@▷ Beep Alarm Circuit Schematic Diagram | Diagram for Schematic

Beep Alarm Circuit Schematic Diagram

This beep alarm circuit would produce beep sound. IT uses IC timer NE555 as an ON/OFF clock. The first timer circuit produces oscillating frequency 1 kHz, whilst the second timer circuit is on the ON or OFF state, depending on the first circuit’s frequency. The output frequency from the first circuit affecting the ON/OFF speed of the second circuit. This will result in the sound produces by the second timer. VR1 is used to change the oscillation frequency for first timer circuit, whilst the VR2 can be used to change the melody of the first circuit’s output. Here is the schematic :

Beep Alarm Circuit Schematic Diagram

Components :
Resistor R1-R2 : 2K2
Variable resistor VR1 : 4k7 ohm
Variable resistor VR2 : 100k ohm
Capacitor C1-C2 : 0.01 uF
Capacitor C3 : 0.1 uF
Polar capacitor C4 : 47 uF/15V
Polar capacitor C5 : 1 uF/15V
IC timer : NE555
Speaker : 8ohm, 0.5W
ON/OFF switch
5-15V power supply

Estimated price : $2