Voice-operated electronic doorbell circuit

The invention discloses a voice-operated electronic doorbell circuit. TR in the circuit is an adjustable resistor, is connected in parallel with a 220u capacitor C2 and forms a control circuit with a triode Q2 together; a triode Q3, a triode Q1, a resistor R2 and a 0.33u capacitor C1 form an oscillator; a collector of the triode Q3 is connected with a speaker; the other end of the speaker is connected with an emitter of Q1; 3V voltage is provided by a power supply; a positive electrode end of the power supply is connected with a switch S; and C3 is a 33u filtering capacitor and is connected in parallel with the power supply for use. Vibration input is realized by using the speaker; and doorbell ring output is mainly used for the electronic doorbell circuit. When a guest comes, the guest needs only to knock on a door once, and the doorbell sounds. If the sound of the doorbell is not required, the effect can be achieved by only turning off the switch.