Signs a tv color tube is going bad?

Answer 1

1. The best way of testing a picture tube is by switching the TV set to an empty of channel with plenty of snow (RF noise). If you look see the snow looking sharp in the center of the screen, in the corners of the screen (this is the furthest point from the center of the screen), the snow should still look sharp. However If the snow looks blotchy on the edges of the screen you can safely say the tube is on its way out. Ps as the TV tube becomes old, it might need its refocusing control adjusted.
2. The second test is the grey scale dynamic test, the TV's black and white scale should be a constant B/W and not tinted in any way with a primary color over the broad range spectrum of the luminance. However when a CTV tube become old they do need grayscale adjustment, this should be done by competent TV technician.
3. The third test is "flaring", this occurs when the cathodes of the CTV tube are "poisoned", usually by an under driven low cathode voltage say 5.0 volts instead of 6.3 volts on the tube filament operating voltage. A quick test for "flaring; first switch on to a working TV channel, then turn up and down the brightness and contrast control. If you have "flaring", you will see yellow red flaring streaking suddenly appearing on the right side of a color TV screen projected object (usually a distinct red and white). You can revitalize a picture tube by using a B&K tube tester, by "Boosting", which cleans the cathodes of the picture. This usually gives you an excellent picture for about a week or two.
4. I have had a "man of the cloth" who put one across me when I was ordered to check out a CTV set for a Trade-In. Unbeknown to me, "the man of the cloth" had paid a repairperson to install a skillfully concealed 9.3-volt picture tube filament transformer. After the technician had readjusted the set, the "man in the cloth" rang up for a trade-in valuation. I had no picture tube analyzer (considered too expensive to purchase) and the CTV picture tube appeared okay to me. Outcome was that the dimwitted sales representative gave an overgenerous $400 valuation for the trade-in on his TV set, a make and model of which was renowned as having a bad service reputation. Furthermore, the sales representative informed me that it was none of business in the valuing of TV sets; I was only to check them. Subsequently the ctv picture tube only lasted two weeks on the showroom floor, and course it was my entire fault.
5. Therefore, to check picture tubes one should always use a B&K Tube Analyzer, tester, or something similar.