Basic knowledge of communication equipment:
Wireless communication equipment, walkie-talkie is the most commonly used.
TWO WAY RADIO, it is a communication tool. If you do not need any network support, you can call, there is no phone bill, which is used to relatively fixed and frequent calls.
According to the electromagnetic theory, the lower the frequency, the longer the wavelength, the weaker the capacity of the electric wave penetration building, the stronger the diffraction capacity; the higher the frequency, the better the wavelength, the stronger the electric wave penetrates, but the resistance ability Weak. Therefore, in the city, because of high building intensity, it is necessary to avoid power, the higher the frequency, the more suitable; in the wilderness or sea, this empty geographical area is used, and the electric waves with strong diffusion capacity, so the V-segment is selected. (136-174MHz) is more suitable.
Several factors that purchase walkie-talkies need to consider:
Whether it is a hard skater, a leisure skiing, riding, etc., the walkie-talkie is a better way to keep the team. The special nature of field activities has put forward some special requirements for our purchase, and it is important to consider:
(1), power supply
Commonly used intercom supplies: lithium blunt rechargeable batteries, nickel-hydrogen rechargeable batteries, AA base cells. It is generally unable to perform charging in the wild, so the standby time and call time of the walkie-talkie is a more important parameter, otherwise it is often a problem due to the shortcomings of the intercom. In general, lithium electricity, nickel-hydrogen is relatively large, but spare batteries are a big problem; the alkali battery is generally less than 2W, but there is also a hundred No. 5 batteries.
(2), communication frequency
The relationship between communication and radio communications is like roads and cars - samples. There are two common intercom purposes now: from the abroad clips; civil society walks purchased by domestic regular stores.