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Default TV tube, hissing, fizzling crackling noise, arcing.


"James Sweet" wrote in message
news:aDVMc.28085$eM2.1834@attbi_s51...


There is like a big round 'sucker' (plunger shaped thing)
where it atttaches to the tube, this has a lot of (well a fair bit

of)
black 'dust' on. I can see some blue 'arcing' on the 'sucker type'
thing which the cable is attached too. this is where the niose comes

from.


That's fairly common, you need to remove the anode cap


How do I do that? Just pull it off?
Is it rubber or metal, I thought it was metal, maybe it
is rubber, (rubber sounds more sensible.


It's rubber,


So it *should* be safe to touch???????
The 'light show' is on the outside of this rubber cap (iits all covered
in black dust though).

I am a little puzzeled, if the tube is earthed, and the outside of the
cap is high tension.........if the two meet.....boom..(or zap).
Is this the final arc zap mentioned earlier in the thread?

And why is the outside of the cap high tension, is it because of the
black stuff or is the cap perished?


I think I assumed (wrongly) the outside of the cap was ment to be HT.

I am a little more worried now.




underneath is a metal clip that clips into a little metal pot
cast in the glass of the tube. Once you lift the edge it'll be obvious how
to remove it.





(the suction cup
thing) clean the tube well, then smear the rubber with some dielectric
grease you can get at any autoparts store. You need to discharge the

tube
first, just connect a wire to a screwdriver, and connect the other end

to
the metal ground strap around the back of the tube


I am not sure I can find an obvious ground, there is very little metal
visable.
The four corners where the tube attatches to the case seem to have wires
attatched to then, I assume these would be earth?
There is very little other metal to be seem.



The back of the tube is coated with a dark gray conductive coating, there
should be some sort of ground contact that connects to that, often there's

a
metal strap around the back of the tube.



Yes I can see a braided metal strap held round the tube by wires which
appear to connecte to the afore mentioned corners, it helped when I
used a decent light to see with.


Thanks again