How to demagnetize a TV screen at home

Despite the availability of a huge selection of modern LSD and plasma screens, there are people who still use old CRT televisions and monitors. And very often they encounter various problems. One of them is the appearance of various multi-colored and dark spots on the screen. This problem is caused by magnetization of the screen. And many begin to think that the TV or monitor has completely failed. However, this is a fairly easily solvable problem. You just need to demagnetize the shadow mask of the kinescope.

Reasons for screen magnetization

The shadow mask is a structural element of a cathode ray tube.

ATTENTION! The mask is responsible for the projection of red, blue and green electronic colors onto the CRT phosphor.

To avoid magnetization of the kinescope, televisions and monitors are equipped with a posistor and a demagnetization coil. They only work when the device is turned off. If the kinescope is magnetized, this does not always mean that the posistor or coil has failed.

There may be several reasons for the occurrence of such a problem - both external and internal.

These include:

1. Failure of one or more elements of the installed demagnetization system. This reason is the most common.
2. Frequently turning on and off the TV with a minimum interval of time.
3. Electronic devices located at a short distance that create an electromagnetic field. This could be cell phones, speaker systems, radios and other household appliances.

The standard demagnetization loop rarely fails. Usually it is the posistor that causes the malfunction. Failure of this element very often occurs due to improper operation of the devices. Turning off the TV not using a special button on the remote control, but unplugging the plug from the network, causes a short-term surge of large current. Due to such a shock, posistors fail. The opposite situation also happens when the devices are not disconnected from the 220 network at all, which leads to their gradual magnetization and the appearance of color distortions on the kinescope.

If such a problem arises, you should not immediately contact a workshop, since you can deal with it yourself at home.

How to demagnetize a TV at home

There are two ways to deal with a magnetized picture tube:

1. If the distortion area is small, then a standard system can help cope. The device must be turned off for about 30 minutes. If there is less distortion, then the procedure must be carried out several times until they disappear completely.
2. The second way is to use a special throttle. Now it is quite problematic to find it even in stores. However, it is not difficult to make it yourself.

How to make a choke for demagnetizing picture tubes? To do this you need the following:

• mandrel;
• PEL cord - 2;
• insulating tape;
• any button;
• cord for 220 V network.

The cord is wound around the mandrel; you need to make about 850 revolutions. After which it must be insulated with tape. An on/off button is attached to the resulting structure and the power cord is supplied.

Demagnetization stages:

1. We heat the TV picture tube for a short time.
2. We supply power to the demagnetization device. From a distance of at least two meters from the screen, we begin to make wide rotational movements.
3. We gradually approach the kinescope, gradually making the radius of rotation smaller.
4. Once the choke is in close proximity to the picture tube, the distortion will increase. There is no need to be afraid.
5. Without stopping the circular movements, you also need to slowly step back and turn off the device.
6. If the distortion does not disappear immediately, the procedure should be repeated.

The throttle cannot be kept on for a long time. This causes it to heat up. The entire procedure must be carried out fairly quickly. This should take approximately 30 seconds.

IMPORTANT! It is strictly forbidden to use a permanent magnet!

It happens that both of these options do not help. This means that the posistor has failed and needs to be replaced with a similar one.

To avoid re-magnetization, you should remember that the TV must be turned off correctly and allowed to rest for a while.