Walkie-talkies communicate with each other by radio signals. Different from wired communication, background noise will inevitably appear in radio communication. This kind of noise is tiresome and causes auditory interference and fatigue to users. The purpose of setting the squelch level is to control the influence of back noise.
Although the squelch level setting of different radio is not the same, the larger the number, and the higher the level. The smaller the interference of noise or other irrelevant signals, the smaller the noise, but also the less likely it is to receive the useful weak signal that needs to be received. Conversely, the smaller the number, the lower the level and the lower the level, the stronger the suppression of noise suppression, the greater the interference from noise and other useless signals, and the easier it is to receive weak useful signals. The "0" level indicates that there is no squelch suppression function, which is the lowest level.
To adjust the squelch is to reduce, suppress or eliminate useless noise so that it will not be transmitted through the speaker, but the calling message must be retained. Especially in long-distance calls, such as satellite calls and SSTV activities, weak remote communication signals are suppressed along with noise, which is also undesirable. Therefore, if we want to use the radio station Ailunce HD1 for SSTV reception activities, the squelch level can be set to level 0 to receive more effective signals.
The squelch is the basic function of the walkie-talkie. Normally, we can set the squelch of our walkie-talkie to a medium level. Then adjust the squelch level appropriately according to the back noise in a specific situation.