How to improve the communication distance of walkie talkies? The following suggestions are arranged based on convenience and cost of use
- Increase launch altitude:
There is a saying circulating in the circle of amateur radio enthusiasts: “Height determines everything!” Practice has proven this to be a truth. The principle is very complex, and we will not elaborate on it here. When buying handheld walkie talkie , everyone sees this indicator: communication distance of 3-xx kilometers, which refers to the communication distance in open ground areas. And what would happen if you stood on the mountaintop with a handheld platform? The fact is that you can still connect with friends from another high-rise building!
- Choose communication environment and direction:
Choosing the communication environment and direction is important, as it can sometimes lead to significant differences in connectivity quality. Generally, we should follow the following principles:
A. Try to choose a higher terrain for connectivity, such as if you can connect on the second floor, not on the first floor.
B. Try to choose outdoor communication as the building walls have strong reflection and attenuation of 70 centimeter waves.
C. Try to avoid residential areas surrounded by buildings, densely packed buildings in the old city area, areas with dense trees, under high-rise buildings, road sections surrounded by large cars, tunnels and bridges, and large metal billboards in front of you.
D. Utilizing urban canyons: This is very important. In our big cities, there are numerous tall buildings and dense buildings, making it difficult to find real opportunities for line of sight transmission. Therefore, we need to make good use of the existing environment. The so-called urban canyon refers to the dense and tall buildings on both sides, as well as the wide and winding main roads. Even if connected on the same route as its intersection (such as vertical or diagonal sections), the connectivity effect is generally good. On the contrary, if both parties are in a complex path or building complex, the connectivity effect will be very poor. Therefore, we propose that if you are planning to connect while driving, please start after entering the wide road.
E. Choose the correct direction and avoid the obstruction of tall buildings and metal structures as much as possible between the points connected to you. If you place it behind your connecting direction, it can also serve as a signal reflector.
F. Nighttime connectivity is more effective than daytime connectivity.
G. Fixed point connectivity is more effective than mobile connectivity.
- Improve receiving sensitivity:
I don’t think I need to explain this further. If both parties increase the receiving sensitivity, it is equivalent to increasing the transmission power for the other party. Please don’t tell me that you don’t know how to adjust the receiver sensitivity of the radio station, as this is included in the manual.
- Using high gain transmitting antennas:
The efficiency of antennas is represented by gain, and different types of antennas have different gains. Generally speaking, specialized extended handheld antennas (commonly known as small whip antennas) are better than the original handheld antenna (gain of approximately 2.15DBi), car mounted antennas are better than small whip antennas (gain of 5.5-6.5DBi), pole mounted antennas are better than car mounted antennas (gain of 6.5-12DBi), and multi unit unidirectional antennas (such as Yagi antennas, logarithmic periodic antennas, circular antennas, etc.) are better than pole mounted antennas (gain of 9-24DBi).
It is strongly recommended that friends who are connected in the car use a car antenna. Keep in mind that every 3DBi gain is equivalent to doubling the transmission power of your radio station. At the same time, it avoids signal shielding of your handheld device inside the car and radiation to the human body inside the car.
Students who set up a station at home recommend using a rod antenna, which has high gain, high strength, and is easy to install. With the installation height on the rooftop, it is not a problem to cover the entire city, and some can be connected to other cities.
- Increase transmission power
Some students can’t help but ask: When I bought my handheld walkie talkie, the power was already set. How can I increase the power? In fact, there are still ways:
A. The transmission power of handheld walkie talkies is related to the voltage and capacity of the battery. When fully charged, the transmission power is higher, and vice versa. And most of the time our handheld walkie talkies work in a low battery state, so we recommend using lithium batteries that can be charged at any time to ensure maximum transmission power.
B. Some models of handheld walkie talkies can set their own transmission power (such as the Lingtong 6288), and can set a transmission power higher than 5W.
C. Some radio stations can use external power sources (nickel hydrogen batteries) to ensure maximum transmission power of handheld walkie talkies.
If the input voltage of the external power supply is increased (higher than the nominal battery voltage but lower than 13.8 volts), it can increase the nominal transmission power of the handheld walkie talkie. For example, the Beifeng 71-B can output nearly 5W of transmission power under a voltage of 12V-13.5V. But it is recommended that students use this method with caution. If the call time is too long or there are no appropriate heat dissipation measures, it is easy to burn out the amplifier module.
- Using relay stations for transfer:
The so-called relay station is a type of relay station set up at a high altitude, which uses uplink frequency to receive radio signals with varying strengths at scattered points and converts them into downlink frequency equal power transmission. It can be composed of two radio stations, one power supply, and corresponding control conversion circuits. The armed police, public security, transportation and other departments use this type of relay station to ensure that users have no blind spots and high-quality communication.
