Beeps and melodies in two-way radio

The roger beep is a short melody sent by many hand-held radios to indicate the end of transmission. PMR also differs from ham radio in that many of its users don’t want to hear random people talking on the same frequency; indeed, many devices employ tones or digital codes designed to silence unwanted conversations, called CTCSS, DCS, or coded squelch. In this view we’ve detected roger beeps of type ‘a1’ and ‘a2’; a somewhat rare 62 Hz STE tone; and a ring tone, or alarm (RNG).

Source: www.windytan.com