Simple, safe and energy-saving degaussing circuit design

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There is an article on the TV tube degaussing circuit that "degaussing function does not need to be used every time, sometimes it can be used for a long time", and it is recommended to set a manual switch for the degaussing circuit.
The author believes that due to the existence of stray magnetic fields and geomagnetic effects in the space, the color TV will suffer from the magnetic field pollution at any time and anywhere and the screen magnetization will occur. Therefore, automatic degaussing is essential, but it is necessary to improve the degaussing circuit.
Here is a very effective example of safe and energy-saving degaussing, see the picture below.
Change the AC power switch K1 to the model with the trigger sub-switch, and add a 15~60s time-release time relay Js with a load contact 5~10A.
When K1 is closed, K1a and K1b are turned on to supply power to the whole machine. Since the KIC synchronization is instantaneously closed, the Js triggers the pull-in and the contacts close. The closing of the contact Ja ensures the self-locking of the Js after the KIC is reset; the closing of the Jb supplies power to the degaussing coil L and the PTC degaussing thermistor Rt, and demagnetizes the CRT. The whole degaussing process is determined by the delay release time of Js. When the delay time is up, Js loses power, and the contacts Ja and Jb are released into a normally open state, so that Js, L and Rt are completely separated from the circuit, and the degaussing is achieved. The requirements for clearing the screen have achieved the goal of energy saving and safety.
Because only when the AC power switch is closed, K1 can perform one-time instant degaussing, and in the standby state, it can effectively refuse to repeatedly start the degaussing circuit, so it is more reasonable than the CPU-driven degaussing principle of Toshiba and Changhong.
The advantages of this circuit reform are:
1. It consumes electricity only during degaussing and saves energy.
2. After the degaussing, the PTC has no temperature rise and reduces the internal temperature.
3. Reduce the electromagnetic interference of alternating, the screen color is pure and clean.
4. After the degaussing, the degaussing components are completely separated from the circuit, which improves the safety and reliability of the whole machine.