Mouse and Rat repellent circuit using astable multivibrator
The Mouse and Rat repellent circuit using astable multivibrator which use sound waves or ultrasonic so it escaped away. Use transistor and piezoelectric.
Sound Generator
Make Cricket Buzzer Generator circuit using LM324
The cricket sound effect circuit which is an another Sound effects generator byLM324 op-amp and emit by a buzzer. And they have sound similarly the cricket
UM3561 Sound effect generator circuits
Here is The 4 Sound effects generator using UM3561 and a few parts only. It can make siren, Ambulance sirens, Police car sirens, Fire truck siren and Space
Make Police siren Generator circuits using 555 timer
This is police siren circuit using 555 IC, with PCB layout, using 2 IC-555 as frequency oscillators and transistor to drive sound to the speaker […]
CD4011 Oscillator circuit with inverter gates
Here is the tone generator circuit,it is small size. I use IC digital CMOS 4011 quad NAND gate.