Precautions for the use of vehicle antenna
Why do you say that the mobile station should not use fake antennas, because the original car station antenna can ensure that the antenna itself has a standing wave ratio below 1.5. And ensure that the impedance and reactance match. In addition to the guarantee of technical indicators, stable quality is very important. Once the antenna with unstable quality has poor contact, it may cause burn-in, and it will not be worth the loss.
Of course, when using the vehicle-mounted radio, do not deviate from the radio transmitter module and transmit at frequencies other than the center frequency of the antenna, because the more deviated, the larger the standing wave. It is also not possible to use a 400M antenna to transmit above 2 meters, and vice versa.
Before using the vehicle antenna, check the parameters of the antenna with a standing wave meter and antenna analyzer to ensure that the parameters are normal. It is difficult to ensure a good resonance point for most of the imitation antennas on the market. It is recommended to equip yourself with a standing wave meter. , Detect standing wave and power situation at any time.
Frequently check whether the feeder is damaged or not. If there is damage, it is recommended to replace it, because it will also cause radio wave leakage, forming a standing wave, and endanger the human body. If it breaks, don't launch.
The antenna can not be used upside down, the standing wave will be very large after being down, which will damage the machine.
The antenna should not be used indoors, it will cause high standing waves and be harmful to the human body.
Try not to always disassemble the antenna, it will cause poor contact over time to produce high standing waves, which will affect the life of the machine.
On rainy days, be careful not to allow water to enter the connector. If water enters, the standing wave will be high. Also pay attention to the inspection of the joints. Is there any loose condition.
The antenna feeder system is also very important. Try to use "-5" or so feeders. Most of the car machines are damaged because the feeder has a bad interface and burns.
For vehicle-mounted radios, the output voltage of the vehicle's rectifier to the battery must be below 15V. It can be measured with an electric meter. It should be noted that when the flame is turned off, the voltage is generally about 12.5V, and the voltage to be speeded should be about 13.5V. Increase the speed by 3 thousand revolutions. As long as it does not exceed 14V, the rectifier is no problem. The radio station will also be well protected.
Which parts of the car station are easily damaged?
Mechanical damage is higher than electrical damage. Most of the damage to the vehicle-mounted station is caused by bumps, such as accidentally falling on the ground and causing damage to the switch, buttons, antenna, cracking of the circuit board, damage to the display screen, etc.; or other causes caused by long-term toggle switch and antenna insertion Mechanical and electrical problems.
Transistor damage is higher than integrated circuit damage. Because the vehicle-mounted radio has a high degree of integration, there are many voltage stabilizing circuits, and the transistors are used for voltage stabilization, expansion, etc., which are often in high voltage and high current conditions, so the vehicle-mounted radios often damage the transistors. The integrated circuit is usually responsible for the effect of small signal expansion and conversion (the power expansion integrated module is outside), and has a relatively stable power supply, so the probability of damage is relatively low.
The damage of sending is higher than receiving. Because when sending a letter, especially the power expansion and control, some are often in high voltage and high current conditions, plus other factors outside the boundary, the obvious appearance is that you cannot speak.
The damage caused by misoperation is higher than the actual damage. There are some problems with the intercom of the vehicle-mounted radio because it is locked or crashed due to incorrect operation. The appearance is that the panel cannot be operated, and the receiving and sending of letters cannot be performed. The other faults only need to be operated according to the correct operation method, and the faults can be quickly removed without turning the cover.
Pay attention to the current and voltage when installing the vehicle
Generally, there are no regulations on the car’s brand for vehicle-mounted radios. Any car can be installed with any brand of vehicle-mounted radios. It should be noted that the calibration voltage of the vehicle-mounted radios is basically the same as the generator voltage of the car. For example, most of the current common cars are 13.8V DC, which can be installed on cars with a 12V power supply system (usually in cars). However, for example, the power supply voltage of a large truck is 24V, and such radio stations cannot be used directly. There are special 24V radio stations available. Or, it is necessary to use a DC-DC converter to obtain a 12V voltage for ordinary vehicle use.
At present, the commonly used VHF or UHF vehicle-mounted radio has a transmitting power of about 20 to 50W, and the power consumed from the power source when transmitting is 60 to 100W, and the power consumed when receiving is very small, at 5 to 10W, these numbers are compared to power generation The output power of the machine is relatively small and basically acceptable.
Even if it only relies on battery power after the flame is turned off, it can support a period of time (battery capacity/transmission current = approximately available time), but it is not good for the battery and should be powered by car power.