On Mon, 24 May 2004 14:49:07 -0400, Dave Hall wrote:

Superfluous on CB. Especially on AM, where a very distinct carrier
dropping, signals the end of transmission.

nonsense,roger beeps or actually nasa beeps were used on the apollo missions.
after the moon missions is when they started catching on with cb'ers. apollo
used am radios. was nasa using the beep as a sound effect to entertain us?