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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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TVs and unshielded speakers
What kind of damage can be done to CRT TVs from unshielded speakers?
Do boomboxes from around 2002 usually have shielded or unshielded speakers? |
#2
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TVs and unshielded speakers
On May 21, 10:59*pm, Jo wrote:
What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? Television CRTs have internal elements (shadow mask and electrodes) that can be misaligned, bent, or damaged by a strong magnet. Speakers usually have strong magnets, BUT those are for the voice coil and the field doesn't extend beyond an inch or two. A few compact speakers may have enough field outside the box to distort a color picture (but that doesn't mean that there's any permanent damage), but only if you disassemble the speaker will you get any magnetic parts capable of doing real, permanent damage. All speaker magnet designs are shielded by design, because it's expensive to waste the field on empty space... I've tested magnetic linear motors (big 'uns, over 20 pounds of magnet material) and the field is harmless at a few inches. For a boombox speaker, maybe two inches magnet-to-screen is too close. Four inches should be OK. |
#3
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TVs and unshielded speakers
What kind of damage can be done to CRT TVs from unshielded
speakers? Little or none. Several years ago, as an experiment, I shut off a powerful bulk tape eraser right to a 36" Trinitron to see what happened. It produced what was apparently a permanent color splotch that would not go away, no matter what I did. When the set was moved to my bedroom in March, the splotch magically vanished. I was told that my original "abuse" has caused the aperture grill wires to "tangle", and that moving (and therefore vibrating) the set had made them come loose. In fact, Sony had a guy on the production line who whacked CRTs with a rubber mallet to prevent or reverse this. A TV set's automatic degaussing coil can remove all but the worst magnetization from the shadow mask. It simply isn't something to worry about. Another poster said "All speaker magnet designs are shielded by design, because it's expensive to waste the field on empty space." This is misleading. Simply blocking the external magnetic field does not make it available to strengthen the field around the voice coil. Rather, many, if not most, speaker magnets are "shielded" by using two magnets, arranged so that their fields add at the voice coil, but largely cancel outside. |
#4
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TVs and unshielded speakers
On 22 May, 06:05, "William Sommerwerck"
wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Little or none. Several years ago, as an experiment, I shut off a powerful bulk tape eraser right to a 36" Trinitron to see what happened. It produced what was apparently a permanent color splotch that would not go away, no matter what I did. When the set was moved to my bedroom in March, the splotch magically vanished. I was told that my original "abuse" has caused the aperture grill wires to "tangle", and that moving (and therefore vibrating) the set had made them come loose. In fact, Sony had a guy on the production line who whacked CRTs with a rubber mallet to prevent or reverse this. A TV set's automatic degaussing coil can remove all but the worst magnetization from the shadow mask. It simply isn't something to worry about. Another poster said "All speaker magnet designs are shielded by design, because it's expensive to waste the field on empty space." This is misleading. Simply blocking the external magnetic field does not make it available to strengthen the field around the voice coil. Rather, many, if not most, speaker magnets are "shielded" by using two magnets, arranged so that their fields add at the voice coil, but largely cancel outside. Last night I realized there was a green spot at the top of my TV screen. That's when I realized some jerk had put their boombox right on top the TV earlier in the day. There's two inches between the spot and the top of the TV. So the speaker in the boombox was probably three to four inches away from the spot. It seems like that boombox is what caused the green spot. It would be too much of a coincidence for the spot to appear the same day the boombox had been placed on the TV. So, will this go away by itself? It sounds like you're saying the degaussing thing should fix it. I would imagine something like this would void the warranty and the free repair program thing I purchased. |
#5
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TVs and unshielded speakers
Last night I realized there was a green spot at the top of my TV
screen. That's when I realized some jerk had put their boombox right on top the TV earlier in the day. There's two inches between the spot and the top of the TV. So the speaker in the boombox was probably three to four inches away from the spot. It seems like that boombox is what caused the green spot. It would be too much of a coincidence for the spot to appear the same day the boombox had been placed on the TV. So, will this go away by itself? It sounds like you're saying the degaussing thing should fix it. I would imagine something like this would void the warranty and the free repair program thing I purchased. There's no reason you would need an external degaussing coil. * The next time you turn it on, its built-in degaussing system should clear the magnetization. And if you did use an external demagnetizer, the manufacturer would have no way of knowing. * As flat-panel displays displace CRTs, degaussing coils will become the proverbial hen's teeth. |
#6
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TVs and unshielded speakers
On Fri, 22 May 2009 13:09:06 -0700, William Sommerwerck wrote:
Last night I realized there was a green spot at the top of my TV screen. That's when I realized some jerk had put their boombox right on top the TV earlier in the day. There's two inches between the spot and the top of the TV. So the speaker in the boombox was probably three to four inches away from the spot. It seems like that boombox is what caused the green spot. It would be too much of a coincidence for the spot to appear the same day the boombox had been placed on the TV. So, will this go away by itself? It sounds like you're saying the degaussing thing should fix it. I would imagine something like this would void the warranty and the free repair program thing I purchased. There's no reason you would need an external degaussing coil. * The next time you turn it on, its built-in degaussing system should clear the magnetization. And if you did use an external demagnetizer, the manufacturer would have no way of knowing. They are only strong enough to counter the earth's magnetic field. If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Use a bulk tape eraser. |
#7
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TVs and unshielded speakers
They are only strong enough to counter the earth's magnetic field.
If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? |
#8
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TVs and unshielded speakers
On Fri, 22 May 2009 13:58:53 -0700, William Sommerwerck wrote:
They are only strong enough to counter the earth's magnetic field. If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? I have on several TV's and monitors. I used to play with magnets and have never seen any degauser remove the slightest spot. Bulk tape erasers work although you have to back off slowly before killing the power or they'll leave new spots. Why the don't you try it yourself before making more of an ass of yourself? |
#9
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TVs and unshielded speakers
"AZ Nomad" wrote in message
... On Fri, 22 May 2009 13:58:53 -0700, William Sommerwerck wrote: They are only strong enough to counter the earth's magnetic field. If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? I have on several TV's and monitors. I used to play with magnets and have never seen any degauser remove the slightest spot. Bulk tape erasers work although you have to back off slowly before killing the power or they'll leave new spots. Why the don't you try it yourself before making more of an ass of yourself? I've done it. And it works. |
#10
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TVs and unshielded speakers
Jo wrote:
What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. |
#11
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TVs and unshielded speakers
"William Sommerwerck" wrote in
: Last night I realized there was a green spot at the top of my TV screen. That's when I realized some jerk had put their boombox right on top the TV earlier in the day. There's two inches between the spot and the top of the TV. So the speaker in the boombox was probably three to four inches away from the spot. It seems like that boombox is what caused the green spot. It would be too much of a coincidence for the spot to appear the same day the boombox had been placed on the TV. So, will this go away by itself? It sounds like you're saying the degaussing thing should fix it. I would imagine something like this would void the warranty and the free repair program thing I purchased. There's no reason you would need an external degaussing coil. * The next time you turn it on, its built-in degaussing system should clear the magnetization. And if you did use an external demagnetizer, the manufacturer would have no way of knowing. * As flat-panel displays displace CRTs, degaussing coils will become the proverbial hen's teeth. I used to work on TEK 650 series video monitors(TEK service centers),and we used an external degaussing coil,called for in the calibration procedure. The internal 'DG' coils are not as strong as the external ones,and you have to move them around the face of the tube,you cant do that with the internal coil. TV repair shops all used them,made good money degaussing TVs people had screwed up with magnets. It should not affect your warranty. -- Jim Yanik jyanik at kua.net |
#12
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TVs and unshielded speakers
"William Sommerwerck" wrote in
: "AZ Nomad" wrote in message ... On Fri, 22 May 2009 13:58:53 -0700, William Sommerwerck wrote: They are only strong enough to counter the earth's magnetic field. If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? I have on several TV's and monitors. I used to play with magnets and have never seen any degauser remove the slightest spot. Bulk tape erasers work although you have to back off slowly before killing the power or they'll leave new spots. that's the way you do it with an external TV degaussing coil.You work the coil around the CRT face several times,gradually back away until you're a few feet away and -then- click off the coil. Why the don't you try it yourself before making more of an ass of yourself? I've done it. And it works. -- Jim Yanik jyanik at kua.net |
#13
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TVs and unshielded speakers
If you put a magnet close enough to magnetize the CRT, the
degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? I have on several TV's and monitors. I used to play with magnets and have never seen any degauser remove the slightest spot. Bulk tape erasers work although you have to back off slowly before killing the power or they'll leave new spots. that's the way you do it with an external TV degaussing coil.You work the coil around the CRT face several times,gradually back away until you're a few feet away and -then- click off the coil. Why the don't you try it yourself before making more of an ass of yourself? I've done it. And it works. And now that the trade secret is out... A blowdrier might be a fair substitute, or even a wall-wort on a long extension cord. Another possibility is purity magnets getting thrown off by being remangnitized. Might need a degauss of the entire chassis followed up by purity and convergence alignment. Speakers and TVs don't mix. |
#14
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TVs and unshielded speakers
In article ,
Sjouke Burry wrote: Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. |
#15
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TVs and unshielded speakers
Smitty Two wrote:
In article , Sjouke Burry wrote: Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. Done that a number of times, moving furniture around. I have never seen localized color errors, except when I was fooling around with some magnets, mainly from old diskdrives. The de-gausing build into my tv took care of the results of those experiments |
#16
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TVs and unshielded speakers
What kind of damage can be done to CRT TVs from unshielded
speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my CRT TV as we speak. Has been there for the last 10 years. No problem. Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. In fairness, I was claiming that the internal degaussing coil would be sufficient. (It's generally more powerful than would be needed simply to clear the magnetization induced by moving the set through the Earth's magnetic field.) I stand by that, but it's certainly true that the shadow mask could be so badly magnetized that a more-powerful external coil would be needed. My 36" Sony WEGA sat between two Apogee Diva speakers. There was no visible impurity from the speakers. On one occasion, when I had to move the right-front speaker to re-glue the midrange ribbon, all sorts of colorations appeared on the screen. They pretty much disappeared when the speaker was returned to its usual position. If you bring a big magnet near the CRT, then move it away in the same direction it arrived, much of the induced magnetization will be removed. To put it another way -- you have to go out of your way to badly magnetize a shadow mask. If you remember the example I gave, despite having shut off a very powerful bulk eraser right next to the CRT, I hadn't permanently magnetized the aperture grille -- simply knocked it out of alignment. Do any of you remember Zenith's spinning wand? It was a small bar magnet that could be spun by hand. The idea was to allow demagnetizing small areas without having to plug in a coil. |
#17
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TVs and unshielded speakers
AZ Nomad wrote: On Fri, 22 May 2009 13:58:53 -0700, William Sommerwerck wrote: They are only strong enough to counter the earth's magnetic field. If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? I have on several TV's and monitors. I used to play with magnets and have never seen any degauser remove the slightest spot. Bulk tape erasers work although you have to back off slowly before killing the power or they'll leave new spots. Why the don't you try it yourself before making more of an ass of yourself? Too strong of a magnetic field from that bulk tape eraser can warp the shadow mask It can even pull it loose inside the bell. I've seen the damage on some CRTs, but its yours to destroy. I've degaussed thousands of CRTs in the last 40+ years. -- You can't have a sense of humor, if you have no sense! |
#18
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TVs and unshielded speakers
Smitty Two wrote:
In article , Sjouke Burry wrote: Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. Did it have a loco or two on the track? with permanent magnets in the motors? Ron |
#19
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TVs and unshielded speakers
In message , Sjouke Burry
writes Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. Some of the worst offenders are the small speakers used for car hands-free telephone installations. They are powerful little fellows, and can affect CRT pictures from a distance of more than 18". They are not exactly hi-fi, but are sometimes used as external speakers for CB and amateur radio equipment, and must be kept well away from any TV set in the vicinity. -- Ian |
#20
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TVs and unshielded speakers
On May 22, 7:43*pm, Smitty Two wrote:
In article , *Sjouke Burry wrote: Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. Just to be clear: a magnet outside the TV can magnetize a bit of steel inside the TV, so it takes BOTH moving the source AND cycling the TV's internal degaussing coil to rid oneself of the color. Unplug the TV for at least 5 minutes to be sure it's cold, then plug it in and turn it on, to trigger the degausser cycle. This should be done if magnetized items are moved to or from the TV's vicinity, or even (for careful work) when the compass orientation of the TV is changed. Any color splotches that remain, require purity magnet adjustment (if you have to ask what that means, you should let someone else do it). |
#21
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TVs and unshielded speakers
On 5/23/2009 2:49 AM Ron spake thus:
Smitty Two wrote: In article , Sjouke Burry wrote: Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. Did it have a loco or two on the track? with permanent magnets in the motors? Real loco motors (i.e., traction motors) don't have magnets. Use field coils. -- Found--the gene that causes belief in genetic determinism |
#22
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TVs and unshielded speakers
David Nebenzahl wrote:
On 5/23/2009 2:49 AM Ron spake thus: Smitty Two wrote: In article , Sjouke Burry wrote: Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A boom box is sitting right under my crt tv as we speak. Has been there for the last 10 years. No problem. Would you humor me with an experiment? Move the boombox away, and see whether the picture changes, then put it back. I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. Did it have a loco or two on the track? with permanent magnets in the motors? Real loco motors (i.e., traction motors) don't have magnets. Use field coils. Oh, I thought we were talking about model railway track - I doubt he could have got a 'Real Loco' on top of his TV Why whould you put a length of... oh never mind (I used to have a conrod and piston on top of mine) Ron |
#23
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TVs and unshielded speakers
In article ,
Ron wrote: David Nebenzahl wrote: On 5/23/2009 2:49 AM Ron spake thus: Smitty Two wrote: I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. Did it have a loco or two on the track? with permanent magnets in the motors? Real loco motors (i.e., traction motors) don't have magnets. Use field coils. Oh, I thought we were talking about model railway track - I doubt he could have got a 'Real Loco' on top of his TV Why whould you put a length of... oh never mind (I used to have a conrod and piston on top of mine) Ron Yeah, real track. 50 or 100 lbs. of steel, I don't remember quite how heavy it was. OT: You gotta hand it to Lionel's founder, Joshua Lionel Cowen. A real marketing genius. He referred to the real trains on which his toys were modeled as "prototypes." |
#24
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TVs and unshielded speakers
In article , whit3rd wrote:
On May 21, 10:59=A0pm, Jo wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? Television CRTs have internal elements (shadow mask and electrodes) that can be misaligned, bent, or damaged by a strong magnet. Speakers usually have strong magnets, BUT those are for the voice coil and the field doesn't extend beyond an inch or two. A few compact You must not have played around much with speakers. Even the shielded ones have a little effect, and it also depends how well the drivers are made and the shielding they employ. Its easy to see effects of unshielded speakers from a foot ot two away. When drivers are made, they can be designed to have minimal external fields before shielding. Its a manufacturing design cost thing. greg speakers may have enough field outside the box to distort a color picture (but that doesn't mean that there's any permanent damage), but only if you disassemble the speaker will you get any magnetic parts capable of doing real, permanent damage. All speaker magnet designs are shielded by design, because it's expensive to waste the field on empty space... I've tested magnetic linear motors (big 'uns, over 20 pounds of magnet material) and the field is harmless at a few inches. For a boombox speaker, maybe two inches magnet-to-screen is too close. Four inches should be OK. |
#25
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TVs and unshielded speakers
On May 22, 6:59*am, Jo wrote:
What kind of damage can be done to CRT TVs from unshielded speakers? Do boomboxes from around 2002 usually have shielded or unshielded speakers? A strong magnetic field close to a CRT tv or monitor could magnetise the steel shadow mask. This will lead to purity errors or splodges of colour as the beams are diverted from their usual path, hitting the wrong phosphors. All CRT's have a degauzing circuit built around the tube, which will only operate from cold - so leave set off for five mins before trying. The shadowmask is allowed to move as it heats up, they can dissipate many watts, so it is unlikely to distort unless an extremely powerfull magnet is placed right on the screen. Usually only happens when it has been dropped. If the internal degauzing cct does not do the job then a degauzing wand or similar ( a coil with alternating magnetic field) is used. this you have to start close to the set and move away while rotating untill you are out of range. inverse square law applies. speakers from2002 that are used for A/V will certainly(almost) to be sheilded. |
#26
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TVs and unshielded speakers
"Smitty Two" wrote in message news In article , Ron wrote: David Nebenzahl wrote: On 5/23/2009 2:49 AM Ron spake thus: Smitty Two wrote: I once put a 30" length of railroad rail on top of my TV. You know, a bachelor's idea of home decorating. It sat there for a few years, and never caused any problem with the picture. When I finally moved it, the color blotches were horrible. But the external degaussing coil cleared it right up. Did it have a loco or two on the track? with permanent magnets in the motors? Real loco motors (i.e., traction motors) don't have magnets. Use field coils. Oh, I thought we were talking about model railway track - I doubt he could have got a 'Real Loco' on top of his TV Why whould you put a length of... oh never mind (I used to have a conrod and piston on top of mine) Ron Yeah, real track. 50 or 100 lbs. of steel, I don't remember quite how heavy it was. OT: You gotta hand it to Lionel's founder, Joshua Lionel Cowen. A real marketing genius. He referred to the real trains on which his toys were modeled as "prototypes." Don't tell me... This was to stop the buzz from the internal speaker grill? Why not bend the track and wheel the TV around on it? |
#27
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TVs and unshielded speakers
JB wrote: Don't tell me... This was to stop the buzz from the internal speaker grill? Why not bend the track and wheel the TV around on it? 50 - 100 pounds would only be a few feet of standard rail used in the US. I had a one foot piece of scrap rail someone had ground into a crude anvil that weighed 45 pounds. -- You can't have a sense of humor, if you have no sense! |
#28
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TVs and unshielded speakers
In article ,
"JB" wrote: Don't tell me... This was to stop the buzz from the internal speaker grill? Nah, just home decor. I had a few pieces of railroad junk lying around. I had actually just sold the TV when I removed the rail and the colors went haywire. They buyer got real nervous, but I hit it with my degaussing coil and cleared it right up. I guess the rail had become part of the magnetic field of the CRT, gradually over time. |
#29
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TVs and unshielded speakers
Jo wrote:
What kind of damage can be done to CRT TVs from unshielded speakers? Nothing that can't be fixed with a degaussing wand. If the colours on your screen are distorting, your speakers are too close. Do boomboxes from around 2002 usually have shielded or unshielded speakers? Unshielded, most likely. -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
#30
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TVs and unshielded speakers
Jo wrote:
On 22 May, 06:05, "William Sommerwerck" wrote: What kind of damage can be done to CRT TVs from unshielded speakers? Little or none. Several years ago, as an experiment, I shut off a powerful bulk tape eraser right to a 36" Trinitron to see what happened. It produced what was apparently a permanent color splotch that would not go away, no matter what I did. When the set was moved to my bedroom in March, the splotch magically vanished. I was told that my original "abuse" has caused the aperture grill wires to "tangle", and that moving (and therefore vibrating) the set had made them come loose. In fact, Sony had a guy on the production line who whacked CRTs with a rubber mallet to prevent or reverse this. A TV set's automatic degaussing coil can remove all but the worst magnetization from the shadow mask. It simply isn't something to worry about. Another poster said "All speaker magnet designs are shielded by design, because it's expensive to waste the field on empty space." This is misleading. Simply blocking the external magnetic field does not make it available to strengthen the field around the voice coil. Rather, many, if not most, speaker magnets are "shielded" by using two magnets, arranged so that their fields add at the voice coil, but largely cancel outside. Last night I realized there was a green spot at the top of my TV screen. That's when I realized some jerk had put their boombox right on top the TV earlier in the day. There's two inches between the spot and the top of the TV. So the speaker in the boombox was probably three to four inches away from the spot. It seems like that boombox is what caused the green spot. It would be too much of a coincidence for the spot to appear the same day the boombox had been placed on the TV. So, will this go away by itself? Eventually. It sounds like you're saying the degaussing thing should fix it. Yes. Eventually. Each time you power-cycle the TV, it should fade, or even go away. You can fix it in one go with a degaussing wand, but that's probably overkill for a small splotch. I would imagine something like this would void the warranty and the free repair program thing I purchased. Nah, if they don't see it themselves & you're not silly enough to tell them, it'll be fine. -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
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TVs and unshielded speakers
William Sommerwerck wrote:
They are only strong enough to counter the earth's magnetic field. If you put a magnet close enough to magnetize the CRT, the degauser will probably never be able to undo it. Have you ever tried it? Or are you just theorizing? Why don't you actually do it, then report back what you find? nods From experience, I've found that the TVs own degaussing coil can deal with a surprising amount of magnetisation. -- W . | ,. w , "Some people are alive only because \|/ \|/ it is illegal to kill them." Perna condita delenda est ---^----^--------------------------------------------------------------- |
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