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They are created by the electron gun in the back, deflected by the deflection grids to move up and down and left to right, and then travel towars the front of the screen where they excite the phosphors coating the inside of the glass.
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How do you know if the TV tube is going?
Dim picture, slow to get bright and the white part of the picture turns kind of negative looking.
How can you tell if the picture tube is going dead on a 15 year old Panasonic tv?
panasonic? 15 years?,,,,,,,,,,,,, I am sure the tube is going out.
How is the electron beam in a TV picture tube deflected?
four coils are used to create a magnetic field to deflect the electron beam in two dimensions.
Can you replace a picture tube by yourself on a RCA TV?
Theoretically it is possible to change a tube on a television. However, if the question is being asked, it suggests a limited experience of television repair. Television tubes require very high voltages to operate, in the order of 20,000 volts or higher. These voltages can be lethal and they are present within a television circuit long after the television has been turned off. In addition to the danger, lining up a new tube requires detailed knowledge of the television model and the procedure to obtain a good image. Unless you are properly trained and qualified to repair televisions, do not ever remove the covers. Finally, the cost of a new tube for most televisions is now higher than a replacement television and it makes no financial sense to attempt a tube replacement. I replaced a broken Picture Tube on a RCA set myself, I got a shock while lifting the old tube into my car, I forgot to discharge the tube and lucky I didn't drop it, that would have been dangerous. I found an old used tube to replace it, a new rebuild would be too costly. I don't recommend anyone do this unless you have some knowledge.
Signs a tv color tube is going bad?
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.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.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.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.Therefore, to check picture tubes one should always use a B&K Tube Analyzer, tester, or something similar.
Why will a magnet placed in front of a tele vision picture tube distort the picture?
Moving Electrons in the TV set are deflected from their paths by magnetic fields
Why will a magnet placed in front of a tele- vision picture tube distort the picture?
Moving Electrons in the TV set are deflected from their paths by magnetic fields
Is the picture tube a conductor or an insulator Explain your answer?
A picture tube is an insulator. The electrons would gather up and so, create an electric charge when the TV is on. If it was a conductor, the charge would not build up. Hope this helps :)
Why is it necessary to connect a very high voltage at final anode of a color picture tube?
Electrons striking the phosphors at the front of the picture tube are what generate the photons our eyes see. Electrons (negatively charged) don't move unless forced to by either an electric field or a magnetic field - in this case an electric field - created by the circuitry in the TV. The distance from the back of the picture tube neck where electrons are generated (the cathode, negative charge, repels electrons) to the front of the screen where they are needed is large, perhaps 20 or 30 or more inches. Though the picture tube is evacuated, it is not a perfect vacuum and many atoms still exist inside it, which results in resistance to electron flow. Ohm's Law - Voltage = Current x Resistance - determines what happens electrically. Since the resistance of the atoms inside the tube is quite high to electrons, a high voltage is required to overcome it and force the electrons to move and strike the screen in sufficient quantity (current), after which they fall back to the metal coating inside the picture tube (the anode, positive charge, attracts electrons), completing the circuit that started at the cathode. A lower voltage will simply not provide enough force to do the job.
What are the old tv's with the big back on them?
Those were picture-tube TVs. The picture tube was almost as long as the TV screen was wide.
What is the direction of current in picture tube of TV?
A cathode ray tube (CRT) emits light when electrons strike the front of the glass tube that is covered in a phosphor coating. The front of the tube is the anode of the tube. The electrons are fired from the rear of the tube by an electrode called the cathode. The electrons are formed into a beam or ray, hence the name of cathode ray tube. Although the electrons travel from the rear of the tube to the front, or from the cathode to the anode, conventional current actually flows the opposite direction. So, the current, as measured in amps will flow from the anode to the cathode.
Can an electron at rest be set in motion by the magnetic field?
Sure. A charge in a magnetic field experiences a force. A force acting on a mass produces acceleration. Remember the old-style TV sets that were about 6 feet deep from front to back ? That type of picture tube is called a 'CRT', for "cathode-ray tube'. There's a hot wire at the back end of the picture tube that produces a cloud of electrons. The front face of the picture tube has a high positiver voltage on it, to attract the negative electrons to the front. On the way there, the electrons have to go through these magnet coils that are around the neck of the picture tube. The magnetic field inside the neck pulls the stream of electrons left and right, up and down, left and right, and that's how they draw a picture on the front face when they get there.
What is a good sentence for component?
The picture tube is the main component of a television set.The picture tube is the main component of a television set.
Does leaving a TV on in power save mode damage the picture tube?
It shouldn't. If there is no actual power to the CRT (no picture visible) then there really can't be any degradation of the tube.
How much does a picture tube cost on a tv?
A replacement tube (if it is available) is likely going to cost almost as much as the whole television. If you need a new tube, it's time to ditch the tube TV and get a flat screen.
What is monochrome TV?
Monochrome generally indicates a black and white picture.
Can a television cause an explosion?
Why not!Smashing the face of the picture tube will cause an implosion.
