Do More

Firstly, it demonstrates how the combination of a blue and a white LED can be used to give a realistic imitation of a camera flashlight. Secondly, the good old 555 IC is used in a way many of you may never have seen before alternately mono-stable / astable without too much in the way of external parts. Initially C3 will be empty, pulling output pin 3 to +12 V and causing the blue LED, D1, to light via R3. Next, C3 will charge up via R2. Meanwhile C1 has been building up charge through R1 and D3. If the voltage on C3 reaches about 8 V (two-thirds of 12 V), pin 3 of the 555 will drop Low. So does pin 7, causing the white LED to light, pulling its energy from C1. This energy drops quickly, causing D2 to dim in an exponentially decaying fashion, just like a camera flashlight. Circuit diagram: Bluish Flasher Circuit Diagram Now, because the 555’s output has dropped Low, the voltage on C3 will decrease as well. Ad soon as a level of 4 V is reached (one third of 12 V), the above cycle is repe...

The LM3909 is an integrated circuit (IC) which will flash a light-emitting diode (LED). Using only two extra components and a battery, the circuit is cheap and has a very low current drain from a 1.5 V cell. The circuit can be used as a novelty flasher, an indicator for a dummy alarm bell box, or it could be attached to a torch so that it could be found easily in the dark! The simple circuit Led Flasher with the LM3909 IC Diagram Assembly The circuit can be built on a small piece of Veroboard (the piece shown in Figure 2 measures 15 holes by 10 strips). Using such a board, follow these instructions. 1. Depending on how far away you want the LED from the circuit board, solder a length of insulated wire to each lead of the LED. Use different colours of insulation – say, red and black, connecting the red lead to the anode (a) lead (the longer one) of the LED, and the black one to the cathode (k). Figure 2 shows these leads. 2. Cut the copper tracks as shown in Figure 2, using a 3 mm (1⁄8 ...

ALTERNATING FLASHER ELECTRONIC DIAGRAM The first IC used as a 1 second clock, which generates ON/OFF for the other ICs. Diodes help to cover the IC555 from the peak voltage. Take note that the relay used should have impedance more than 50 ohm. Parts list :     Diode D1-D2 : 1N4001     Zener Diode D2 : 6V     R1,R5,R7 : 3k3     R2,R6,R8 : 68k     Resistor variable VR1 : 47k     Polar capacitor C1 : 10uF/16V     Polar capacitor C3,C5 : 2.2 uF/16V     Capacitor C2,C4,C6 : 0.01 uF     Transistor T1 : BC107/BC148     IC timer : NE555     Relay : 6-9 V     Power supply 6-9 V

Here is a portable, high-power incandescent electric lamp flasher. It is basically a dual flasher (alternating blinker) that can handle two separate 230V AC loads (bulbs L1 and L2). The circuit is fully transistorised and battery-powered. The free-running oscillator circuit is realised using two low-power, low-noise transistors T1 and T2. One of the two transistors is always conducting, while the other is blocking. Circuit diagram :   Portable 230v Lamp Flasher Circuit Diagram Due to regular charging and discharging of capacitors C1 and C2, the two transistors alternate between conduction and non-conduction states. The collector of transistor T1 is connected to the base of driver transistor T4 through current-limiting resistor R5. Similarly, the collector of transistor T2 is connected to the base of driver transistor T3 through limiting resistor R6. These transistors are used to trigger Triac1 and Triac2 (each BT136) through optotriacs IC1 and IC2, respectively, and switch on the ...

Hi friend! to day i share a useful circuit this is a LED Flasher with the LM3909 IC . I suggest a flashing lightweight that is very simple. Because we use figures packages of  IC LM3909 . Advantage of them is utilised rather than of the initial circuit. Using a lot of transistors effortlessly. By you add a capacitor and a resistor for each one. The directed is blinking very quick. In supplement, it has very reduced power consumption, for example, a 1.5V electric battery could drive the directed blinks. And furthermore current is only 0.3mA. you so use it many months.  LED Flasher with the LM3909 IC Circuit Diagram Components C1 = 100uF electrolytic capacitor     IC1 = LM3903 led flasher IC     LED1 = Red LED  Battery = 1.5 Volt AAA

Here is a portable, high-power incandescent electric lamp flasher. It is basically a dual flasher (alternating blinker) that can handle two separate 230V AC loads (bulbs L1 and L2). The circuit is fully transistorized and battery-powered. The free-running oscillator circuit is realized using two low-power, low-noise transistors T1 and T2. One of the two transistors is always conducting, while the other is blocking. Due to regular charging and discharging of capacitors C1 and C2, the two transistors alternate between conduction and non-conduction states. The collector of transistor T1 is connected to the base of driver transistor T4 through current-limiting resistor R5. Similarly, the collector of transistor T2 is connected to the base of driver transistor T3 through limiting resistor R6. These transistors are used to trigger Triac1 and Triac2 (each BT136) through optotriacs IC1 and IC2, respectively, and switch on the power supply to external loads L1 and L2. IC1 and IC2 operate altern...

If you want to make a flasher unit for you motorbike then this circuit is just for you. This simple turn signal flasher circuit can be  easily built and installed in any two wheelers for the desired actions. The circuit employs just two 2-pins instead of 3 as found in other flasher circuits. Once installed, the circuit will faithfully flash the side indicator lights whenever the intended function is switched ON. The circuit also incorporates an optional buzzer circuit which can be also included for getting a beeping sound in response to the flashing of the lamps. . Parts List R1, R2, R3 = 10K R4= 33K T1 = D1351, T2 = BC547, T3 = BC557, C1, C2 = 33uF.25V L1 = Buzzer Coil

For a lower parts count than the 2 transistor multivibrators, 2 LED s can be alternately flashed with a 555 integrated circuit configured as shown in Schematic 2.  I chose the combination of a 2K2 and a 47K resistor to determine the oscillation frequency along with the 10 uF capacitor connected to pins 2 and 6. You can practically change the (R Speed) 47K value to between 10K and 100K or more. Greater resistance = lower speed. You may also wish to connect up a 100K or so potentiometer instead of the 47K resistor for a variable speed version. Additionally, the 10 uF capacitor value can be changed. Feel free to experiment. Although, alternately flashing LED s  is great for the beginner to electronics, the basic one ON, one OFF circuit gets boring quickly. In the next section, we will try to improve the look and try to approximate a flash like a police car (within limits).

If you want to make a flasher unit for you motorbike then this circuit is just for you. This simple turn signal flasher circuit can be  easily built and installed in any two wheelers for the desired actions. The circuit employs just two 2-pins instead of 3 as found in other flasher circuits. Once installed, the circuit will faithfully flash the side indicator lights whenever the intended function is switched ON. The circuit also incorporates an optional buzzer circuit which can be also included for getting a beeping sound in response to the flashing of the lamps. Parts List R1, R2, R3 = 10K R4= 33K T1 = D1351, T2 = BC547, T3 = BC557, C1, C2 = 33uF.25V L1 = Buzzer Coil

Here is a simple circuit that starts playing the car horn whenever your car is in reverse gear. The circuit (refer Fig. 1) employs dual timer NE556 to generate the sound. One of the timers is wired as an astable multivibrator to generate the tone and the other is wired as a monostable multivibrator. Circuit diagram :   Fig. 1: Car reverse horn Circuit Diagram Working of the circuit is simple. When the car is in reverse gear, reverse-gear switch S1 of the car gets shorted and the monostable timer triggers to give a high output. As a result, the junction of diodes D1 and D2 goes high for a few seconds depending on the time period developed through resistor R4 and capacitor C4. At this point, the astable multivibrator is enabled to start oscillating. The output of the astable multivibrator is fed to the speaker through capacitor C6. The speaker, in turn, produces sound until the output of the monostable is high. When the junction of diodes D1 and D2 is low, the astable multivibrator...