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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
Posted to sci.electronics.repair
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Hissing TV.
OK so it was hissing, I see blue arcing on the tube on the cap,
is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? |
#2
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Hissing TV.
"Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. |
#3
Posted to sci.electronics.repair
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Hissing TV.
"Colin Trunt" wrote in
: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. all that tobacco smoke residue is the problem..... just think,that gunk is all over the inside of your lungs,too. -- Jim Yanik jyanik at localnet dot com |
#4
Posted to sci.electronics.repair
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Hissing TV.
"Jim Yanik" wrote in message 4... "Colin Trunt" wrote in : "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. all that tobacco smoke residue is the problem..... just think,that gunk is all over the inside of your lungs,too. Wel you are right, however if it colledted in my lungs like it does on a TV tube I would be dead many years ago. Obviously not doing me any good physically, but mentally it makes me feel a lot better, so swings and roundabouts. No point in having great lungs if you are swinging from the light fitting :O) -- Jim Yanik jyanik at localnet dot com |
#5
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! |
#6
Posted to sci.electronics.repair
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Hissing TV.
Meat Plow wrote: Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. This is what 'Corona Dope' was created for. -- The movie 'Deliverance' isn't a documentary! |
#7
Posted to sci.electronics.repair
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Hissing TV.
Meat Plow wrote: Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. This is what 'Corona Dope' was created for. -- The movie 'Deliverance' isn't a documentary! |
#8
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Thu, 29 Oct 2009 17:38:55 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If your white silicone is 100% silicone that would work too. But if it isn't arcing it doesn't need more cleaning or silicone. The damage is done and you probably need a focus divider or whatever on your particular set provides the focus grid inside the CRT with voltage. I think when it I first switch it on it may be arcing and hissing a little, it was not like the arcing which I had before I cleaned it (or cleaned a smaller area) where you could see a fairly distinctive arc, but rather more of a sort of 'glow' over the top of part of the tube. There was an area which was sort of 'illuminated). Actualy it may have been several 'mini-arcs' certainlty the curve of the tube would make a straight one impossible, maybe if I clean it better, it will help. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Still blurred when I switched on, then after a while the picture started narrowing (going widescreen so to speak!!). What would cause that? Anyway I switched it off again and had another go at drying it, put it back on and it was back to full screen and not as blured, it was soon back to unblurred, but it had had a bit of a 'warm up' from earlier. Picture is good now ie full screen and sharp, I don't think it will 'collapse in' again. I will see what it is like when it has been off over night to access what difference it made. |
#9
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Thu, 29 Oct 2009 17:38:55 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If your white silicone is 100% silicone that would work too. But if it isn't arcing it doesn't need more cleaning or silicone. The damage is done and you probably need a focus divider or whatever on your particular set provides the focus grid inside the CRT with voltage. I think when it I first switch it on it may be arcing and hissing a little, it was not like the arcing which I had before I cleaned it (or cleaned a smaller area) where you could see a fairly distinctive arc, but rather more of a sort of 'glow' over the top of part of the tube. There was an area which was sort of 'illuminated). Actualy it may have been several 'mini-arcs' certainlty the curve of the tube would make a straight one impossible, maybe if I clean it better, it will help. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Still blurred when I switched on, then after a while the picture started narrowing (going widescreen so to speak!!). What would cause that? Anyway I switched it off again and had another go at drying it, put it back on and it was back to full screen and not as blured, it was soon back to unblurred, but it had had a bit of a 'warm up' from earlier. Picture is good now ie full screen and sharp, I don't think it will 'collapse in' again. I will see what it is like when it has been off over night to access what difference it made. |
#10
Posted to sci.electronics.repair
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Hissing TV.
On Oct 29, 10:38*am, "Colin Trunt" wrote:
"Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? *Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If you're thinking silicone bathroom caulk, that stuff is conductive until it's cured. This is the stuff we use when replacing a CRT. A bead of it (it never hardens) around the anode terminal under the rubber cap does the trick. http://www.newark.com/jsp/search/pro...C-QO1721829242 G² |
#11
Posted to sci.electronics.repair
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Hissing TV.
On Oct 29, 10:38*am, "Colin Trunt" wrote:
"Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? *Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If you're thinking silicone bathroom caulk, that stuff is conductive until it's cured. This is the stuff we use when replacing a CRT. A bead of it (it never hardens) around the anode terminal under the rubber cap does the trick. http://www.newark.com/jsp/search/pro...C-QO1721829242 G² |
#12
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Hissing TV.
I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. Snip I guess the only action I can take is to clean it throughly. Snip The area I didn't clean look black but the clean are alooks pretty OK. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Snip Just how much of a "cleaning" are you doing? You do realize the black stuff coating the outside (aquadag) is a functional part of the tube. JC |
#13
Posted to sci.electronics.repair
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Hissing TV.
Meat Plow wrote: On Thu, 29 Oct 2009 17:38:17 -0400, "Michael A. Terrell" wrote: Meat Plow wrote: Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. This is what 'Corona Dope' was created for. Really? Gee Wiz I've never heard of that kinda Dope. You tried to smoke it. -- The movie 'Deliverance' isn't a documentary! |
#14
Posted to sci.electronics.repair
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Hissing TV.
Meat Plow wrote: On Thu, 29 Oct 2009 17:38:17 -0400, "Michael A. Terrell" wrote: Meat Plow wrote: Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. This is what 'Corona Dope' was created for. Really? Gee Wiz I've never heard of that kinda Dope. You tried to smoke it. -- The movie 'Deliverance' isn't a documentary! |
#15
Posted to sci.electronics.repair
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Hissing TV.
wrote in message ... On Oct 29, 10:38 am, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If you're thinking silicone bathroom caulk, that stuff is conductive until it's cured. This is the stuff we use when replacing a CRT. A bead of it (it never hardens) around the anode terminal under the rubber cap does the trick. http://www.newark.com/jsp/search/pro...C-QO1721829242 G² |
#16
Posted to sci.electronics.repair
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Hissing TV.
"Archon" wrote in message ... I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. Snip I guess the only action I can take is to clean it throughly. Snip The area I didn't clean look black but the clean are alooks pretty OK. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Snip Just how much of a "cleaning" are you doing? You do realize the black stuff coating the outside (aquadag) is a functional part of the tube. JC The tar from the tobacco is not essential I believe. I am not familiar with aquadaq, I am however familiar with tobacco smoke deposits.I don't think I have taken any coating off however I don't remember takking anything off other than tobaccco/dirt. Also I have put the back on the TV so i cant have a look easilly. I did notice when I cleaned a wider area that I could seen a change in colour along a straight line. I don''t think I removed any coating. |
#17
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Fri, 30 Oct 2009 01:16:44 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Thu, 29 Oct 2009 17:38:55 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If your white silicone is 100% silicone that would work too. But if it isn't arcing it doesn't need more cleaning or silicone. The damage is done and you probably need a focus divider or whatever on your particular set provides the focus grid inside the CRT with voltage. I think when it I first switch it on it may be arcing and hissing a little, it was not like the arcing which I had before I cleaned it (or cleaned a smaller area) where you could see a fairly distinctive arc, but rather more of a sort of 'glow' over the top of part of the tube. There was an area which was sort of 'illuminated). Actualy it may have been several 'mini-arcs' certainlty the curve of the tube would make a straight one impossible, maybe if I clean it better, it will help. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Still blurred when I switched on, then after a while the picture started narrowing (going widescreen so to speak!!). What would cause that? Anyway I switched it off again and had another go at drying it, put it back on and it was back to full screen and not as blured, it was soon back to unblurred, but it had had a bit of a 'warm up' from earlier. Picture is good now ie full screen and sharp, I don't think it will 'collapse in' again. I will see what it is like when it has been off over night to access what difference it made. When electronic things get better as they warm it's usually associated with tubes or electrolytic capacitors. Since your TV has only one tube the CRT, it's plausible that it's at fault where focus is concerned. When you first posted your chief complaint was that it took 15 minutes to focus but only after you cleaned the anode cap. How was it before it started hissing? There was no noticiable delay, by the time the picture was visable it was in focus. I am not 100% clear about things but I think maybe that the tape fixed it at first but the next day when I switched on it hissed, I am not sure if it was also blurred, my post seems to indicated it was only blurred after cleaning. However I am not 100% sure of this. I don't see a decent correlation between events here. Some may be coincidental. I don't remember the age or brand of TV either. Was that ever mentioned? TV is about 5 years old. It's a Wharfdale :O) Disturbingly similar to this one http://www.unbeatable.co.uk/product/.../28143603.html Wharfedale CTV2185RF Comes with years guarantee, which is less that you are entitled to under the law of the land - lol. There may be a problem in that if theTV is 'warmed up' doing something to it like cleaninh may not 'take-effect' blurring wise untill the next day. Incidently I had this problem befo- http://groups.google.co.uk/group/sci...pint&lnk=ol & (im half_pint there). Incidently the set did eventually go completely, but I the problem was cured in the meantime, then one day when, I switched on it just 'went', ie went dead, no fireworks that I could see, just the normal click when you switch on then nothing. It worked for a while before it went, but not that long because I have had this one for a while, I also got a portable as a back-up :O). I also have a USB TV stick I can use. I will read up on this flyback stuff to see if I can make sense of it, It might help me understand what is going on. I am wondering if putting the back back on the TV will help things? I won't know untill the TV has been swiched off for a long time. I guess LCD TV's don't have this problem? TV is find at the moment, good picture. I will time the warm up next time it has been off over night. |
#18
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Mon, 2 Nov 2009 11:45:48 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Fri, 30 Oct 2009 01:16:44 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Thu, 29 Oct 2009 17:38:55 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If your white silicone is 100% silicone that would work too. But if it isn't arcing it doesn't need more cleaning or silicone. The damage is done and you probably need a focus divider or whatever on your particular set provides the focus grid inside the CRT with voltage. I think when it I first switch it on it may be arcing and hissing a little, it was not like the arcing which I had before I cleaned it (or cleaned a smaller area) where you could see a fairly distinctive arc, but rather more of a sort of 'glow' over the top of part of the tube. There was an area which was sort of 'illuminated). Actualy it may have been several 'mini-arcs' certainlty the curve of the tube would make a straight one impossible, maybe if I clean it better, it will help. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Still blurred when I switched on, then after a while the picture started narrowing (going widescreen so to speak!!). What would cause that? Anyway I switched it off again and had another go at drying it, put it back on and it was back to full screen and not as blured, it was soon back to unblurred, but it had had a bit of a 'warm up' from earlier. Picture is good now ie full screen and sharp, I don't think it will 'collapse in' again. I will see what it is like when it has been off over night to access what difference it made. When electronic things get better as they warm it's usually associated with tubes or electrolytic capacitors. Since your TV has only one tube the CRT, it's plausible that it's at fault where focus is concerned. When you first posted your chief complaint was that it took 15 minutes to focus but only after you cleaned the anode cap. How was it before it started hissing? There was no noticiable delay, by the time the picture was visable it was in focus. I am not 100% clear about things but I think maybe that the tape fixed it at first but the next day when I switched on it hissed, I am not sure if it was also blurred, my post seems to indicated it was only blurred after cleaning. However I am not 100% sure of this. I don't see a decent correlation between events here. Some may be coincidental. I don't remember the age or brand of TV either. Was that ever mentioned? TV is about 5 years old. It's a Wharfdale :O) Disturbingly similar to this one http://www.unbeatable.co.uk/product/.../28143603.html Wharfedale CTV2185RF Comes with years guarantee, which is less that you are entitled to under the law of the land - lol. There may be a problem in that if theTV is 'warmed up' doing something to it like cleaninh may not 'take-effect' blurring wise untill the next day. Incidently I had this problem befo- http://groups.google.co.uk/group/sci...pint&lnk=ol & (im half_pint there). Incidently the set did eventually go completely, but I the problem was cured in the meantime, then one day when, I switched on it just 'went', ie went dead, no fireworks that I could see, just the normal click when you switch on then nothing. It worked for a while before it went, but not that long because I have had this one for a while, I also got a portable as a back-up :O). I also have a USB TV stick I can use. I will read up on this flyback stuff to see if I can make sense of it, It might help me understand what is going on. I am wondering if putting the back back on the TV will help things? I won't know untill the TV has been swiched off for a long time. I guess LCD TV's don't have this problem? TV is find at the moment, good picture. I will time the warm up next time it has been off over night. You should wait a day after you clean it to power it up. Especially if you use a water based cleaner. And while it's sizzling it probably will effect the focus. I actually tried white spirit first (alcohol) but I don't think it was that good so I used just water next, maybe with some washing up liquid in it. I know tobacco smoke deposits seem to be very water soluble. |
#19
Posted to sci.electronics.repair
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Hissing TV.
Meat Plow wrote: On Fri, 30 Oct 2009 18:02:28 -0400, "Michael A. Terrell" wrote: Meat Plow wrote: On Thu, 29 Oct 2009 17:38:17 -0400, "Michael A. Terrell" wrote: Meat Plow wrote: Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. This is what 'Corona Dope' was created for. Really? Gee Wiz I've never heard of that kinda Dope. You tried to smoke it. Yeh but I caught my face on fire trying. These days I prefer a Corona Dope infusion drip directly into an arterial peripherally inserted central catheter. Sure you do. It's quite toxic that way. i've seen it set on fire when people didn;t let it cure overnight. they would apply it, then power up the TV an half hour later to lots of smoke, and some flames. -- The movie 'Deliverance' isn't a documentary! |
#20
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Mon, 2 Nov 2009 15:14:22 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Mon, 2 Nov 2009 11:45:48 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Fri, 30 Oct 2009 01:16:44 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Thu, 29 Oct 2009 17:38:55 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If your white silicone is 100% silicone that would work too. But if it isn't arcing it doesn't need more cleaning or silicone. The damage is done and you probably need a focus divider or whatever on your particular set provides the focus grid inside the CRT with voltage. I think when it I first switch it on it may be arcing and hissing a little, it was not like the arcing which I had before I cleaned it (or cleaned a smaller area) where you could see a fairly distinctive arc, but rather more of a sort of 'glow' over the top of part of the tube. There was an area which was sort of 'illuminated). Actualy it may have been several 'mini-arcs' certainlty the curve of the tube would make a straight one impossible, maybe if I clean it better, it will help. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Still blurred when I switched on, then after a while the picture started narrowing (going widescreen so to speak!!). What would cause that? Anyway I switched it off again and had another go at drying it, put it back on and it was back to full screen and not as blured, it was soon back to unblurred, but it had had a bit of a 'warm up' from earlier. Picture is good now ie full screen and sharp, I don't think it will 'collapse in' again. I will see what it is like when it has been off over night to access what difference it made. When electronic things get better as they warm it's usually associated with tubes or electrolytic capacitors. Since your TV has only one tube the CRT, it's plausible that it's at fault where focus is concerned. When you first posted your chief complaint was that it took 15 minutes to focus but only after you cleaned the anode cap. How was it before it started hissing? There was no noticiable delay, by the time the picture was visable it was in focus. I am not 100% clear about things but I think maybe that the tape fixed it at first but the next day when I switched on it hissed, I am not sure if it was also blurred, my post seems to indicated it was only blurred after cleaning. However I am not 100% sure of this. I don't see a decent correlation between events here. Some may be coincidental. I don't remember the age or brand of TV either. Was that ever mentioned? TV is about 5 years old. It's a Wharfdale :O) Disturbingly similar to this one http://www.unbeatable.co.uk/product/.../28143603.html Wharfedale CTV2185RF Comes with years guarantee, which is less that you are entitled to under the law of the land - lol. There may be a problem in that if theTV is 'warmed up' doing something to it like cleaninh may not 'take-effect' blurring wise untill the next day. Incidently I had this problem befo- http://groups.google.co.uk/group/sci...pint&lnk=ol & (im half_pint there). Incidently the set did eventually go completely, but I the problem was cured in the meantime, then one day when, I switched on it just 'went', ie went dead, no fireworks that I could see, just the normal click when you switch on then nothing. It worked for a while before it went, but not that long because I have had this one for a while, I also got a portable as a back-up :O). I also have a USB TV stick I can use. I will read up on this flyback stuff to see if I can make sense of it, It might help me understand what is going on. I am wondering if putting the back back on the TV will help things? I won't know untill the TV has been swiched off for a long time. I guess LCD TV's don't have this problem? TV is find at the moment, good picture. I will time the warm up next time it has been off over night. You should wait a day after you clean it to power it up. Especially if you use a water based cleaner. And while it's sizzling it probably will effect the focus. I actually tried white spirit first (alcohol) but I don't think it was that good so I used just water next, maybe with some washing up liquid in it. I know tobacco smoke deposits seem to be very water soluble. Water is a good solvent. Some tars won't dissolve in ethyl alcohol but most will in isopropyl or methyl alcohol. Personally I would have started with testing a small area using a dab of Acetone on a rag. If the surface seemed to tolerate that well then I would have wiped around the anode cap for maybe 50 millimeters then the cap itself provided it too was silicone rubber as Acetone doesn't react with 100% silicone rubber readily. Well...switched on this morning and.... no blurry picture!!! However it was hissing a bit, I can't see no arcing however it's hard to see with the back on, the hissing seems to have stopped now. I thought putting the back on would help, I think the same happened with my last TV but I can' remember clearly. It seems to me it is effecting the capacitance in some way or whatever. I an not sure about all this flyback stuuf and how it works and why the tube is involved. Is the tube used as a smoothing capacitor? Regarding solvents I know water works because I have to clean up smoke deposits else where and I just use water and maybe some detergent., with white spirist everything smells of alcohol. |
#21
Posted to sci.electronics.repair
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Hissing TV.
"Meat Plow" wrote in message ... On Tue, 3 Nov 2009 11:20:52 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Mon, 2 Nov 2009 15:14:22 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Mon, 2 Nov 2009 11:45:48 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Fri, 30 Oct 2009 01:16:44 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Thu, 29 Oct 2009 17:38:55 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message ... On Wed, 28 Oct 2009 21:23:13 -0000, "Colin Trunt" wrote: "Meat Plow" wrote in message .. . On Wed, 28 Oct 2009 12:39:07 -0000, "Colin Trunt" wrote: OK so it was hissing, I see blue arcing on the tube on the cap, is also covered in tobacco smoke/dirt. I tried some insulating tape at first, which worked for a while but not the next day. Anyway I cleaned up around the cap a bit untill I did not get much arcing or any arching. Anyway now when I switch on the picture is blurred, however it gets better and after about 15 minutes it is back to normal or very near to. So how do I make it work from cold, ie no blurred picture. There was also some hissing this morning and some faint arching but that seemed to clear up afer a few minutes. I am thinking cleaning a larger area would help. I am not sure why the picture eventually sorts it self out slowly after switching on. Is something heating up? How was the focus when it was hissing? Often the focus reference is part of the anode voltage circuit and could be strained by the additional current when arcing. Well generally bad, but when it first started hissing I think it was OK it was just the noise which was annoying. Only after my various attempts at cleaning where the arcing was coming from did the out of focus stuff start appearing. There may still have been some arching then but less visable and more silent. What tends to happen is the picture slowly 'unblurs' itself, and the hissing if any goes away. I was king of thinking that cleaning an area disturbed the electrical charastics of the tube, unbalancing it, I though maybe if I cleaned all of the tube it might restore that balance as it would have an even spread of surface charastics. However eventually it does restore focus fully even with an unevenly cleaned tube. I am thinking maybe the surface 'dries out' or the surface charges up to restore an even 'balance'. It is when it has been switch on after a long period off that it is blurred. If I switch it on an off now it remains unblurred because it has 'warmed up'. Incidently I have just started using an old cumputer monitor as a second terminal and I can hear it hissing!! High humitity is part of the problem I think. The picture looks OK maybe a little blured hard to say, it's not very bright though. I guess the only action I can take is to clean it throughly. I mean I have no parts or a soldering iron etc... so thats about all I can do anyway. I wil try giving it a good clean when I have the time. Thanks for your input. Watch the anode hole on the CRT, it will store high voltage and will shock you. Running a bead of silicone rubber around the outside of the cap on the CRT surface can stop arcs if the surface of the CRT is carbon etched from arcing. Not sure if I have any silicone rubber or not, or indeed what it is :O) I might have some plumbers white silicon stuff though. I was wondering about the cap, as I had lifted it up, I was wondering if I meeded to clean under it. I saw the wires that go to the anode and I thought maybe I had disturbed the position of the anode, but obviously not as that would not selfright itself. The area I didn't clean look black but the clean are alooks pretty OK. It's not a mojor problem though, I normally switch it on beforeI want to watch it so by the time I do the picture is perfectly fine. I was thinking of getting one of those new fangled flat screen ones too. I could also do with a flatscreen as a second monitor. When I used the old one I was reminded of how small the screen is and how big and heavy the monitor itself actually is!! If your white silicone is 100% silicone that would work too. But if it isn't arcing it doesn't need more cleaning or silicone. The damage is done and you probably need a focus divider or whatever on your particular set provides the focus grid inside the CRT with voltage. I think when it I first switch it on it may be arcing and hissing a little, it was not like the arcing which I had before I cleaned it (or cleaned a smaller area) where you could see a fairly distinctive arc, but rather more of a sort of 'glow' over the top of part of the tube. There was an area which was sort of 'illuminated). Actualy it may have been several 'mini-arcs' certainlty the curve of the tube would make a straight one impossible, maybe if I clean it better, it will help. Hmmm cleaned it a lot more but it's hard to get at a lot of it. Still blurred when I switched on, then after a while the picture started narrowing (going widescreen so to speak!!). What would cause that? Anyway I switched it off again and had another go at drying it, put it back on and it was back to full screen and not as blured, it was soon back to unblurred, but it had had a bit of a 'warm up' from earlier. Picture is good now ie full screen and sharp, I don't think it will 'collapse in' again. I will see what it is like when it has been off over night to access what difference it made. When electronic things get better as they warm it's usually associated with tubes or electrolytic capacitors. Since your TV has only one tube the CRT, it's plausible that it's at fault where focus is concerned. When you first posted your chief complaint was that it took 15 minutes to focus but only after you cleaned the anode cap. How was it before it started hissing? There was no noticiable delay, by the time the picture was visable it was in focus. I am not 100% clear about things but I think maybe that the tape fixed it at first but the next day when I switched on it hissed, I am not sure if it was also blurred, my post seems to indicated it was only blurred after cleaning. However I am not 100% sure of this. I don't see a decent correlation between events here. Some may be coincidental. I don't remember the age or brand of TV either. Was that ever mentioned? TV is about 5 years old. It's a Wharfdale :O) Disturbingly similar to this one http://www.unbeatable.co.uk/product/.../28143603.html Wharfedale CTV2185RF Comes with years guarantee, which is less that you are entitled to under the law of the land - lol. There may be a problem in that if theTV is 'warmed up' doing something to it like cleaninh may not 'take-effect' blurring wise untill the next day. Incidently I had this problem befo- http://groups.google.co.uk/group/sci...pint&lnk=ol & (im half_pint there). Incidently the set did eventually go completely, but I the problem was cured in the meantime, then one day when, I switched on it just 'went', ie went dead, no fireworks that I could see, just the normal click when you switch on then nothing. It worked for a while before it went, but not that long because I have had this one for a while, I also got a portable as a back-up :O). I also have a USB TV stick I can use. I will read up on this flyback stuff to see if I can make sense of it, It might help me understand what is going on. I am wondering if putting the back back on the TV will help things? I won't know untill the TV has been swiched off for a long time. I guess LCD TV's don't have this problem? TV is find at the moment, good picture. I will time the warm up next time it has been off over night. You should wait a day after you clean it to power it up. Especially if you use a water based cleaner. And while it's sizzling it probably will effect the focus. I actually tried white spirit first (alcohol) but I don't think it was that good so I used just water next, maybe with some washing up liquid in it. I know tobacco smoke deposits seem to be very water soluble. Water is a good solvent. Some tars won't dissolve in ethyl alcohol but most will in isopropyl or methyl alcohol. Personally I would have started with testing a small area using a dab of Acetone on a rag. If the surface seemed to tolerate that well then I would have wiped around the anode cap for maybe 50 millimeters then the cap itself provided it too was silicone rubber as Acetone doesn't react with 100% silicone rubber readily. Well...switched on this morning and.... no blurry picture!!! However it was hissing a bit, I can't see no arcing however it's hard to see with the back on, the hissing seems to have stopped now. I thought putting the back on would help, I think the same happened with my last TV but I can' remember clearly. It seems to me it is effecting the capacitance in some way or whatever. I an not sure about all this flyback stuuf and how it works and why the tube is involved. Is the tube used as a smoothing capacitor? Regarding solvents I know water works because I have to clean up smoke deposits else where and I just use water and maybe some detergent., with white spirist everything smells of alcohol. Well I can't remember when reinstalling a TV back sharpened up a focus problem but I guess I've not seen every little oddity. Well all the evidence I have seen is that it does!! It was fine this morning, it hiss a bit but that has dissapeared totally. I am tempted to take the back off again and see what it is like when it fires up in the morning, however I don't think I have done my back any favours lugging it up and down from it's normal resting spot. I can perhaps see why it would cause a difference to the capacitive characteristics of the tube, particularly if the back is covered in smoke deposits. I have a feeling I had the same with the old set, that is why I mentioned it before I tried it I think. |
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Hissing TV.
"Meat Plow" wrote in message ... On Wed, 4 Nov 2009 01:33:55 -0000, "Colin Trunt" wrote: snip for brevity Well...switched on this morning and.... no blurry picture!!! However it was hissing a bit, I can't see no arcing however it's hard to see with the back on, the hissing seems to have stopped now. I thought putting the back on would help, I think the same happened with my last TV but I can' remember clearly. It seems to me it is effecting the capacitance in some way or whatever. I an not sure about all this flyback stuuf and how it works and why the tube is involved. Is the tube used as a smoothing capacitor? Regarding solvents I know water works because I have to clean up smoke deposits else where and I just use water and maybe some detergent., with white spirist everything smells of alcohol. Well I can't remember when reinstalling a TV back sharpened up a focus problem but I guess I've not seen every little oddity. Well all the evidence I have seen is that it does!! It was fine this morning, it hiss a bit but that has dissapeared totally. I am tempted to take the back off again and see what it is like when it fires up in the morning, however I don't think I have done my back any favours lugging it up and down from it's normal resting spot. Well maybe in the name of closure but I think it's best to leave sleeping dogs lie. I can perhaps see why it would cause a difference to the capacitive characteristics of the tube, particularly if the back is covered in smoke deposits. I have a feeling I had the same with the old set, that is why I mentioned it before I tried it I think. If I recall the focus grid on a larger CRT is upawards of 200 volts. It's just hard for me to vision the back of your tv effects the focus, And I've seen some focus adjustments that were not accesable unless the back was removed. Oh at least you've got a watchable set for now. Very true, there is certainly no focus adjustment visable with the cover on. Maybe I will give it a test some time but I will leave it for the moment. |
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