Basically, broadcasting static during a call on is a sign of the fact that signal strength is degrading (or that there is no signal coming through whatsoever). When signal strength degrades sufficiently, the static resonance emerges.
When there’s no communication coming through, it is a slightly different narrative. A 2 way radio has what’s known as a ‘squelch’ regulate circuit that maintains tabs on the signal strength. The squelch circuit will quiet the speaker when it realizes that there is no signal coming through to the device. That is, basically, a similar purpose as your TV has as soon as it cuts off an unavailable station after a preset time. Though, in the moments before your walkie talkie ‘squelches’ the sound, you’ll hear static, or ‘white noise’ as it’s also called. Continue reading