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Rayner Lucas January 12th 21 09:48 PM

Reviewing a cheap CRT degaussing wand
 
Hi all. This post is a review of the cheap "green stick" CRT degaussing
wands, as I haven't found much discussion of them and some other
repairers of vintage monitors may find it useful.

CRT degaussing tools seem to be hard to find these days. Occasional used
ones come up for sale, and there are still some to be found in the US.
However, in the UK they're near-unobtainable. The main source seems to
be eBay sellers in China, all of whom are selling the same type: a wand-
style degausser in a green plastic shell. So, having a couple of CRTs
with purity problems, I bought one to see if it would do any good.

The wand cost about 15 GBP and arrived within a couple of weeks. There
was no documentation included, leaving me with just the specs given in
the eBay listing, which read:
-Relative magnetic field: 70MT
-Load current: 1A
-Working hours: 20 seconds
-Power: 220V
-Specifications: About 31*31*200(mm)

The outer shell is some soft semi-translucent plastic (polythene?), and
feels extremely cheap. A momentary switch pokes out of the top of the
casing (a momentary switch is good, as it stops me accidentally leaving
the coil energised).

The wand came with a moulded two-prong plug, which I had to cut off to
fit a UK plug. And... I have never seen mains cable that thin before. It
is, at least, double insulated, but the conductors are at most 28AWG and
possibly even thinner (it's hard to measure stranded cable, but the
diameter is somewhere around 0.25mm to 0.35mm). The strain relief clamp
in the UK plug wouldn't even hold the cable until I wrapped some extra
plastic around it. Oof. Looking at the ampacity ratings on the Wikipedia
article for American Wire Gauge, that cable must be very close to, if
not exceeding, its recommended current rating. It feels worryingly
plausible that someone, somewhere made the calculation "it's fine, if
they push the button for too long the coil will burn out before the
cable insulation melts".

However, the tool does what it's supposed to and noticeably reduced the
blotches visible on the CRT display. I used the standard technique of
powering the coil from a couple of metres away, bringing it up to the
CRT face, circling it around a couple of times, then smoothly backing
away two or three metres before switching off again. I definitely
recommend sticking to the stated maximum of 20 seconds continuous
operation and letting the wand cool fully before using it again. The
heat seems to take a few seconds to conduct to the outside of the
casing, so it's not until after you've switched it off that you feel how
warm it's really getting.

I popped the end cap off the casing to take a look inside, but haven't
disassembled it further. Strain relief is just a knot in the mains
cable. I don't see any current limiting apart from the coil itself. The
coil is wrapped around a core of steel plates, and seems to have some
more plastic insulation around it. The non-business end of the coil
seems to have some copper mesh shielding. Hooking the whole thing up to
a component tester, coil resistance measures around 140 ohms, with an
inductance of 320mH.

In summary,

Pros:
- Cheap.
- Does what it's supposed to.

Cons:
- Not particularly sturdy.
- Probably not the safest thing ever, use with caution.

If there were better-quality tools available, I would definitely buy
those instead. But there weren't, and this one did at least provide the
functionality I needed.

HTH,
Rayner

--
Big-8 Management Board: https://www.big-8.org
Homepage: http://magic-cookie.co.uk

John Robertson January 12th 21 11:00 PM

Reviewing a cheap CRT degaussing wand
 
On 2021/01/12 12:48 p.m., Rayner Lucas wrote:
Hi all. This post is a review of the cheap "green stick" CRT degaussing
wands, as I haven't found much discussion of them and some other
repairers of vintage monitors may find it useful.

CRT degaussing tools seem to be hard to find these days. Occasional used

....

If there were better-quality tools available, I would definitely buy
those instead. But there weren't, and this one did at least provide the
functionality I needed.

HTH,
Rayner


I use a large Weller Soldering Gun when I can't find one of the
degaussing coils in the shop...

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

Ralph Mowery January 12th 21 11:27 PM

Reviewing a cheap CRT degaussing wand
 
In article ,
says...

I use a large Weller Soldering Gun when I can't find one of the
degaussing coils in the shop...




I also used the Weller or what ever Gun I had handy on the old CRTs.

Just about any coil of wire will work that does not draw too much
current.



Rayner Lucas January 13th 21 01:56 AM

Reviewing a cheap CRT degaussing wand
 
In article t,
says...

In article ,
says...

I use a large Weller Soldering Gun when I can't find one of the
degaussing coils in the shop...


I also used the Weller or what ever Gun I had handy on the old CRTs.

Just about any coil of wire will work that does not draw too much
current.


Oh, that's a neat idea, I never thought to try a heating coil. I did
consider making my own, but with no idea what spec to aim for, buying
one seemed like it had a better chance of success :-)

Rayner

--
Big-8 Management Board:
https://www.big-8.org
Homepage: http://magic-cookie.co.uk

Trevor Wilson[_4_] January 13th 21 02:48 AM

Reviewing a cheap CRT degaussing wand
 
On 13/01/2021 7:48 am, Rayner Lucas wrote:
Hi all. This post is a review of the cheap "green stick" CRT degaussing
wands, as I haven't found much discussion of them and some other
repairers of vintage monitors may find it useful.

CRT degaussing tools seem to be hard to find these days. Occasional used
ones come up for sale, and there are still some to be found in the US.
However, in the UK they're near-unobtainable. The main source seems to
be eBay sellers in China, all of whom are selling the same type: a wand-
style degausser in a green plastic shell. So, having a couple of CRTs
with purity problems, I bought one to see if it would do any good.

The wand cost about 15 GBP and arrived within a couple of weeks. There
was no documentation included, leaving me with just the specs given in
the eBay listing, which read:
-Relative magnetic field: 70MT
-Load current: 1A
-Working hours: 20 seconds
-Power: 220V
-Specifications: About 31*31*200(mm)

The outer shell is some soft semi-translucent plastic (polythene?), and
feels extremely cheap. A momentary switch pokes out of the top of the
casing (a momentary switch is good, as it stops me accidentally leaving
the coil energised).

The wand came with a moulded two-prong plug, which I had to cut off to
fit a UK plug. And... I have never seen mains cable that thin before. It
is, at least, double insulated, but the conductors are at most 28AWG and
possibly even thinner (it's hard to measure stranded cable, but the
diameter is somewhere around 0.25mm to 0.35mm). The strain relief clamp
in the UK plug wouldn't even hold the cable until I wrapped some extra
plastic around it. Oof. Looking at the ampacity ratings on the Wikipedia
article for American Wire Gauge, that cable must be very close to, if
not exceeding, its recommended current rating. It feels worryingly
plausible that someone, somewhere made the calculation "it's fine, if
they push the button for too long the coil will burn out before the
cable insulation melts".

However, the tool does what it's supposed to and noticeably reduced the
blotches visible on the CRT display. I used the standard technique of
powering the coil from a couple of metres away, bringing it up to the
CRT face, circling it around a couple of times, then smoothly backing
away two or three metres before switching off again. I definitely
recommend sticking to the stated maximum of 20 seconds continuous
operation and letting the wand cool fully before using it again. The
heat seems to take a few seconds to conduct to the outside of the
casing, so it's not until after you've switched it off that you feel how
warm it's really getting.

I popped the end cap off the casing to take a look inside, but haven't
disassembled it further. Strain relief is just a knot in the mains
cable. I don't see any current limiting apart from the coil itself. The
coil is wrapped around a core of steel plates, and seems to have some
more plastic insulation around it. The non-business end of the coil
seems to have some copper mesh shielding. Hooking the whole thing up to
a component tester, coil resistance measures around 140 ohms, with an
inductance of 320mH.

In summary,

Pros:
- Cheap.
- Does what it's supposed to.

Cons:
- Not particularly sturdy.
- Probably not the safest thing ever, use with caution.

If there were better-quality tools available, I would definitely buy
those instead. But there weren't, and this one did at least provide the
functionality I needed.

HTH,
Rayner


**I have always been an audio tech. I have always avoided TV work where
possible. However, back in the day, I would frequently perform a CRT
degauss, using my Han-D-Mag head demagnetiser. I found that it could
deal with any degaussing requirement.

https://www.ebay.com.au/itm/Tape-hea...-/271234117484

Geez, they're expensive nowadays. I still have mine.

--
Trevor Wilson
www.rageaudio.com.au

--
This email has been checked for viruses by Avast antivirus software.
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Phil Allison[_3_] January 13th 21 03:08 AM

Reviewing a cheap CRT degaussing wand
 
Trevor Wilson wrote:
================

**I have always been an audio tech. I have always avoided TV work where
possible. However, back in the day, I would frequently perform a CRT
degauss, using my Han-D-Mag head demagnetiser. I found that it could
deal with any degaussing requirement.

https://www.ebay.com.au/itm/Tape-hea...-/271234117484

Geez, they're expensive nowadays. I still have mine.


** I once acquired a demagnetiser that, far as I could tell, was incapable of demagnetising anything.
Had no effect on tape heads or the tiniest screwdrivers. It was the Teac E1 as listed in your link.

So acting on a hunch, I made a coil of enamel wire ( about 15 turns) just big enough to slip over the head concerned and energised it from a small 6.3V tranny. The coil would get quite hot in about 30 seconds.

While energised, I popped it over the head and slowly removed it far away.

Totally worked on even the most magnetised heads.

Necessity is .......


...... Phil


danny burstein January 13th 21 05:47 AM

Reviewing a cheap CRT degaussing wand
 
[snip]

Back, umm... 1977ish.. (*whew*) I took a
slotted steel wallmount bookcase rail
(about 1/4 by 1/2 inch by 4 feet), wrapped
some, umm, probably #18 lampcord around
it, and wired it to a 12VAC transformer.

I added in something like a 50 watt 120vac
lamp (lighbulb) in series as a current
limiter.

Yeah, I had no idea what I was doing.

Anyway, I then plugged this into a 120VAC
power strip, put on some safety gloves
and goggles, held it near the tv, and
had my friend turn on the power strip.

It worked!

1990ish I used a handheld Radio Shack brand
tape degausser for the same purpose. And
yes, it worked, too.

So these things are doable...



--
__________________________________________________ ___
Knowledge may be power, but communications is the key

[to foil spammers, my address has been double rot-13 encoded]

John Robertson January 13th 21 07:47 AM

Reviewing a cheap CRT degaussing wand
 
On 2021/01/12 4:56 p.m., Rayner Lucas wrote:
In article t,
says...

In article ,
says...

I use a large Weller Soldering Gun when I can't find one of the
degaussing coils in the shop...


I also used the Weller or what ever Gun I had handy on the old CRTs.

Just about any coil of wire will work that does not draw too much
current.


Oh, that's a neat idea, I never thought to try a heating coil. I did
consider making my own, but with no idea what spec to aim for, buying
one seemed like it had a better chance of success :-)

Rayner


You need something that puts out a large AC field - like the unshielded
transformer used in soldering guns.

An electric heating coil has a very small magnetic field, I'd say it was
most unlikely to be useful for degaussing...

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

John Robertson January 13th 21 07:50 AM

Reviewing a cheap CRT degaussing wand
 
On 2021/01/12 5:48 p.m., Trevor Wilson wrote:
On 13/01/2021 7:48 am, Rayner Lucas wrote:
Hi all. This post is a review of the cheap "green stick" CRT degaussing
wands, as I haven't found much discussion of them and some other
repairers of vintage monitors may find it useful.

CRT degaussing tools seem to be hard to find these days. Occasional used

....
In summary,

Pros:
- Cheap.
- Does what it's supposed to.

Cons:
- Not particularly sturdy.
- Probably not the safest thing ever, use with caution.

If there were better-quality tools available, I would definitely buy
those instead. But there weren't, and this one did at least provide the
functionality I needed.

HTH,
Rayner


**I have always been an audio tech. I have always avoided TV work where
possible. However, back in the day, I would frequently perform a CRT
degauss, using my Han-D-Mag head demagnetiser. I found that it could
deal with any degaussing requirement.

https://www.ebay.com.au/itm/Tape-hea...-/271234117484


Geez, they're expensive nowadays. I still have mine.


A bit cheaper on this side of the pond:

https://www.atrtape.com/products/han-d-mag

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

Rayner Lucas January 13th 21 09:05 AM

Reviewing a cheap CRT degaussing wand
 
In article ,
says...

You need something that puts out a large AC field - like the unshielded
transformer used in soldering guns.

An electric heating coil has a very small magnetic field, I'd say it was
most unlikely to be useful for degaussing...


Ah, thanks, I get it now! I don't have a soldering gun, but it would
certainly have been a lot easier to find one for sale than a degaussing
coil. Or I guess I could've looked around for something else with a
transformer I could salvage.

Rayner

--
Big-8 Management Board:
https://www.big-8.org
Homepage: http://magic-cookie.co.uk

Trevor Wilson[_4_] January 13th 21 09:20 AM

Reviewing a cheap CRT degaussing wand
 
On 13/01/2021 1:08 pm, Phil Allison wrote:
Trevor Wilson wrote:
================

**I have always been an audio tech. I have always avoided TV work where
possible. However, back in the day, I would frequently perform a CRT
degauss, using my Han-D-Mag head demagnetiser. I found that it could
deal with any degaussing requirement.

https://www.ebay.com.au/itm/Tape-hea...-/271234117484

Geez, they're expensive nowadays. I still have mine.


** I once acquired a demagnetiser that, far as I could tell, was incapable of demagnetising anything.
Had no effect on tape heads or the tiniest screwdrivers. It was the Teac E1 as listed in your link.

So acting on a hunch, I made a coil of enamel wire ( about 15 turns) just big enough to slip over the head concerned and energised it from a small 6.3V tranny. The coil would get quite hot in about 30 seconds.

While energised, I popped it over the head and slowly removed it far away.

Totally worked on even the most magnetised heads.

Necessity is .......


**My Han-D-Mag demagnetises everything. Heads, TV screens, screwdrivers,
etc. As for necessity, I had a Naka in the other day and my part time
employee told me that the Han-D-Mag was too big to reach the heads. I
dug out this crappy little demag I bought years ago. Didn't work.
Stripped it down, re-wound the coil with thicker wire and ran it off
12VAC. Works a treat.

BTW: I have this neat and VERY sensitive magnetometer used to test for
residual magnetism.

--
Trevor Wilson
www.rageaudio.com.au

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Trevor Wilson[_4_] January 13th 21 09:21 AM

Reviewing a cheap CRT degaussing wand
 
On 13/01/2021 5:50 pm, John Robertson wrote:
On 2021/01/12 5:48 p.m., Trevor Wilson wrote:
On 13/01/2021 7:48 am, Rayner Lucas wrote:
Hi all. This post is a review of the cheap "green stick" CRT degaussing
wands, as I haven't found much discussion of them and some other
repairers of vintage monitors may find it useful.

CRT degaussing tools seem to be hard to find these days. Occasional used

...
In summary,

Pros:
- Cheap.
- Does what it's supposed to.

Cons:
- Not particularly sturdy.
- Probably not the safest thing ever, use with caution.

If there were better-quality tools available, I would definitely buy
those instead. But there weren't, and this one did at least provide the
functionality I needed.

HTH,
Rayner


**I have always been an audio tech. I have always avoided TV work
where possible. However, back in the day, I would frequently perform a
CRT degauss, using my Han-D-Mag head demagnetiser. I found that it
could deal with any degaussing requirement.

https://www.ebay.com.au/itm/Tape-hea...-/271234117484


Geez, they're expensive nowadays. I still have mine.


A bit cheaper on this side of the pond:

https://www.atrtape.com/products/han-d-mag

John :-#)#


**That's more like it.

--
Trevor Wilson
www.rageaudio.com.au

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Phil Allison[_3_] January 13th 21 10:24 AM

Reviewing a cheap CRT degaussing wand
 
John Robertson wrote:
==================

I use a large Weller Soldering Gun when I can't find one of the
degaussing coils in the shop...

I also used the Weller or what ever Gun I had handy on the old CRTs.

Just about any coil of wire will work that does not draw too much
current.



You need something that puts out a large AC field - like the unshielded
transformer used in soldering guns.


** Utter nonsense.

Such trannies radiate SFA mag fileld.


An electric heating coil has a very small magnetic field,


** But that is *not* what a soldering gun loop is.

Single turn sure - but a carrying about 250 amps !!.

So, at close range the same as a 25 turn coil carrying 10 amps.

Much like the example I posted earlier that WORKED like a treat.



....... Phil




Peter W. January 13th 21 01:57 PM

Reviewing a cheap CRT degaussing wand
 
https://www.zoro.com/gc-electronics-...17/i/G2187702/

https://www.travers.com/portable-mag... Aqo7EALw_wcB

https://www.ebay.com/i/123990657206?...evt=1&mkcid=28

Guys and gals - these things are available OTC here in the US. Why not in the UK? Oh, but they a

https://www.bartington.com/degaussing-wand/

https://www.ebay.co.uk/itm/NEW-CRT-M...AOxyKsZRwen D

For a one-off use, I would likely stick to the soldering gun - does the trick, even if used "off-label". I bring my 100/300 watt Craftsman gun to Kutztown for the occasional chassis connection, and it is as often as not borrowed by the TV guys for cleaning up the old TV pictures, but seldom for soldering.

But if I had to do this every day, or even every week, I would likely invest in a purpose-built device from a reliable maker and reliable source. As I am fond of writing: The Internet is your friend!

Peter Wieck
Melrose Park, PA

Ralph Mowery January 13th 21 04:11 PM

Reviewing a cheap CRT degaussing wand
 
In article ,
says...

For a one-off use, I would likely stick to the soldering gun - does the trick, even if used "off-label". I bring my 100/300 watt Craftsman gun to Kutztown for the occasional chassis connection, and it is as often as not borrowed by the TV guys for cleaning up the old TV pictures, but seldom for soldering.

But if I had to do this every day, or even every week, I would likely invest in a purpose-built device from a reliable maker and reliable source. As I am fond of writing: The Internet is your friend!




I thought most crt screens had a coil around then that helped degauss
them every time they are turned on. Unless someone puts a magnet near
the screen I doubt that many would need degausing.

With almost everything switching to the flat screens there is probably
very little need for a dedicated degausing coil unless your shop
specilizes in restoring old electronics. Hard for me to see any shop or
one doing much work would not have a soldering gun that could be used.
Maybe many do not know the soldering gun could be used.

Peter W. January 13th 21 04:57 PM

Reviewing a cheap CRT degaussing wand
 
I thought most crt screens had a coil around then that helped degauss
them every time they are turned on. Unless someone puts a magnet near
the screen I doubt that many would need degausing.


They do. And, whereas I am not in the vintage CRT hobby, there are any number of applications and any number of reasons why the on-board degausser may not be there, adequate, or even functional. There was (RIP) an individual not far away whose hobby was restoring video arcade games - commercial grade - with the big Curtis-Mathis CRTs in them. And he had half-a-dozen (at least) degaussers of various types and natures that he used regularly. But, apparently, failure of the on-board degausser was common enough that he was prepared.

I keep some small, but very powerful magnets with me most of the time - is that painted pipe steel, copper, or possibly something else? Or that light can? What grade stainless *might* that be? And they will stick to most flat-screens - but not cause any distortion. But get one within 10" or so of the big Sony 32" CRT TV (c. 2001) at home and watch the show. Of course, the on-board coil works on that one, still.

Peter Wieck
Melrose Park, PA


amdx January 13th 21 07:54 PM

Reviewing a cheap CRT degaussing wand
 
On 1/13/2021 9:11 AM, Ralph Mowery wrote:
In article ,
says...
For a one-off use, I would likely stick to the soldering gun - does the trick, even if used "off-label". I bring my 100/300 watt Craftsman gun to Kutztown for the occasional chassis connection, and it is as often as not borrowed by the TV guys for cleaning up the old TV pictures, but seldom for soldering.

But if I had to do this every day, or even every week, I would likely invest in a purpose-built device from a reliable maker and reliable source. As I am fond of writing: The Internet is your friend!



I thought most crt screens had a coil around then that helped degauss
them every time they are turned on. Unless someone puts a magnet near
the screen I doubt that many would need degausing.

With almost everything switching to the flat screens there is probably
very little need for a dedicated degausing coil unless your shop
specilizes in restoring old electronics. Hard for me to see any shop or
one doing much work would not have a soldering gun that could be used.
Maybe many do not know the soldering gun could be used.


Â*30+ years ago, I put two automotive speakers with big magnets near my
TV. It caused a problem on both sides of the screen.

Turning it on and off, hoping the internal degausser would fix didn't.
Even waiting for the PTC to cool.

I used my soldering gun and that fixed it.

I found this at $48,

https://www.zoro.com/gc-electronics-...gclsrc =3p.ds
Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â*Â* Â*Â*Â*Â*Â* Mikek



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Phil Allison[_3_] January 13th 21 10:47 PM

Reviewing a cheap CRT degaussing wand
 
Ralph Mowery wrote:
=================


I thought most crt screens had a coil around then that helped degauss
them every time they are turned on. Unless someone puts a magnet near
the screen I doubt that many would need degausing.


** Correct = ALL crt colour TVs and monitors have automatic degaussing at switch on.
Most monitors have user operated de-gaussing as well.

TV techs may need a de-gausser for that rare event you mentioned .

Maybe many do not know the soldering gun could be used.


** Such guns are getting hard to find.
Demand is so low, few wholesalers stock them.

...... Phil

Ralph Mowery January 14th 21 12:02 AM

Reviewing a cheap CRT degaussing wand
 
In article ,
says...

** Correct = ALL crt colour TVs and monitors have automatic degaussing at switch on.
Most monitors have user operated de-gaussing as well.

TV techs may need a de-gausser for that rare event you mentioned .

Maybe many do not know the soldering gun could be used.


** Such guns are getting hard to find.
Demand is so low, few wholesalers stock them.



Except for the shops that restore old devices with CRTs in them I doubt
that very many shops even work on the CRT units. You can buy some of
the newer LCDs for what it would cost for many shops to look at the
older sets of the same size screens. I am not sure if any TV sets that
had the CRTs in them are even capabile of the new format of the TV
signals with out a converter.

I do know of one man and wife that still use the old set with the
satalite dish. To top it all off he was an electronics engineer with
the Bell and Western Electric system. He is 80 years old and somehow
seems to mostly be stuck in the years before transistors. He is a ham
radio operator and has much gear produced from about 1930 to 1970 and
can work on that with no problem.

Local wholesellers may not stock them,but there are plenty on the
internet. Even Home Depot has them for about $ 45. About 5 years ago I
bought just the replacement housing for a gun I have had over 50 years.
I had dropped it several times during that time and the last time
finished off the housing. As just a hobbiest I do not use one very
much, but do not see how I could get along with out one. I do use the
SMD rework hot air and small iron most of the time.

You did jog my memory. I remember monitors that had the degauss switch
on them. They probably put that on them as many of the computers did
have speakers with magnets close to the screen.



Phil Allison[_3_] January 14th 21 02:15 AM

Reviewing a cheap CRT degaussing wand
 
Ralph Mowery wrote:
==================

You did jog my memory. I remember monitors that had the degauss switch
on them. They probably put that on them as many of the computers did
have speakers with magnets close to the screen.


** Never seen a PC speaker that did NOT use shielded magnets on the drivers.

FYI Consists of a second ferrite ring magnet to cancel external fields - plus a steel cover..


...... Phil

whit3rd January 15th 21 06:10 AM

Reviewing a cheap CRT degaussing wand
 
On Tuesday, January 12, 2021 at 10:47:08 PM UTC-8, John Robertson wrote:
On 2021/01/12 4:56 p.m., Rayner Lucas wrote:
In article ,
says...

In article ,


I use a large Weller Soldering Gun when I can't find one of the
degaussing coils in the shop...


You need something that puts out a large AC field - like the unshielded
transformer used in soldering guns.


Some soldering guns use a hairpin winding on a toroid core; those do NOT give
external field, they're self-shieding, but a 5" diameter simple wire loop connected instead of the
short tip will do a degaussing task adequately.

Phil Allison[_3_] January 17th 21 06:34 AM

Reviewing a cheap CRT degaussing wand
 
whit3rd wrote:

==============

Some soldering guns use a hairpin winding on a toroid core; those do NOT give
external field, they're self-shieding, but a 5" diameter simple wire loop connected instead of the
short tip will do a degaussing task adequately.


** I have read that a magnet attached to the chuck of a power drill, running at high speed, can also be used to demag a TV tube.

Never tried it - seems a bit dodgy.



....... Phil

Rob[_40_] January 17th 21 07:26 PM

Reviewing a cheap CRT degaussing wand
 
Rayner Lucas wrote:
Hi all. This post is a review of the cheap "green stick" CRT degaussing
wands, as I haven't found much discussion of them and some other
repairers of vintage monitors may find it useful.

CRT degaussing tools seem to be hard to find these days.


Small wonder, as hardly anyone uses a CRT these days...
Normally when a CRT TV needs some form of repair, it will join its
fellows in the recycling bin.

[email protected] January 17th 21 11:02 PM

Reviewing a cheap CRT degaussing wand
 
On Sunday, January 17, 2021 at 12:34:53 AM UTC-5, wrote:
whit3rd wrote:

==============

Some soldering guns use a hairpin winding on a toroid core; those do NOT give
external field, they're self-shieding, but a 5" diameter simple wire loop connected instead of the
short tip will do a degaussing task adequately.

** I have read that a magnet attached to the chuck of a power drill, running at high speed, can also be used to demag a TV tube.

Never tried it - seems a bit dodgy.



I can envision some Einstein attaching a magnet to a drill with cellophane tape, and watching in stunned horror as the magnet flies off and smashes the glass top coffee table..




John Robertson January 18th 21 01:11 AM

Reviewing a cheap CRT degaussing wand
 
On 2021/01/17 2:02 p.m., wrote:
On Sunday, January 17, 2021 at 12:34:53 AM UTC-5, wrote:
whit3rd wrote:

==============

Some soldering guns use a hairpin winding on a toroid core; those do NOT give
external field, they're self-shieding, but a 5" diameter simple wire loop connected instead of the
short tip will do a degaussing task adequately.

** I have read that a magnet attached to the chuck of a power drill, running at high speed, can also be used to demag a TV tube.

Never tried it - seems a bit dodgy.


You think? Seems an understatement for you, Phil...


I can envision some Einstein attaching a magnet to a drill with cellophane tape, and watching in stunned horror as the magnet flies off and smashes the glass top coffee table..


Or explodes the picture tube!

John :-#(#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

Mike Coon[_2_] January 18th 21 11:25 PM

Reviewing a cheap CRT degaussing wand
 
In article ,
says...

On 2021/01/17 2:02 p.m., wrote:
On Sunday, January 17, 2021 at 12:34:53 AM UTC-5, wrote:
whit3rd wrote:

I can envision some Einstein attaching a magnet to a drill with

cellophane tape, and watching in stunned horror as the magnet flies off
and smashes the glass top coffee table..


Or explodes the picture tube!

John :-#(#


I used to walk to school (in the 1950s) beside a canal in Bristol (UK).
There was a girder footbridge over this canal, and small kids had
somehow acquired duff CRTs and would carry them half across this bridge
in order to watch them smash into the water. Happy to say I never
actually saw a child burst one on the girders...

Phil Allison[_3_] January 19th 21 01:39 AM

Reviewing a cheap CRT degaussing wand
 
Mike Coon wrote:
=============

Or explodes the picture tube!


There was a girder footbridge over this canal, and small kids had
somehow acquired duff CRTs and would carry them half across this bridge
in order to watch them smash into the water.

-------------------------------

** One saw a pic of a B&W picture tube that had imploded.
The electron gun had been propelled though the screen and imbeded itself in the back of a lounge chair.

There is almost 20,000lbs of pressure on the out side of a 23inch one..

....... Phil

Mike Garcia January 22nd 21 08:14 AM

Reviewing a cheap CRT degaussing wand
 
On Tue, 12 Jan 2021 20:48:30 +0000, Rayner Lucas wrote:

Hi all. This post is a review of the cheap "green stick" CRT degaussing


Nice post!
Good to know!


--

Mike Garcia
http://mgarcia.org


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