https://support.danimex.com/portal/en/kb/articles/how-does-the-dp4000-series-squelch-system-work-and-why-is-it-so-good
Description of the squelch system differences between traditional analog radios and Motorola DP4000 series radios Squelch on traditional analog radios On most...
how doesseriessquelchsystemwork
https://freesound.org/people/MrFossy/sounds/589987/
Freesound: collaborative database of creative-commons licensed sound for musicians and sound lovers. Have you freed your sound today?
freesoundsfxsquelchslayerimpulse
https://www.shure.com/en-US/insights/squelch-circuitry-technology-in-wireless-audio-systems
Squelch means "to suppress," and that's exactly what squelch circuitry does. This post discusses different types of muting circuits in wireless audio systems.
squelch circuitwireless audiotechnologysystemsshure