Posted on Feb 5, 2014

The circuit is built around a 555 oscillator (IC1) and an LM386 audio amplifier (IC2). The 555 circuit is an astable oscillator, with the chip output retriggering the circuit. When the key (S1) is pressed, it activates the circuit. The 555 oscillates at a frequency determined by R1, R2, and C1. Potentiometer R2 is used to adjust the tone frequency

Click here to download the full size of the above Circuit.

of the oscillator. Some of the output current of IC1 is coupled to IC2 via a 10- °F capacitor, C2, so that it will be sufficient to drive a loudspeaker. Because the circuit has no gain control, the volume depends on the size and wattage of the speaker.

Leave Comment

characters left:

New Circuits



Popular Circuits

Audio Jammer Noise generator
Receiver Frequency-Converter Stage
Motor Drivers
Temperature controlled oscillator
DIY USB password generator
Sounds From The Old West
AD8195 and DDC buffers
3 voltmeter method of measuring choke
200M FM Transmitter
15 kV @ 30 mA Floating-Output AC or DC High-Voltage Power Supply
robot circuits
A functional block diagram of the MC1428
830MHz RF2104 power amplifier schematic circuit configuration
DW16M-630 type DC excitation switch control circuit