Car Head Lights Turn Off

This circuit when setup in a car automatically turns off the head light after a preset time after the ignition switch is turned off.So you can walk out easily from the dark garage in the light of your car.

Circuit diagram :

Car Head Lights Turn Off  Circuit Diagram

When the ignition switched on first the voltage from battery is fed to the relay through diode D1.When the ignition switch is turned off it produces a negative going pulse at the pin 2 that triggers the timer. The output of the IC goes high for the time set by R1  .This makes the transistor Q1 to conduct to energize the relay to drive the headlight.After the set time the light goes off.With the value of components used you can make a setting from 10 S to 60 S.
Notes :

• Assemble the circuit on a good quality PCB or common board.
• Fit the potentiometer on somewhere on the dashboard so that  you can easily set the timing.
  

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Sound Activated Lights

This diy sound activated lights circuit turns a lamp ON for a short duration when the dog barks (or a relatively strong sound) giving an impression that the occupants have been alerted. The condenser microphone fitted in a place to monitor sound and generates AC signals, which pass through DC blocking capacitor C1 to the base of transistor BC549 (T1). Transistor T1 along with transistor T2 amplifies the sound signals and provides current pulses from the collector of T2. When sound is produced in front of the condenser mic, triac1 (BT136) fires, activates lights and the bulb (B1) glows for about two minutes.

Assemble the sound activated lights circuit on a general purpose PCB (circuit board) and enclose in a plastic cabinet. Power to the sound activated switch circuit can be derived from a 12V, 500mA step-down transformer with rectifier and smoothing capacitor. Solder the triac ensuring sufficient spacing between the pins to avoid short circuit. Fix the unit in the dog’s cage or close to the sound monitoring spot, with the lamp inside or outside as desired. Connect the microphone to the sount activated lights circuit using a short length of shielded wire. Enclose the microphone in a tube to increase its sensitivity.

Caution. Since the sound activated lights uses 230V AC, many of its points are at AC mains voltage. It could give you lethal shock if you are not careful. So if you don’t know much about working with line voltages, do not attempt to construct this circuit. We will not be responsible for any kind of resulting loss or damage.

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Two Colour LED Lights Bar

This circuit is a circuit run on alternating two insignia.It uses the 2-color LED with a built-participating in 3-pin single.This preference look for away the glow of every LED until the base.It turns alternating to one more color.In in the least way to the moon on the moon essential end, afterward the LED end of the first LED.Circuit consists of, nand gate ic.Two 10 Counter circuits IC, and IC JK flip washout .Company of the circuit is not speaking into 3 sets.It is a solid of gesture generators, a set of parade and control.Set the signal generator is IC1a,and IC1b quantity 4011 is a signal generator.The R2, R3, C2 determine the frequency generated.The hint is fed to a set of impressions is the figure 4011 IC2 and IC3.The 10 counter circuits to output to the LED, and Is the same, but the effort should ensue performed individual by the side of region.

Therefore, the show from pin 11 of IC 2 and tested pro D2 and D3,To pin 3 of IC4.The integrated circuit IC 4 is a JK flip slump is connected to a T flip flop.The signal input pin 3 and pin 1 is the output hint at.Which sends a signal to the Reset IC either obstruct working.IC4 on the anniversary, it want output the originally moment in time, happening contrast to pin1.IC3 progress to handiwork, IC2 stopped.
IC2 is controlled by signals from pin 1 of IC4, to IC1c.earlier to control IC2.The IC3 is connected to pins 1 through D1 to the control again

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The Nite Rider Lights Circuits Diagram

As a keen cyclist I am always looking for ways to be seen at night. I wanted something that was a novelty and would catch the motorists eye. So looking around at my fellow cyclists rear lights, I came up with the idea of NITE-RIDER. NINE extra bright LEDs running from left to right and right to left continuously.

It could be constructed with red LEDs for use on the rear of the bike or white LEDs for an extra eye catcher on the front of the bike. All ICs are CMOS devices so that a 9V PP3 battery can be used, and the current drawn is very low so that it will last as long as possible.

Nite Rider Lights Circuits Diagram

Parts

1 555 timer IC4.

1 4027 flip flop IC1.

2 4017 Decade Counter IC2 and IC3.

3 4071 OR gate IC5, IC6 and IC7.

1 470 Ohm resistor 1/4 watt R3.

2 10K resistors 1/4 watt R1 and R2.

1 6.8UF Capasitor 16V C1.

9 Super brght LEDs 1 to 9.

1 9V PP3 Battery.

1 single pole switch SW1.

1 Box.

How This Circuit Works.

IC4, C1, R1 and R2 are used for the clock pulse which is fed to both the counters IC2 and IC3 Pin 14. IC1 is a Flip Flop and is used as a switch to enable ether IC2 or IC3 at pin 13. IC7a detects when ether IC2 or IC3 has reached Q9 of the counter pin 11. IC5, IC6 and IC7a protects the outputs of the counters IC2 and IC3 using OR gates which is then fed to the Anodes of the LEDs 1 to 9.

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