Selection and replacement of inductors

　　 When choosing an inductor, first consider whether its performance parameters (such as inductance, rated current, quality factor, etc.) and dimensions can meet the requirements.

Small fixed inductors, color code inductors, and color ring inductors only need to have the same inductance, rated current, and similar dimensions, which can be directly substituted.

　　The oscillating coils in semiconductor radios have different models, but they can be replaced with each other as long as their inductance, quality factor, and frequency range are the same. For example, the oscillation coil LTF-1-1 can be directly replaced with LTF-3 and LTF-4.

The line oscillating coil in the TV should be the same model and specification as possible, otherwise it will affect the working state of the device and circuit.

The deflection coil is generally used in conjunction with the picture tube and line and field scanning circuits. But as long as the specifications and performance parameters are similar, even if the models are different, they can be replaced with each other.

　　2 Selection and replacement of transformer

  1. Power supply | voltage stabilizer | voltage stabilizer transformer selection and replacement

　　 When selecting a power transformer, it must match the load circuit. The power transformer should have a power margin (its output power should be slightly greater than the maximum power of the load circuit), and the output voltage should be the same as the AC input voltage of the load circuit.

　　 Ordinary power circuit, "E" type dead-heart power transformer can be used. If it is the power circuit of the high-fidelity audio power amplifier, the "C" type transformer or toroidal transformer should be selected.

　　 Regarding power transformers with the same data, output power and output voltage, they can usually be directly interchanged.

  2. Selection and Substitution of Line Output Transformer

After the line output transformer of the TV is damaged, the line output transformer of the same model as the original one should be used as much as possible. Due to different types and specifications of line output transformers, their structure, pins and secondary voltage values will be different.

When selecting a line output transformer, you should visually check whether its magnetic core is loose or broken, and whether the transformer is not tightly sealed. The output transformer of the new line should also be compared with the output transformer of the original machine line to see if the pins and internal windings can be completely different.

　 If there is no replacement of the line output transformer of the same model, the magnetic core and the output voltage phase of each winding can also be used, but the line output transformer with different pin numbers can be used for alternative replacement (for example, reversing the winding ends, changing the pin order, etc.).

　　3. Selection and replacement of intermediate frequency transformer

The intermediate frequency transformer has a fixed resonant frequency. The intermediate frequency transformer of the AM radio, the intermediate frequency transformer of the FM radio, and the intermediate frequency transformer of the TV cannot be used interchangeably, and the intermediate frequency transformer for audio production in the TV and the image intermediate frequency transformer cannot be used interchangeably. .

　　 When selecting an intermediate frequency transformer, it is best to use an intermediate frequency transformer of the same model and specification, otherwise it will be difficult to work normally. When selecting, the winding should also be stopped to check to see if there is a disconnection or short circuit (collision between the coil and the shield).

　 After an intermediate frequency transformer in the radio is damaged, if there is no replacement of the same type intermediate frequency transformer, you can only replace the complete set of intermediate frequency transformers with other types of intermediate frequency transformers (usually 3). When replacing the device, the order of a certain level of intermediate frequency transformer cannot be installed wrongly, nor can it be interchanged at will.