It's no accident that Apple chose a yellow icon for its walkie-talkie feature. I dug out my old (2002ish) Nextel with PTT (push to talk). It was all the rage back then... :
Nextel chirp - YouTube
Nextel Mobile | StartEngine
Mourning the Loss of Nextel and Its Push-to-Talk Feature for Event Staff | BizBash
Making and answering nextel walkie-talkie calls, Making nextel walkie-talkie calls | Motorola ic402 User Manual | Page 59 / 224
Speaker Microphone for the i682 Two Way Cellular Radio | Eventtone
That annoyed BEEP BEEP from NEXTEL phones in the 90s (sound in comments) : r/nostalgia
Motorola walkie talkie cellphones : r/nostalgia
nextel walkie talkie|TikTok Search
Chirp Chirp* NEXTEL | When Phones Were Fun | For a few years in America, it was tough to go a day in public without hearing a distinctive electronic “chirp.” By 2004,