Q: What walkie talkie should I buy for hiking and mountain climbing?
A: First, you should have at least one national unlicensed interphone (409mhz, 0.5W transmitting power, 20 channels), the city's connectivity distance is about 500 meters, and the suburbs can reach one to three kilometers for entry-level use. Then, you can consider licensing, using handbenches and platforms in spare time (430-440mhz, and mill / green field frequency points are also in this range).
Q: Can you buy a model that takes into account 409m and spare time segment in one step?
A: Yes, but don't buy brands or models with unstable performance. After all, outdoor sports require communication: reliable. In addition, these models may not pass the inspection without the Commission.
Q: How much distance is the corresponding call distance for 0.5w/2w/4w?
A: There are many factors determining the distance of connection, and the height, antenna and terrain all influence the distance more than power, so the power and the call distance have not one-to-one correspondence. Different brands of design, technology, component quality, also affect the power play. Q: What is the specification for using interphone to talk?
A: In the spare time, there are very strict rules of association, and special training will be provided when the license is tested. In the case of license free 409m, the following provisions are provided:
*The transmission frequency shall not be changed, the transmission power shall be increased (including additional RF power amplifier) and the antenna shall not be connected outside or other transmitting antenna shall be used without authorization;
*Harmful interference shall not be generated to various legitimate radio services during use. Once harmful interference is found, it shall be stopped immediately and measures shall be taken to eliminate interference before it can be used;
*When public interphone is used, its communication quality shall not be protected by radio management organization, and shall bear the interference that may be caused by other normal radio services;
*It is forbidden to use at airports and aircraft;
*It is prohibited to connect with public network, public mobile communication network and other telecommunication networks.
Q: What is the consequence of using amateur segments without a license (e.g. mill / green field frequency point)?
A: Technically speaking, using spare time without enough knowledge will cause interference and ignorance to others. Legally, equipment and fines may be confiscated and those with serious consequences (which may have been caused completely without your own knowledge) can be sentenced to fixed-term imprisonment of not more than three years. If it is in violation of national security law at the same time, it will be even more serious.
And in the amateur section, if you don't have a legal call, no one will take care of you, because the licensed ham and unlicensed Union will be revoked. Q: Some water and cargo walkie talkies indicate that frs/gmrs are license free band. Can they be used in China?
A: Frs/gmrs is a license free band in some foreign regions, but the frequency band (462-467mhz) has been classified as other special purposes in China. So you launch at this frequency point, and you have interfered with the legitimate use of others. We do not want to do anything to others. Since we don't want others to interfere with our communication, we should not interfere with other people's normal communication.
Q: What is dumb audio? What's the usage?
A: In the spare time section, the function is mainly used for communication with relay station. In the license free 409m, mute audio is almost useless. If your walkie talkie has this function, make sure to set it to "0". Otherwise, it will be very bad for rescue to have someone else receive you and you can't hear from others.
This function was originally used in a noisy channel, both parties can agree to use the same mute audio, so that when the transmitter talks, the machine will automatically add an audio in the radio wave, and the receiver will play the signal with the agreed audio, while shielding other signals without the audio. The problem is that when your walkie talkie doesn't have a sound, it doesn't mean that the channel is idle, maybe someone else is connecting. You can't hear it because you add dumb audio. If you launch it, you interfere with other people's communication. So we joked that it was a "selfish" function.
Q: How to use walkie talkie to call for help in case of emergency?
A: Amateur section shall call relay station and maritime SOS channel within 300km in order of distance, and then operate according to the standard, and no more details shall be given. For 409m, the following steps shall be followed:
First, collect some cell phone batteries for backup, so that there is a backup battery after the intercom battery is used up. It's very easy to refit, just two wires. Only two walkie talkies are left in the power on state in the whole team, and all others are closed to save the battery.
Find two physically competent and clear minded players and take two walkie talkies to the nearby Zui high point (the higher the better, but pay attention to their own safety). One walkie talkie is on channel 15 to listen (make sure to turn off mute function!), and the other calls from channel 1 to channel 20: "sossos here is xx/xxx in an emergency call for help in a mountain. Here is xx/xxx in a mountain for emergency call. Please receive the signal and reply to channel 15. Please reply to channel 15 when receiving the signal". After ten minutes after the completion of a round of calls, the next round of call will be carried out call. If there is no reply in an hour, you can consider moving to a higher and wider position. During the movement, keep listening to channel 15. On the top of the mountain without shelter, it is possible to send out signals from 0.5W walkie talkie to hundreds of kilometers.
Q: How to deal with the call for help signal received on the interphone?
A: The following are the following: to ensure the safety of themselves and the team in sequence; secondly, inform the whole team to abandon the original plan and take saving the people as the objective; thirdly, establish with the outside world and forward the signal of seeking for help to serve as the communication bridge between the rescuer and the outside world; fourthly, rescue the rescue in the circumstances within its ability. The third point is very important. If the signal of the call for help has not been forwarded to the outside world, do not take any action.
Q: Is the headset easy to use? Is vox functional useful?
A: Headphones are not suitable for large body movement, which can easily cause headphones to fall off and they don't know, so they delay contact. For the sports that need to liberate both hands, such as road cycling and paraglider, earphone can be used, but the habit of checking headphones at any time must be developed. If you must use headphones, let friends who understand the electronics modify the headphone jack, so that the headphones and speakers can sound simultaneously, reducing the possibility that the headset will not hear the call due to the headphone falling off.
Vox can judge the strength and strength of surrounding sound through microphone level, and automatically launch when you speak without pressing the launch button by hand. This function is very unreliable in noisy and multi-human environment, which causes it is often in the emission state and has no idea of it. It costs electricity and disturb others. Therefore, it is recommended that vox functions should not be used.
