12V String LED Flasher Circuit

Looking for a simple LED project? Learn how easy it is to build a LED wig wag string light flasher using just a couple of transistors and few other passive components.

LED Flashing String Lights for Decorating Homes

A LED flasher schematic has also been provided to facilitate the ease of construction.

It’s a simple home fun project that will cost you hardly anything, yet the result will truly amuse you.

Build a simple LED flasher and find ways to use it for decoration. There you must have studied how a transistor can be used to switch a load connected to its collector through a small voltage applied to its base.

The circuit of a simple LED wig wag flasher presented here incorporates just a couple of transistor and is wired as a multivibrator.

The transistors alternately switch the LEDs connected to their collector points to produce an attractive flashing effect of LEDs. The circuit may also be used as an LED emergency flasher unit.

Parts Required for the proposed LED flasher circuit using transistor AMV

You will require the following very few numbers of components to build this circuit: Resistors ¼ watt, CFR, 5%
R1 and R2 = 22 K,
Potentiometers = 47 K,
LED series resistors are all = 150 Ohms,
LED RANDOM COLORED 5mm = 40 nos.
Capacitors Electrolytic Radial
C1 and C2 = 10 µF / 25 Volts,
Transistors, General purpose
T2 and T2 = BC 547 B
General Purpose Board = Small piece 4” by 4”

How to Build a LED String Light AMV Flasher?

The construction of this LED flasher is very simple and is finished through the following simple steps: In the given general purpose board, begin by inserting the two transistors somewhere around the centre of the board.

Keep at least an inch of space in between them. Solder and cut of their leads cleanly. Next fill the board with the resistors and the capacitors. As above solder and cut their leads with the help of a nipper. Now go on interconnecting their soldered leads as shown in the circuit diagram.

The entire procedure should take not more than ½ an hour. This concludes the circuit board assembly.

Take a suitable plastic enclosure, drill appropriate holes for the potentiometers on its front panel. Fix the potentiometers into these holes and connect them to the relevant points of the circuit board with the help of flexible wires as per the circuit schematic.

How to make the LED Series Connections?

To complete the LED string wiring just go through the following points: In one of my previously written articles you can find a detailed discussion regarding the method of connecting the LEDs in series and then in parallel.

Just follow the circuit description of the article and complete the construction of two LED strings. Or alternatively you may just do it as per the wiring diagram of the LED connections in this article itself.

Ultimately you will find that there are two negative points coming out of the two LED strings and a common positive.

How to Test it?

With the help of the given LED wig wag flasher schematic you may proceed the testing of the unit in the following manner: Connect by soldering the LED string outputs to the appropriate points of the circuit board.
Finally connect a 12 supply to the completed circuit assembly, instantly the whole of the LED string will start flashing displaying a true fairy light effect.
This LED string light may be positioned appropriately over the wind shield of your car for a nice little decoration. The potentiometer controls may be optimized as per your taste to get more amazing results from the circuit.

About the Author

I am an electronic engineer (dipIETE ), hobbyist, inventor, schematic/PCB designer, manufacturer. I am also the founder of the website: https://www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials. If you have any circuit related query, you may interact through comments, I'll be most happy to help!