With the development of the economy, the people's requirements for long range communication have increased, and DMR radios have gradually begun to be used in public fields such as taxi dispatching, security, property management services, construction sites, hotels and restaurants. So how many kilometers can the longest call distance of a DMR radio reach? In an ideal situation (without any obstruct...
The critical value of 0.5W is defined because in the field of amateur radio communications, it is generally believed that equipment below 0.5W has low output power, limited use distance, and is unlikely to cause interference to other equipment or radio and television. Therefore, these low-power devices are generally considered not to require approval and authorization, such as some small radio tra...
"I'm in junior high school now. I love radio. I also learned some amateur radio knowledge by myself. I often communicate with my friends using FRS walkie-talkies. Can I get a radio license?" A seemingly simple question, but also asked a lot of HAM. 1. Can children take the radio station operator's license test? In China，there is no age limit for participating in Class A and Class B operational tec...
Dual standby: Dual band radios generally display two lines up and down, which are generally called the main channel and the secondary channel. When there is no signal coming, the main channel and the secondary channel are in standby mode. When there is a signal coming in, the walkie-talkie will choose the signal that comes first. When there is already a signal coming in, another signal cannot come...
Walkie-talkies are commonly used in underground parking lots in residential areas, shopping malls, and hotels. However, communication signals can be weak due to the underground location, which affects communication. How can we enhance the signal when using a walkie-talkie in an underground parking lot? In general, the reinforced concrete walls in the basement of residential buildings are quite thi...
The role of the repeater in two-way radios is to increase the communication distance of the radios. When the distance between two radios exceeds the range of the radio signal, the radio will not receive an effective signal, requiring the use of a repeater. The repeater, also known as a relay station or forwarding station, is an essential equipment in the field of specialized mobile communication. ...
Have you ever thought about receiving pictures sent from the International Space Station to Earth? Actually, all you need is a simple handheld radio and your mobile phone to make it happen! The International Space Station (ISS) holds an annual Slow-Scan Television (SSTV) event where images are transmitted to Earth. SSTV is a primary method used by amateur radio enthusiasts to transmit pictures. In...
In today's society, where electronic devices such as smartphones and computers are increasingly prevalent, charging efficiency is becoming a crucial issue. Few people can resist the efficiency of "five minutes of charging for two hours of talk time," and walkie-talkies are no exception. Compared to traditional charging methods, two-way radios with Type-C interfaces have obvious advantages. Not onl...
