Screaming Siren Circuit:-
Siren may be a device that produces clap. they’re the means communication. Sirens will be seen in emergency vehicles like police cars, ambulances and fire engines. Generally, sirens are used as indication or warning. There are different circuits to supply different sirens. Screaming siren lights are those which produces siren betting on the sunshine intensity falling on the circuit. we are able to also call it as Light Activated Alarm circuit.
Screaming Siren Lights Circuit Principle:
The main goal of this cycle is to produce sound according to the intensity of the light falling on the base. As the light fall of the circuit increases, it produces pulses for longer duration and thus produces more noise. The main part of the circuit is the 555 timer IC. Produced oscillations depending upon the intensity of light of the Light Dependent Resistor.
- 555 timer IC
- Light Dependent Resistor (LDR)
- Capacitors C1(10uF), C2(100nF)
- Resistor R1(1k)
- Connecting wires.
- DC battery
Screaming Siren Lights Circuit Diagram:
Screaming Siren Lights Circuit Description:
The main component of this alarm circuit is “555 timer IC”. It is mainly used for the timing applications. It produces the oscillations as required. This can be worked in three modes. These are Monostable mode, A-stable mode and Bi-stable mode. In this circuit, it is worked as a-stable mode. In this mode no outside triggering is essential. The 2nd pin of IC is connected to the 6th pin. Fourth pin is connected to the eight pin and is applied with a supply voltage of 5V. Third pin is connected to the speaker with a capacitor C1(10uF).
In a-stable mode, the second pin is connected to the sixth pin which is uninterruptedly triggers the circuit. As the supply voltage of 5v is connected to the VCC then the capacitor C2(100nF) starts charging through both of the resistors LDR and R1.When the capacitor reaches at 2/3 of VCC then the output pin which is 3 triggers and starts discharging capacitor through R1.Thus gives pulses at the output. When the capacitor is at 1/3rd of VCC, then it again starts charging.
How to Operate this Light Activated Alarm Circuit?
- · Connect the circuit as shown in circuits Diagram.
- · Then apply power supply of 5V DC to the circuit.
- · First place the LDR in Dark.
- · Till now no sound produced at the output.
- · Then place the LDR in light. Gradually increase the light intensity which is falling on the LDR.
- · As the intensity of the light is increasing gradually you can realize the increase in the sound. Now switch off power supply.
Screaming Siren Lights Circuit Applications:-
- This circuit can be used in the civil defense sirens to give caution at the time of natural disasters.
- This can be used as an emergency signals