Here the question arises - where to start?

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The master is faced with the task of identifying the malfunction and eliminating it with the least expenditure of time and effort. To do this, it is necessary to follow a certain method of finding faults.

If a workshop or a private repairman values ​​its reputation, it is necessary to start with cleaning the device. Armed with a soft brush and a vacuum cleaner, you should clean the inner surface of the case, the surface uk telegram data of the kinescope and the board of the television receiver.After thorough cleaning, an external inspection of the board and its components is performed. Sometimes, the location of the fault can be immediately determined by swollen or burst capacitors, burnt resistors, or transistors and microcircuits that have burned through. It happens that after cleaning the kinescope from dust, instead of a transparent bulb, we see a milky-white inner surface (vacuum loss).

Much more often, visual inspection does not reveal external signs of faulty parts.

It is most advisable to start repairs by checking the functionality of the power supply. To do this, disconnect the load (line scan output stage) and connect a 220 V, 60…100 W incandescent lamp instead.

Typically, the line scan supply voltage is 110...150 V depending on the size of the kinescope. Having examined the secondary circuits, on the board next to the pulse transformer of the power supply we find the filter capacitor, which most often has a capacity of 47...100 μF and an operating voltage of about 160 V. Next to the filter is a rectifier of the line scan supply voltage. After the filter, the voltage goes to the output stage through a choke, a limiting resistor or a fuse, and sometimes there is just a jumper on the board. By unsoldering this element, we disconnect the output stage of the power supply from the line scan stage. In parallel to the capacitor, we connect an incandescent lamp - a load simulator.