Tools: Electric soldering iron (20W-30W), solder wire, and rosin water (buy some rosin and soak it in alcohol). The soldering iron, solder wire, and rosin are available in the electronics market. You can buy a small bottle of alcohol in the drug store. Find a small bottle with a lid, fill it with alcohol and relax the fragrance appropriately. You have to try the concentration yourself.

Note: The soldering iron is easy to burn (that is, the soldering iron tip is oxidized and cannot stick to the tin), so the soldering iron cannot be turned on all the time. This is the most common mistake for beginners. You must control the temperature (of course it is best I need to buy an automatic temperature-controlled soldering iron, which only costs thirty or forty yuan).

It’s hard to say about the wiring problem, and the specific situation will be dealt with on a case-by-case basis.