0.5 watts of power can cover tens of thousands of kilometers? What are radio enthusiasts doing?

For most people, radio must be a very distant thing. We have almost only seen it in movies or games. In games like Mystic Call and Battlefield series, there are scenes of using radio to coordinate troops and call for support. As a means of communication in the pre-Internet era. It is common in military, public safety, emergency, commercial and other special communication purposes. But guess how many amateur radio enthusiasts there are in the United States in 2024? According to the American Radio Relay League, there are about 700,000 Hams in the U.S. and about 3 million worldwide.

So I am very curious, why are there so many people playing radio today when the Internet is so developed? So I shamelessly sent a private message to Tim, a senior amateur radio enthusiast. I want to know how to play radio. Tim happened to tell me that in two days, it will be the 2024 Jarbalo Amateur Radio Association
. At that time, many enthusiasts will be at the annual meeting in Chengdu. It is better to hit the day than to choose a day, so we just go straight to Jarbalo to feel what amateur radio enthusiasts are playing on the spot.

Amateur radio enthusiasts, also known as Ham, refer to a group of people who use radio stations and other wireless equipment to conduct non-commercial communications around the world. When I didn't know much about radio, my first question should be the same as everyone else's, that is, why is it called amateur radio? Later, after reading the information, I learned that this amateur does not mean amateur ability and level. It means non-professional and non-commercial. Corresponding to this are special frequency bands such as military defense public broadcasting, aviation and maritime commercial communications. The radio spectrum is an important strategic scarce resource for the country. And it is an extremely complex system. my country's radio frequency division map looks like this. These dense colors represent different uses in different frequency bands. In order not to cause interference to other frequency bands, the state has specially divided frequency bands for amateur radio enthusiasts. In these allowed frequency bands, HAM can communicate freely.

In fact, the Jarbalo Amateur Radio Association I participated in this time is more like a carnival for enthusiasts. There are booths for various equipment, Ham's own equipment for communication, and radio imaging and communication competitions. When I first arrived at the event, the first thing that attracted me was actually the cars of radio enthusiasts. Regardless of the brand or model, almost every car here is equipped with a car radio. And there are conspicuous antennas on the body. I guess this group has a high overlap with fishing guys and outdoor enthusiasts. But compared with other niche hobbies, amateur radio still has a certain threshold. First of all, if you want to become a Ham in China, you need an amateur radio operation certificate. It is divided into three categories: a, b, and c, with category c being the highest. A category a operation certificate can operate the remaining high frequency and ultra-high frequency bands, and the maximum power does not exceed 25 watts, so the communication distance is not very far. Generally only a few kilometers to tens of kilometers. A category b operation certificate can be used including shortwave, very high frequency and ultra-high frequency, etc., with a wider coverage and a maximum power of no more than 100 watts. The communication distance can be from hundreds of kilometers to thousands of kilometers, and even across the communication intensity. The C operator license is the highest operating authority, allowing the same frequency as Class B. However, the maximum power allowed is 1 kilowatt. In theory, you can communicate with HAMs in any country in the world. Of course, if you can use some special techniques, such as satellite Class A, you can also communicate with the world. However, Class C cannot be taken directly. You have to pass the Class A test. You can only take the Class B operator license after setting up the station for 6 months. Then get a shortwave license. You also need another thing called a radio station license. It is equivalent to passing the driver's license test and having your own car, and you still need a driving license. At this time, you will get a unique symbol. So we see on the sign-in board that everyone signs their own symbol. At this step, congratulations, you are already a fresh ham. Next, you only need to spend a few years to learn some knowledge of physics, geography, foreign languages, circuit foundations, communication engineering, signal processing, computer science, etc. Then communicate with hundreds of people around the world, and you can almost become an old ham.

As a ham who has not yet entered the field, the second question is: What do you do in the world of radio? So I asked around at the scene and found that everyone's playing content is really different. Some people play short broadcasts to communicate with enthusiasts from all over the world, some like to participate in various radio competitions, some like to design and build radio antenna feed systems, and some are keen on playing satellite communications. There are also many DIY enthusiasts who regard tinkering with equipment as the greatest pleasure. We also asked a brother who was challenging 0.5 watts of power to make ultra-long-distance communications. And he has already communicated with dozens of countries. He is playing with the customer source RP low power. Playing with low power is actually more of a challenge and excitement. And this, uh, you can learn a lot of knowledge about astronomy and geography, because this kind of low power is completely based on your talent, and the reflection and refraction of the ionosphere. In this case, you need to see at different times that his ionosphere can just reflect such a small power. To reach the farthest distance. The brother also told me that the fun of low power is also DIY. He carried six sets of CW Morsma kits made by enthusiasts. When the antenna feed system is well matched and the ionospheric propagation is very powerful, such a low-power kit can send signals over tens of thousands of kilometers. Because there are many types of people who are good at radio signals. One type is simply those who like the UV of this handheld radio, and some like the short broadcast. There is also a part that likes the WeChat WeChat communication, and there is also a part that likes to collect cards as you just said. So we have a basis for collecting cards, that is, you have to play short broadcast. Because you can communicate far enough, to people from all over the world, so that you can exchange more cards. The QSL card mentioned by Tim just now is a proof that Hams have communicated with each other. As early as the 1920s, it was popular among radio enthusiasts. After the radio enthusiasts communicated, they would mail each other a QSL card, which was also a way to exchange contact information. This card has the call sign of the other party, the communication time, and geographical information. Some Hams will also stamp their own seals. The back is where the radio enthusiasts can show their creativity. Many wireless enthusiasts will pursue collecting as many QSL cards as possible. Just like completing achievements in games. As the times progress, many Hams will give each other a QSL card to commemorate the exchange.

Tim also taught me some rules that must be followed in the radio. For example, you cannot advertise, mainly to prevent people from turning on the radio and hearing all the news about recycling used cars. Wouldn't that delay everyone's communication? So the first rule is that no commercial advertisements are allowed. In addition, music and broadcasts are not allowed. These contents will also occupy frequency resources and interfere with the normal communication of other users. Another thing is to avoid occupying the frequency for a long time, especially when the frequency band is crowded, so that other enthusiasts can also have the opportunity to use the frequency, and don't insert your own call when others are powered on. Generally, you have to wait until the other party calls alternately or pauses for a short time before politely joining in. In addition, radio enthusiasts often face a small problem, that is, they are often regarded as walking money by the public. That afternoon, an amateur wireless person's image measurement competition was also held on the scene. The contestants had to find the nearby signal source through the antenna in their hands within a limited time. The closer to the signal source, the higher the frequency of the signal strength. Finally, the signal source was found and the competition was completed by punching in. It was a bit like another form of treasure hunt. And I was surprised to find that almost all the participants in this activity were middle school students. Many of them are classmates who came here in groups. Among amateur unlimited enthusiasts, the proportion of middle-aged people is relatively higher. Young people definitely like the Internet more, so it is a great fortune to have a group of like-minded peers.

When I first heard about the meaningful radio enthusiasts group. What I wanted to ask most was why there are still people playing with radio when the mobile network is so developed now.What is the use of it? And at this radio enthusiasts gathering, I finally understood its true meaning. Because I have seen a word countless times, emergency communication. After the September 11 attacks, the communication was interrupted. A group of HAMs stood up and formed a temporary communication channel. The first message sent out was sent through the radio station. If we develop more amateur radio enthusiasts, there will be more points for emergency communication. When a disaster occurs, the mountains collapse and the buildings tilt in an instant, the computer network will be interrupted, the mobile phone signal will disappear, and only the radio waves will never disappear. For individuals, the fun of radio is the meaning of its existence. I suddenly felt that I should not ask what the use of radio is. Even if all the useful attributes of radio are put aside and it is only used as a toy for enthusiasts, it naturally has its meaning.Just like we don’t ask why fishermen don’t go to the supermarket to buy fish, why camping enthusiasts don’t stay in hotels, then there is naturally no reason to ask: the meaning of radio.
He has a hobby of learning while playing, and learning while playing. And there are many things to learn, useful and useless. For example: geography, astronomy, physics and many more. As you play, you will learn more and more. The more you learn, the more ways you can play. Then the fun will be doubled. It is to be able to communicate with people all over the country and even all over the world. There is also a second situation, that is, you can also contribute in an emergency.

But I have to say that this event had the fewest people playing with mobile phones. Everyone seemed to be immersed in a world that belonged to radio. I was also infected by this atmosphere. When my child grows up a little bit, maybe I will take him to play radio. But before that, I decided to pass the Class A operator exam first. I hope this article can give you a simple understanding of radio. If this niche hobby can arouse your interest to some extent, you are also welcome to join Ham.