Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky

SparkyGuy wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...


Nope, only in higher-end legacy lab equipment. With legacy I mean 25
years old.

--
Regards, Joerg

http://www.analogconsultants.com

In article .net,
SparkyGuy writes:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Wrapped around old oscilloscope tubes.
I don't think old TVs ever merited its use.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Wed, 11 Apr 2007 19:50:17 GMT, SparkyGuy
wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky

Old oscilloscopes or the like would be your best bet for this

Barry

(Andrew Gabriel) wrote in
:

In article .net,
SparkyGuy writes:
Is this stuff prolific in old CRT monitors, or TVs? Need about a
square foot or so...

Wrapped around old oscilloscope tubes.
I don't think old TVs ever merited its use.


TV's used electroMAGNETIC deflection,which overwhelms Earth's field.
Those big,short TV CRTs just are not as sensitive as a long,narrow
electrostatic deflection scope CRT.

--
Jim Yanik
jyanik
at
kua.net

MassiveProng wrote in
:

On Thu, 12 Apr 2007 00:29:38 GMT, Joerg
Gave us:

Phil Allison wrote:

"Joerg"

SparkyGuy wrote:


Is this stuff prolific in old CRT monitors, or TVs? Need about a
square foot or so...


Nope, only in higher-end legacy lab equipment. With legacy I mean
25 years old.



** Where does this jerk off get his weird ideas from ??

The laws of magnetics have not been repealed in the last 25 years.

ALL good quality scopes using CRTs have mu-metal shields.

Even ones made today.


On flat screen displays? What for? Sorry, but that would be like
applying sun screen under the swimsuit.

Learn to read, dummy. It says RIGHT THERE 8 lines up... C R T s

**** off.

Note that he wrote he needs a square foot. I've only seen that much in
really old scopes.

Old 20" CRTs for PCs as well as some TVs have it.

Newer CRT versions have a skinny shield right around
the CRT and that ain't going to be enough to harvest a complete sqft
from.

Then he'll just have to cannibalize two. D'oh!

You got that lawyer yet?



--
Posted via a free Usenet account from http://www.teranews.com

SparkyGuy wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot or so...

Sparky

I have vague memories of hearing that if you bend it (or straighten it) then
it loses its special properties and needs to be re-annealed in some fancy
vacuum furnace thing or something like that. If you found a weird-shaped
piece of this stuff inside an old oscilloscope then I I'm not sure that you
could use it unless you needed it in exactly the shape that you found it
in.

There is a German place that sells little mu-metal boxes (cylindrical cans
actually):
http://www.buerklin.com/gruppen/KapH/H161260.asp
and here is some self-adhesive mu-metal foil:
http://www.buerklin.com/gruppen/KapL/L210600.asp

Actually I suppose the existence of the mu-metal foil product brings into
question whether it really matters whether you bend the mu-metal. Perhaps
someone else knows for certain.

Chris

SparkyGuy wrote:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky


Look at old oscilloscopes.

Bill K7NOM

"Joerg"
SparkyGuy wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot or so...


Nope, only in higher-end legacy lab equipment. With legacy I mean 25
years old.


** Where does this jerk off get his weird ideas from ??

The laws of magnetics have not been repealed in the last 25 years.

ALL good quality scopes using CRTs have mu-metal shields.

Even ones made today.




......... Phil

Phil Allison wrote:

"Joerg"

SparkyGuy wrote:


Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot or so...


Nope, only in higher-end legacy lab equipment. With legacy I mean 25
years old.



** Where does this jerk off get his weird ideas from ??

The laws of magnetics have not been repealed in the last 25 years.

ALL good quality scopes using CRTs have mu-metal shields.

Even ones made today.


On flat screen displays? What for? Sorry, but that would be like
applying sun screen under the swimsuit.

Note that he wrote he needs a square foot. I've only seen that much in
really old scopes. Newer CRT versions have a skinny shield right around
the CRT and that ain't going to be enough to harvest a complete sqft from.

--
Regards, Joerg

http://www.analogconsultants.com

"Andrew Gabriel" wrote in message
...
In article .net,
SparkyGuy writes:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot
or so...

Wrapped around old oscilloscope tubes.
I don't think old TVs ever merited its use.


Back in the days of 90 degree delta-gun shadowmask tubes, an external
magnetic shield most certainly was used around the bowl. The degaussing
coils were usually fixed to it, and it mounted using the same four corner
bolts as fixed the tube to the cabinet front. Many were my sliced fingers,
from the razor-sharp edges of these shields, when I was an apprentice
engaged in replacing these tubes ...

Arfa

"Joerg"
SparkyGuy wrote:
Phil Allison


Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot or so...


Nope, only in higher-end legacy lab equipment. With legacy I mean 25
years old.



** Where does this jerk off get his weird ideas from ??

The laws of magnetics have not been repealed in the last 25 years.

ALL good quality scopes using CRTs have mu-metal shields.

Even ones made today.


On flat screen displays?


** I said **CRT ** - you ****ING IDIOT !!!!

Try learning to read sometime !!!



Note that he wrote he needs a square foot. I've only seen that much in
really old scopes. Newer CRT versions have a skinny shield right around
the CRT and that ain't going to be enough to harvest a complete sqft from.


** Cheap Asian made scopes usually have no mu-metal at all, just a tin plate
ES shield around the neck - so they are highly subject to external AC
fields.

More expensive Asian scopes ( ie 60 MHz and up) usually have a mu-metal
shield on the CRT.

Examine almost any European, US or Australian made scope and you will find
it has a full size mu-metal shield -excepting scopes employing PDA (Post
Deflection Acceleration) where the mag shielding is not needed near the tube
face.




........ Phil

On Thu, 12 Apr 2007 00:29:38 GMT, Joerg
Gave us:

Phil Allison wrote:

"Joerg"

SparkyGuy wrote:


Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot or so...


Nope, only in higher-end legacy lab equipment. With legacy I mean 25
years old.



** Where does this jerk off get his weird ideas from ??

The laws of magnetics have not been repealed in the last 25 years.

ALL good quality scopes using CRTs have mu-metal shields.

Even ones made today.


On flat screen displays? What for? Sorry, but that would be like
applying sun screen under the swimsuit.

Learn to read, dummy. It says RIGHT THERE 8 lines up... C R T s

Note that he wrote he needs a square foot. I've only seen that much in
really old scopes.

Old 20" CRTs for PCs as well as some TVs have it.

Newer CRT versions have a skinny shield right around
the CRT and that ain't going to be enough to harvest a complete sqft from.

Then he'll just have to cannibalize two. D'oh!

On Wed, 11 Apr 2007 19:50:17 +0000, SparkyGuy wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...


I was looking for some mu metal one day, and someone suggested CoNetic:

http://www.magnetic-shield.com/produ...etic-size.html

Hope This Helps!
Rich

On Apr 11, 8:12 pm, Rich Grise wrote:
On Wed, 11 Apr 2007 19:50:17 +0000, SparkyGuy wrote:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

I was looking for some mu metal one day, and someone suggested CoNetic:

http://www.magnetic-shield.com/produ...etic-size.html

Hope This Helps!
Rich


Hmm. Its on topic and probably useful. Even addresses the annealing
question. Are you new to SED?

" wrote:

On Apr 11, 8:12 pm, Rich Grise wrote:
On Wed, 11 Apr 2007 19:50:17 +0000, SparkyGuy wrote:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

I was looking for some mu metal one day, and someone suggested CoNetic:

http://www.magnetic-shield.com/produ...etic-size.html

Hope This Helps!
Rich

Hmm. Its on topic and probably useful. Even addresses the annealing
question. Are you new to SED?


No, he just can't figure out which of 20 names to use.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

On Wed, 11 Apr 2007 19:50:17 GMT, SparkyGuy
wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky

Why?

John

You might try your local recycling center to see where thay tear down
old CRT monitors and TV's. Maybe if they let you come by you can spot some.

SparkyGuy wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky




--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

Isn't moo metal what they make cow magnets from!

SparkyGuy wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky




--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

I used to think so, but when I went to college, I learned that it's made
from cats!

Tim

--
"Librarians are hiding something." - Steven Colbert
Website @ http://webpages.charter.net/dawill/tmoranwms

"**THE-RFI-EMI-GUY**" wrote in message
...
Isn't moo metal what they make cow magnets from!

On Wed, 11 Apr 2007 20:20:12 -0700, John Larkin
Gave us:

On Wed, 11 Apr 2007 19:50:17 GMT, SparkyGuy
wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky

Why?


He wants to see if it works as well as tin foil for alien/government
shield hat making.

"MassiveProng" wrote in
message ...
On Wed, 11 Apr 2007 20:20:12 -0700, John Larkin
Gave us:

On Wed, 11 Apr 2007 19:50:17 GMT, SparkyGuy
wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a square
foot
or so...

Sparky

Why?


He wants to see if it works as well as tin foil for alien/government
shield hat making.

Wasn't there some of this stuff involved in a Lil' Abner episode?

"Arfa Daily" wrote in
:


"Andrew Gabriel" wrote in message
...
In article .net,
SparkyGuy writes:
Is this stuff prolific in old CRT monitors, or TVs? Need about a
square foot
or so...

Wrapped around old oscilloscope tubes.
I don't think old TVs ever merited its use.


Back in the days of 90 degree delta-gun shadowmask tubes, an external
magnetic shield most certainly was used around the bowl. The
degaussing coils were usually fixed to it, and it mounted using the
same four corner bolts as fixed the tube to the cabinet front. Many
were my sliced fingers, from the razor-sharp edges of these shields,
when I was an apprentice engaged in replacing these tubes ...

Arfa






Ah,yes,I remember TEK 650 series monitors having a metal CRT shield.



--
Jim Yanik
jyanik
at
kua.net

"Long Ranger" wrote in
thlink.net:


"MassiveProng" wrote in
message ...
On Wed, 11 Apr 2007 20:20:12 -0700, John Larkin
Gave us:

On Wed, 11 Apr 2007 19:50:17 GMT, SparkyGuy
wrote:

Is this stuff prolific in old CRT monitors, or TVs? Need about a
square foot
or so...

Sparky

Why?


He wants to see if it works as well as tin foil for alien/government
shield hat making.

Wasn't there some of this stuff involved in a Lil' Abner episode?




that was SCMOO-metal.

--
Jim Yanik
jyanik
at
kua.net

Why?

My bench power supply's transformer is coupling hum into my breadboard. Yes,
I can move my circuit farther away, but I'd rather solve the problem (short
of replacing an otherwise good supply) than the symptom.

It's a 70's vintage lam transformer with half a dozen secondary windings. I'd
prefer a toroid, but it will be cheaper to simply shield this one.
--
Sparky

On Thu, 12 Apr 2007 16:08:23 GMT, SparkyGuy
wrote:

Why?

My bench power supply's transformer is coupling hum into my breadboard. Yes,
I can move my circuit farther away, but I'd rather solve the problem (short
of replacing an otherwise good supply) than the symptom.

It's a 70's vintage lam transformer with half a dozen secondary windings. I'd
prefer a toroid, but it will be cheaper to simply shield this one.

Mu-metal probably won't help. A copper shorting strap around the
transformer would. You can make that out of sheet copper, or even bare
wire and a lot of solder.

Or, um, move it farther away.

John

John Larkin wrote:

On Thu, 12 Apr 2007 16:08:23 GMT, SparkyGuy
wrote:


Why?

My bench power supply's transformer is coupling hum into my breadboard. Yes,
I can move my circuit farther away, but I'd rather solve the problem (short
of replacing an otherwise good supply) than the symptom.

It's a 70's vintage lam transformer with half a dozen secondary windings. I'd
prefer a toroid, but it will be cheaper to simply shield this one.


Mu-metal probably won't help. A copper shorting strap around the
transformer would. You can make that out of sheet copper, or even bare
wire and a lot of solder.

Or, um, move it farther away.


Flashing material can be obtained at almost every major hardware store.
But not the Al stuff, as that won't solder...

--
Regards, Joerg

http://www.analogconsultants.com

Mu-metal probably won't help.

My understanding is that it should be high-nickel content metal, such as is
mu, and that without that content magnetic fields aren't much effected by
metals.

A copper shorting strap around the
transformer would. You can make that out of sheet copper, or even bare
wire and a lot of solder.

Or does solder serve as the poor-man's nickel?

Sounds like DIY mu-copper :-) You say "strap" which I interpret as not
full-height of the transformer. Should it be less-than the height of the
lams? Or is taller better?

Isn't that a lot of wire (a tertiary winding)?

Wrap the sheet around and bolt it under the feet of the xfmr? (Only need to
shield in 1 direction, really: forward.)

Or, um, move it farther away.

Yeah, thanks for that, John... :-)
--
Sparky

Flashing material can be obtained at almost every major hardware store.
But not the Al stuff, as that won't solder...

Can use Al if I don't need to solder? Or is it solder that makes it effective
against the magnetic field?

Thanks,
--
Sparky

On Thu, 12 Apr 2007 02:29:41 +0000, Michael A. Terrell wrote:
" wrote:
On Apr 11, 8:12 pm, Rich Grise wrote:
On Wed, 11 Apr 2007 19:50:17 +0000, SparkyGuy wrote:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

I was looking for some mu metal one day, and someone suggested CoNetic:

http://www.magnetic-shield.com/produ...etic-size.html

Hmm. Its on topic and probably useful. Even addresses the annealing
question. Are you new to SED?

No, he just can't figure out which of 20 names to use.

Hey, Michael - just because _you_ can't figure out which name I'm using,
doesn't mean that _I_ can't. ;-)

I use the different names to distinguish between whether I'm being
technical or goofing around.

Some people don't afford such simple considerations. :-)

Thanks!
Rich

SparkyGuy wrote:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...

Sparky

As soon as you cut it or otherwise stress it, mu metal becomes worthless.


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email:

Please visit my GURU's LAIR web site at http://www.tinaja.com

SparkyGuy wrote:

Flashing material can be obtained at almost every major hardware store.
But not the Al stuff, as that won't solder...


Can use Al if I don't need to solder? Or is it solder that makes it effective
against the magnetic field?


Al won't be very good but to be of some help against EM fields it would
at least need to be riveted. After a while it'll oxydize though.

Think of it this way: In order to muffle a magnetic field coming from
the inside you need to short out any induced currents. A work of caution
if you ever do that around toroid transformers: If there is a metallic
stud that holds them in place never, never let a shield touch that. It
might result in molten metal sparkling all around you.

--
Regards, Joerg

http://www.analogconsultants.com

On Thu, 12 Apr 2007 17:49:49 +0000, SparkyGuy wrote:
Mu-metal probably won't help.

My understanding is that it should be high-nickel content metal, such as is
mu, and that without that content magnetic fields aren't much effected by
metals.

A copper shorting strap around the
transformer would. You can make that out of sheet copper, or even bare
wire and a lot of solder.

Or does solder serve as the poor-man's nickel?

Sounds like DIY mu-copper :-) You say "strap" which I interpret as not
full-height of the transformer. Should it be less-than the height of the
lams? Or is taller better?

It goes right on the outside of the lams, and around the windings, in
the same direction as the windings, like this:
http://www.germes-online.com/direct/...ransformer.jpg

It acts as a shorted turn; it has something to do with "leakage inductance".

Cheers!
Rich

Rich Grise wrote:

On Thu, 12 Apr 2007 17:49:49 +0000, SparkyGuy wrote:

Mu-metal probably won't help.

My understanding is that it should be high-nickel content metal, such as is
mu, and that without that content magnetic fields aren't much effected by
metals.


A copper shorting strap around the
transformer would. You can make that out of sheet copper, or even bare
wire and a lot of solder.

Or does solder serve as the poor-man's nickel?

Sounds like DIY mu-copper :-) You say "strap" which I interpret as not
full-height of the transformer. Should it be less-than the height of the
lams? Or is taller better?


It goes right on the outside of the lams, and around the windings, in
the same direction as the windings, like this:
http://www.germes-online.com/direct/...ransformer.jpg

It acts as a shorted turn; it has something to do with "leakage inductance".


Yep, that's it. Just dawned on me where to buy the sheet stock: Hobby
shops or arts and crafts suppliers. The ones that cater to artists who
build stuff like Tiffany lamps or do other stained glass work. That's
where you can also buy copper tape, brass sheets and all that.

--
Regards, Joerg

http://www.analogconsultants.com

It goes right on the outside of the lams, and around the windings, in
the same direction as the windings, like this:

http://www.germes-
online.com/direct/dbimage/50068769/Power_Supply_Transformer.
jpg

Not necessary to ground it?

Is wider (as wide as the windings) best? Dimension confusion...

Thanks,
--
Sparky

On Thu, 12 Apr 2007 11:04:17 -0700, Don Lancaster
wrote:

SparkyGuy wrote:
Is this stuff prolific in old CRT monitors, or TVs? Need about a square foot
or so...


High MU metal is not a particularly rare material. I assume you are
attempting to shield something from a low frequency magnetic field.
You may find the cast-iron door of an old stove or wood furnace will
be all you need.

"Rich Grise" wrote in message
news
On Thu, 12 Apr 2007 17:49:49 +0000, SparkyGuy wrote:
Mu-metal probably won't help.

My understanding is that it should be high-nickel content metal, such as
is
mu, and that without that content magnetic fields aren't much effected by
metals.

A copper shorting strap around the
transformer would. You can make that out of sheet copper, or even bare
wire and a lot of solder.

Or does solder serve as the poor-man's nickel?

Sounds like DIY mu-copper :-) You say "strap" which I interpret as not
full-height of the transformer. Should it be less-than the height of the
lams? Or is taller better?

It goes right on the outside of the lams, and around the windings, in
the same direction as the windings, like this:
http://www.germes-online.com/direct/...ransformer.jpg

It acts as a shorted turn; it has something to do with "leakage
inductance".

Cheers!
Rich


That transformer in the picture is a ferrite cored one from a switch-mode
power supply, and is designed to run at a frequency of around 100kHz. A
copper band around such a tranny, is a whole different kettle of fish to
putting one around a low frequency power transformer. Some such trannies
have a copper shield right around the windings, inside the lamination limbs,
but if I recall correctly, this is more for electrostatic shielding
purposes, than magnetic. The first thing I would try, before getting all
complicated with mumetal shields, is to rotate the tranny through 90 degrees
in the horizontal, and if that doesn't work, doing the same in the vertical,
or any combination. I've found that this will often reduce or even eliminate
stray field pickup by adjacent circuitry. The tranny mounting holes may even
still line up in the best case, but even worst case, it's only a case of
drill 4 more, or make up a right-angle bracket.

Arfa

On Thu, 12 Apr 2007 19:33:09 GMT, SparkyGuy
wrote:

It goes right on the outside of the lams, and around the windings, in
the same direction as the windings, like this:

http://www.germes-
online.com/direct/dbimage/50068769/Power_Supply_Transformer.
jpg

Not necessary to ground it?

Not if your problem is magnetic field leakage.


Is wider (as wide as the windings) best? Dimension confusion...


Think of it as a single, shorted secondary turn but *outside* the
laminations. Any field that leaks out of the transformer induces a
current into the strap, and it in turn generates a field that fights
the excitation. It should be thick, wide, and well-shorted, which
means well soldered. Copper is best.

John

On Thu, 12 Apr 2007 16:08:23 GMT, SparkyGuy
Gave us:

Why?

My bench power supply's transformer is coupling hum into my breadboard. Yes,
I can move my circuit farther away, but I'd rather solve the problem (short
of replacing an otherwise good supply) than the symptom.

It's a 70's vintage lam transformer with half a dozen secondary windings. I'd
prefer a toroid, but it will be cheaper to simply shield this one.

Make sure you simply twist your output lines from the banana jacks,
right up to the circuit under test. Your noise figure should drop a
lot on that act alone. A couple turns per inch... not too damn loose
or it does no good.

On Thu, 12 Apr 2007 17:50:43 GMT, Rich Grise Gave
us:

Hey, Michael - just because _you_ can't figure out which name I'm using,
doesn't mean that _I_ can't. ;-)

Bool****. Have another drink, you alcoholic retard.

I use the different names to distinguish between whether I'm being
technical or goofing around.

More bool****. You use them because secretly you want us all to know
just how retarded you really are.

Some people don't afford such simple considerations. :-)

You're an idiot.