Dear friends, what do you know about radio? It's the phone in your hand, the microphone in my hand, or the WIFI you often use to surf the internet. These are all within the scope of radio. The radio I want to talk about today is called amateur radio, which has some similarities and differences with what was mentioned above. Amateur radio refers to the radio that individuals can use, which must be approved by relevant national departments before use. At the same time, it must undergo some professional training. People engaged in this activity are called amateur radio enthusiasts, which are widely distributed around the world. They spend a lot of time and money on this hobby, and the fun is not something that outsiders can understand. They will take food and equipment in their spare time, climb a local mountain, put up an antenna to turn on the equipment, and try to communicate with the outside world, which can connect hundreds of kilometers near and tens of thousands of kilometers far away. The more radio stations you can connect with, the stronger your sense of accomplishment. In this group, the daily discussion is about how to communicate the longest distance with the lowest power, what antennas, instruments are used, and how to repair electronic circuits. If one night, after a long period of research, it connects to another radio station thousands of miles away, and the joy is like discovering the New World. In addition to these daily pleasures, an important role of amateur radio is its emergency use. One example is that during the 2008 Wenchuan earthquake, within three minutes of the earthquake, the local radio relay was already on, receiving signals from amateur radio enthusiasts in the disaster area, and then determining the location of the epicenter within more than ten minutes. In the subsequent rescue process, radio enthusiasts from various regions played a role in transmitting various information, buying valuable time for emergency rescue. I came into contact with amateur radio by chance many years ago, and then I officially obtained the certificate last year. Although this certificate does not bring me any money or other value, it is a symbol of my hobby.