A self-contained Doppler demonstration comprised of an enclosure (20) with a tether attachment site (4). The enclosure (20) contains an electrical power source (12), a power source connector (13), a switch (8), and an auditory tone generator (11). In operation, the switch (8) is closed, and the demonstrator is rotated on a tether to produce the observed change in auditory pitch/frequency that is the Doppler effect.