Magic Lights Circuit using Bi Colour LED

This is the magic lights schema which use bi-colour LED as the output to provide the light. The schema uses 14 bi-colour (red and green) LEDs having 3 terminals each. Various dancing colour patterns are generated utilizing this schema considering that each LED can create three various colours. The middle terminal (pin 2) of the LEDs will be the common cathode pin that is grounded. When a positive voltage is applied to pin one, it emits red light. Similarly, when positive voltage is applied to pin 3. it emits green light. And when positive voltage is simultaneously applied to its pins 1 and 3, it emits amber light.

The schema could be implemented for decorative lights. The IC1 (timer IC 555) is applied in astable mode of multivibrator to produce clock signal for IC2 and IC3 (CD4518) that are dual BCD counters.

The two counters of each one of these ICs have already been cascaded to acquire 8 outputs from each. The outputs from IC2 and IC3 are connected to IC4 through IC7 that are BCD to 7-segment latch/decoder/driver ICs. Therefore we acquire a complete of 14 segment outputs from each of the IC pairs composed of IC4 plus IC5 and IC6 plus IC7. While outputs from former pair are connected to pin No. 1 of all the 14 bi-colour LEDs through current limiting resistors, the ouputs of the latter pair are similarly connected to pin No.3 of all the bi-colour LEDs to acquire a magical dancing lights effect.

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Emergency Lights Circuit

The series of emergency lights on this one is a series of emergency lighting is quite simple and not difficult to make. 

Frankly this circuit is not my own design, but at least this series can add to your collection of electronic circuits. The circuit is actually almost the same as the battery charger circuit, its just that in this emergency coupled switching circuit as a circuit breaker when the circuit load is connected to the supply voltage of 220 volts or in other words on the charging position. Meanwhile, when the voltage of 220 volts is lost (PLN lights off), then automatically switches the load switching circuit and turn on emergency lights, where the supply that is used is derived from batteries that have been installed in stand-by position.

In a series of emergencies over the use of LED as a lighting load emergency. And indeed these days we find a lot of emergency lights that are sold in the market that use LEDs, but the LED is used instead led carelessly but has led a gleam of light. The advantages of the use of this led the led is very efficient because once will consume battery power so that with a limited supply to run the series in a long time.

Circuit components used for emergency lighting is not too much, and indeed the components used are the components that are commonly used as components for circuit switching power supply and battery charging. IC LM 317 ic regulator is useful as a producer of supply voltage to supply the batteries. Transistor T2 (BD 140) is useful as switching, ie, decide the flow toward the load at 220 volts PLN lamp life so that lighting will be extinguished. But when the lights PLN did not provide the supply voltage of the transistor T2 will connect the connection from the battery to the load light.

Components used:

Resistors: R1 (180 uhm), R2 (1.2 K), sd R3 R14 (100 ohms), R15 (1 K) and R16 (16 ohm, 5 watt)

Capacitors: C1 (1000 UF)

Diodes: D1 until D5 (IN 4007)

Transistors: T1 (BC 548) and T2 (BD 140)

Zener Diodes 6.8 Volt

IC: LM 317

Battery charger

Transformer

If you are not happy using this type of charger with IC LM317 series like the example above then you can use another type of charger circuit that you think is more appropriate and can work optimally. Then you simply add the switching function by using one or more transistors.

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