Squelch allows you to adjust sensitivity; on the receiver, it is used to eliminate background noise.

Squelch is a control often found on transceivers and is used to try to eliminate annoying environmental signals that do not allow you to receive an audio message clearly.

By raising the squelch level, it decreases the sensitivity of the receiver by eliminating background noise, but with the possibility of suppressing even weak but useful signals. Decreasing the squelch, increases the sensitivity of the receiver and we will have the opportunity to pick up even the weakest signals, but also increase the signals of disturbance.

Today many of the transceivers, including marine VHF, can be equipped with automatic squelch, which diligently adjusts the squelch appropriately, thus avoiding the user this continuous adjustment.