Hi Peter,
Sounds like the tube is magnetised. This is usually removed by the set's automatic degaussing ciruit. Switch the set off at the mains switch (not the remote) and cycle on/off a few times, leaving it off for 1/2 hour between tries. This will operate the auto degaussing circuit every time you switch on. If this doesn't shift it , it is possible to degauss the tube manually, with a degaussing "wand"... if this then puts the set right permanently, job done. If it comes back, you probably have a faulty degaussing "thermistor" or "posistor" which is a white or black three legged device in the primary of the powersupply, just after the mains switch.It's about 15mm square for black ones and about 15mmn cylinder for the white ones. If you are confidant with a soldering iron, remove it and give it a shake, if it rattles, it's shot... obtain a new one (by the number on the top) and all should be sorted.
If you're not confidant with an iron, take it to your local friendly TV repair folks, and it shouldn't cost much to repair.
The other possibility is it has been dropped and the shadow mask in the tube has shifted... in which case it's a new tube and a big bill :(
Causes of the screen becoming magnetised include... brats with magnetic toys watching it "bend" the colours on the screen ... hifi loudspeakers too close to the screen and turning the set round or moving it (but the latter is usually cleared by the automatic degaussing circuit.)
Hope this helps,
Andy |
