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Wing slash making the world smarter Circuit: Components: ·          IC555-1 ·          10k pot-1 ·          1k-5 ·          330E-1 ·          100uf-1 ·          LED-2 Working:                 we are using IC555 in Astable mode. this produces a square wave. which turns ON and OFF the LED. hence by varying the resistance R1 or RV1 we can generate different frequency and duty cycle pulses. the capacitor starts charging via R1 and VR1.The LED remains ON till the capacitor reaches 2/3rd of VCC. at this point, pin 7 and pin 3 go to ground. hence the LED goes off.it takes some time for the charge to drain through RV1. the time taken to discharge is the time LED will remain OFF.  we have connected pin 6 and pin 2. when the voltage reached 1/3rd of VCC pin 2 is triggered causing LED to go high. this disconnects pin 7 from ground. and the cycle repeats. making the LED blink

Wing slash making the world smarter Circuit: Components: ·          mic-1 ·          IC555-1 ·          4027-1 ·          BC547-1 ·          10k-2 ·          100k-2 ·          10uf-1 ·          .01uf-2 ·          LED-1330E-1 WORKING:                 The MIC acts like a transducer. it converts sound into electrical signals. These signals are very low in amplitude. so we use a transistor BC547 to boost the signal hence creating a pulse sufficient to drive IC555 when someone claps. the IC555 is used in Monostable state. when a small pulse is generated when we clap, the IC555 triggers and creates a pulse of roughly 1 second. sufficient for the second stage. if C2 is not present in the kit, replace it with a wire. the output of the IC555 is fed to CD4027 which is a dual JK flip flop. when J=1 and K=1, it toggles for every clock. hence for every pulse created when we clap, the output the IC4027 toggles. hence this entire setup acts like a clap switch. for maki

Wing slash making the world smarter Circuit: Components: ·          IC555-1 ·          IN4007-1 ·          LED-1 ·          330E-1 ·          10k-1 Working: We are using the IC555 to act as a Fire alarm. Pin number 2 is the trigger of IC555, when a negative potential is applied, the IC555 triggers. you can upgrade the circuit to make the circuit turn on for a fixed duration of time when the circuit is triggered or when there is fire. the above circuit turns ON as long as there is a source of heat across the diode. the diode has polarity. and care should be taken while connecting. the cathode should be connected to Pin2 of IC555 and anode to the ground. when the diode is heated, the LED glows.

Components: ·          Transistor BC547 : 1 ·          Light dependent resistor (LDR) : 1 ·          Resistors 330Ohms :1 ·          Resistors 220k :1 ·          LED :1 MISC: ·          Bread board ·          Hook up wires ·          9v battery ·          battery snap Circuit:

         The IC555 is a widely used IC. It has two modes of operation. Namely, Astable and monostable mode. In the Monostable mode, a negative clock pulse to the trigger pin (pin 2) will generate a output for the duration depending on the chosen values of the resistors and the capacitor. In the Astable mode of operation, The IC555 generates square waves with a duty cycle and frequency depending on the chosen values of the resistors and capacitor. for the values I chose, I got a pulse for approximately 1 second. with a 66% duty cycle.          In the schematic, the jumper 1 (JP1) represents the output for which I had connected a LED. and jumper 2(JP2) represents the header pin for input supply. Schematic PCB design

          This circuit will turn on a device preferably a light bulb for a fixed duration of time when it detects movements. this circuit is connected in parallel with a pre-existing switch for the device.Taking example for a light bulb, when a person walks into a room, the device turns ON for a fixed duration of time. If the person wishes to stay in the room for a longer duration, he can turn on the switch manually, since it is a parallel wiring.          This circuit can be used in various applications like staircase lighting or for a room. when someone passes the light turns ON and automatically turns OFF, there by saving a lot of energy.          The heart of the circuit is the PIR module, which sends out a +ve pulse when it detects a movement. PIR stands for Passive Infrared Receiver, implies it does not have a source of IR radiation. some modules have an option for both +ve or a -ve pulse when the motion is detected. the module I secured had the option only for a positive