First, look, with a high magnifying glass magnification, carefully check the bottom of the circuit board, especially to check the power of large heat-emitting components, such as high power resistors, three-terminal regulator, transistor, chip, power supply pin of the manifold And the output pin of the field block, the deflection coil lead-out pin header, and so on, most of the faults can be solved by repair welding.
The second is knocking. After powering on, you can use a wooden stick to gently tap each circuit board and plug-in box. When you click on the image, if there is reflection, you can roughly determine whether it is a power board, a scanning board or a signal board, or Plug-in box failure.
The third is shaking, after confirming that there is a problem with a circuit board, you can gently shake each component with a wooden stick after starting up, and you can quickly find out which component is loose.
If the above three methods are not effective, then only to find the circuit diagram of the aircraft, take a moment, carefully check the DC potential of each channel against the circuit diagram to determine the problem, which will rely on the accumulation of normal experience .
Pseudo Soldering can be directly determined visually, found that the original pin is obviously not connected with the pad, it is called Pseudo Soldering; found that the original and the pad is in good connection but is not actually connected, it is called False Soldering. Fake Soldering is more difficult to determine than Pseudo Soldering