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four coils are used to create a magnetic field to deflect the electron beam in two dimensions.
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How electrons move in picture tube of TV?
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.
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.
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.
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.
Do the magnets in a television make the picture?
No. Or rather, it's a lot more complicated than that. Magnets are important in a cathode ray tube style television, but they don't "make the picture". The picture shows up as a result of an electron beam hitting the phosphor-covered inside of the tube. The magnets are used to steer the electron beam. In an LCD or LED type television, there are no magnets and an entirely different process is used.
How the picture tube resistance make it possible to scan in horizontal as well as in vertical direction simultaneously?
It's nothing to do with the picture tube ! The electron beam in a CRT is manipulated both horizontally and vertically by the influence of electro-magnetism generated in the coil that surrounds the neck of the tube.
Which scientist used the cathode ray tube to isolate the electron in 1897?
J.J. Thomson used the cathode ray. Thomson's cathode ray experiment was when he shot a narrow beam of electrons through a cylindrical tube and deflected the electrons off of electric and magnetic fields, thus measuring the effects that those fields had on the direction of the beam.
What is the stream of particles originating from a cathode in a vacuum tube?
Not sure of the question, but *electrons flow from cathode to plate in a CRT. A deflection coil guides the electron beam to various areas of the screen. Some CRTs use electrostatic deflection, where the beam is deflected by four grids that steer the beam.
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
How electrons move in picture tube of TV?
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.
In the vacuum tube of the X-ray machine what is the point where the electron beam interacts with the anode called?
This point, the place where the electron beam strikes the anode, is generally called the target.
What is the evidence that an electron carries an electric charge?
the deflection of an electron beam in a cathode ray tube by electric and magnetic feilds.
Why is magnetic field used to deflect electron beam and not an electric field in a television picture tube?
if electric field is used then we have to apply a very high voltage ,or we may require a very long tube.however ,if a magnetic field is used ,even a small field can produce large deflection ,on the other hand ,the required size of the picture tube will be highly reduced .due to this reason,the magnetic field is uesd to deflect the electron beam in T.V. insted of the electric field.
How is electromagnetism used to control in beam particles?
charged particles are influenced by magnetic fields, an everyday example is the cathod ray tube used in televisions, electro-magnetic plates are placed arround the tube to deviate the electron beam emitted by the electron gun.
Why pressure is kept low in discharge tube?
In a cathode ray tube, the "cathode ray" is an electron beam that is used to paint a "picture" on the phosphor coating on the inside of the tube. (We look at the "picture" from the other side of the glass on which the coating is laid down - the outside.) An electron is a lightweight little dude. It weighs about 1/1836th as much as a single proton, so anything, any gas atoms that are in the flight path of an electron will cause it to scatter. That means we need to pump all the air out of the inside of the tube. After we remove all we can, we fire a "getter" (a chemical coated onto a small area inside the tube) which will bind any remaining gas molecules left inside the tube to complete the evacuation process. No more pesky atoms to get in the path of the electron beam and scatter it all over the place. Kwao Edward
