation I'll know
that
the mains cable is the culprit.


Most places like The Home Depot or Radio Shack will have supressors with
RFI filtering, just get one.

Neither HD or RS sell any power strips with RFI filtering. All they have is
cheap crap that use only transorbs. Nothing the sell is as good as a $5
single plug surge protector with a $5 outlet strip plugged in it. If you pay
more than $10, you're just ****ing your money away.

If you want RFI filtering, tripp-lite makes some great multibank filtered
outlet boxes. For example:
http://www.tripplite.com/shared/PDF/...lspec_3613.pdf

[GregS[_3_]]

In article , AZ Nomad wrote:
On Wed, 30 Jan 2008 13:24:36 GMT, GregS wrote:
thousands of volts.

The reason I will try a surge protector first is because consumer surge
protectors also often contain filtering, and are more readily available than
a mains filter. This will enable me to verify if the noise is borne on the
mains
cable rather than carried through the air. If I see an attenuation I'll know
that
the mains cable is the culprit.


Most places like The Home Depot or Radio Shack will have supressors with
RFI filtering, just get one.

Neither HD or RS sell any power strips with RFI filtering. All they have is
cheap crap that use only transorbs. Nothing the sell is as good as a $5
single plug surge protector with a $5 outlet strip plugged in it. If you pay
more than $10, you're just ****ing your money away.

If you want RFI filtering, tripp-lite makes some great multibank filtered
outlet boxes. For example:
http://www.tripplite.com/shared/PDF/...lspec_3613.pdf

The Home Depot has a bunch in the store. I would put some money up
that they do. Radio Shack has a a bunch on the web site.

You will see my first follow-up suggested Tripp-Lite, as I have
used them for many years.

Radio Shack also lists a Tripp-Lite isolation transformer.
The transformer has one leg tied to ground forming a new neutral.

If you buy a Tripp-Lite ISOBLOK2-0 for about $30, more outlets can be installed
after this, allthough is sometime best to proted one piece of equipment from another
on the SAME strip like the ISOBAR8ULTRA

greg

[Kevin McMurtrie]

In article ,
(GregS) wrote:

In article , "Richard Crowley"
wrote:
"Trevor Wilson" wrote ...
"Toby Newman" wrote ...
The first think I'll try is putting a surge protector between the amp
and the wall. The manufacturer says that these items must not be used
alongside the Powerline device because they interfere with the network
connection. I will try to use this shortcoming to my favour.

**Waste of time and money.

Indeed. Most "surge protectors" are cheap plastic power strips
with a couple of 72-cent varistor transzorb devices in them.
They do nothing to filter power line noise.

There is capacitance in them. They have some effect.

greg

1 to 4 nF, and it probably varies with the voltage.

--
I don't read Google's spam. Reply with another service.

[Richard Crowley]

"GregS" wrote ...
AZ Nomad wrote:
Neither HD or RS sell any power strips with RFI filtering. All they
have is
cheap crap that use only transorbs. Nothing the sell is as good as a
$5
single plug surge protector with a $5 outlet strip plugged in it. If
you pay
more than $10, you're just ****ing your money away.

The Home Depot has a bunch in the store. I would put some money up
that they do. Radio Shack has a a bunch on the web site.

Note that we are distinguishing between what the marketing
gerbs wrote on the bubble-pack card and the reality of what
is actually functional inside the gadget. You won't find REAL
RF filtering in a plastic consumer toy from RS or HD.