The mouse expeller contains a casing member, a control circuit inside the casing member, and at least a sounding device also inside the casing member and connected to the control circuit. The control circuit contains a voltage regulator IC, audio-frequency oscillator ICs, variable resistors, capacitors, transistors, resistors, and a light emitting diode (LED), a switch, and a power connector. The power connector is connected to a power adaptor. Adjusting the variable resistors is able to alter the frequencies of the audio-frequency oscillator ICs. The sounding device contains a tubular body functioning as a closed resonant chamber so as to boost the sound power to cover a large area.
