Q: With the same power of 5W, why is the coverage large or small?
Just use it at your wedding. We are lovers. We got help from the relay station. You are a walkie-talkie. Explain briefly. Think of the walkie-talkie as a mobile phone. If I give you a mobile phone without a mobile phone card, you are rubbish. If I give you a mobile phone card, you can contact the whole world. The reason is the same.