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?

Reply to
Colin Trunt
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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.

Reply to
Meat Plow

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.

Reply to
Colin Trunt

"Colin Trunt" wrote in news:NC2Gm.5288$ snipped-for-privacy@newsfe20.ams:

all that tobacco smoke residue is the problem.....

just think,that gunk is all over the inside of your lungs,too.

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Jim Yanik
jyanik
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Reply to
Jim Yanik

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.

Reply to
Meat Plow

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)

Reply to
Colin Trunt

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!!

Reply to
Colin Trunt

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.

Reply to
Meat Plow

This is what 'Corona Dope' was created for.

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The movie \'Deliverance\' isn\'t a documentary!
Reply to
Michael A. Terrell

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.

Reply to
Colin Trunt

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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.

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Reply to
stratus46

Really? Gee Wiz I've never heard of that kinda Dope.

Reply to
Meat Plow

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?

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?

Reply to
Meat Plow

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

Reply to
Archon

You tried to smoke it.

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The movie \'Deliverance\' isn\'t a documentary!
Reply to
Michael A. Terrell

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.

Reply to
Meat Plow

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.

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Reply to
Colin Trunt

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.

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I was thinking plumber tape which I believe is ptfe polytetraflourotheylene or plumperstapeforelectricians. (semi joke but perhaps also true?!)

Actually reading the electrical characteristics of ptfe it sounds idea, it is a dielectric, which is what is used to seperate the plates of capacitors.

Infact if you needed to insulate someything which might becone wet it would be useful.

It is fantastic at fixing leaks anyway!! I had a leaking radiatior valve and it did a great job!!

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Reply to
Colin Trunt

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.

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Reply to
Colin Trunt

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.

TV is about 5 years old. It's a Wharfdale :O) Disturbingly similar to this one

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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 before:-

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(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.

Reply to
Colin Trunt

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