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Visit：4100   Date：2019-12-26

1. Standard rules for size and thickness. Customers can measure and check the thickness and specifications of their products.
2. Light and color. The external circuit board is covered with ink, and the circuit board can play the role of insulation. If the color of the board is not bright and there is little ink, then the PCB itself is not good.
3. Weld appearance. There are many PCB parts. If the welding is not good, the parts will easily fall off, which will seriously affect the welding quality.
4. After the components are installed, the telephone should be easy to use, that is, the electrical connection must meet the requirements.
5. The line width, line thickness, and line spacing of the line meet the requirements to prevent the line from heating up, breaking, and shorting.
6, copper skin is not easy to fall off under high temperature.
7. The copper surface is not easy to oxidize, which affects the installation speed. It will be damaged soon after oxidation.
8. No additional electromagnetic radiation.
9, the shape is not deformed, so as not to deform the shell after installation, the screw holes are misaligned. Now it is all mechanized installation, the hole position of the circuit board and the deformation error of the circuit and the design should be within the allowable range.
10. High temperature, high humidity and special environment resistance should also be considered.
11. The mechanical properties of the surface must meet the installation requirements.