If you feel strobe lights very interesting but are disappointed by the fact that these wonderful light effects can be produced only through complex xenon tube then probably you are quite mistaken.
It is very much possible to make any light a strobe light if you are equipped with a proper driving circuit capable of handling different lighting devices to generate the desired strobe light effect.
The present article shows how a circuit as basic as a multivibrator may be modified in different ways and made compatible with ordinary bulbs, lasers, LEDs to produce spectacular light pulses.
A strobe light may be used for warning, scientific analysis or as an entertainment device, whatever may be the application the effects are simply dazzling. In fact it is possible to make any light a strobe light through a proper driving circuit. Explained with Circuit Diagrams.
Difference Between Flashing and Strobing
A light when made to blink or flash indeed looks pretty eye-catching and that’s the reason why they are used in number of places as a warning device or for decorations.
However a strobe light in particular may also be considered a flashing light yet is uniquely different from ordinary light flashers. Unlike them in a strobe light the ON/OFF pattern is so optimized that it produces sharp dazzling pulsed flashes of light.
There’s no doubt why they are mostly used in conjunction with fast music to enhance a party mood.
Nowadays green lasers are being popularly used as a strobing device in party halls and gatherings and have become hot favorite among the new generation.
Whether it’s LEDs, lasers or an ordinary filament bulb, all can be made to flash or rather strobe using an electronic circuit capable of producing the required pulsed switching in the connected lighting element.
Here we will see how we can make any light a strobe light using a simple electronic circuit.
The following section will acquaint you with the circuit details. Let’s go through it.
Pulsating any Light to Produce Strobing Effect
Through one of my previous articles we came across a nice little circuit able to produce interesting strobe effects over a few of the connected LEDs.
But this circuit is only suitable for driving low power LEDs and thus cannot be applied to illuminate big areas and premises.
The proposed circuit allows you to drive not only LEDs but also powerful lighting agents like incandescent bulbs, lasers, CFLs etc.
The first diagram shows the most basic form of a multivibrator circuit using transistors as the main active components. The connected LEDs can be made to strobe by suitably adjusting the two potentiometers VR1 and VR2.
UPDATE:
I have explained a few transistorized strobe light circuits in this article, however the below shown design is the easiest one and is tested by me. So you can begin with this design, and customize it as per your own preference and liking.
Video Illustration
The above discussed simple design can be further modified as I have explained below for greater control and refined outputs.
The above circuit forms the base for all the following circuits through some suitable modifications and additions.
Using a Flashlight Lamp as Strobe Light
For example if you want to illuminate and pulsate a small torch bulb using it, you would just need to do the simple modifications as shown in the second diagram.
Here by adding a PNP power transistor and triggering it through the collector of T2, a torch bulb is easily made to strobe. Off course, optimum effect is achieved only through proper adjustment of the two Pots.
As already discussed already in the previous section, green laser pointers are pretty popular nowadays; the diagram illustrated shows a simple method of converting the above circuit into a pulsating green laser pointer strobe light.
Here the zener diode along with the transistor works like a constant voltage circuit ensuring that the laser pointer is never supplied with a voltage higher than its maximum rating.
This also ensures that the current to the laser can also never exceed the rated value.
This the zener and the transistor functions like a constant voltage and also an indirect constant current driver for the laser.
Using AC 220V or 120V Lamp as Strobe Light
The next diagram shows how an AC mains lamp may be used as a strobing light source using the above circuit. Here a triac forms the main switching component receiving the required gate pulses from T2’s collector.
Thus we see that through the above circuit designs it becomes very easy to make any light a strobe light simply by doing the relevant modifications within a simple transistor based circuit as exlained in the above examples.
Parts List
- R1, R4, R5 = 680 Ohms,
- R2, R3 = 10K
- VR1, VR2 = 100K pot
- T1, T2 = BC547,
- T3, T4 = BC557
- C1, C2 = 10uF/25V
- Triac = BT136
- LEDs = as per choice
Police Strobe Light Circuit
For the slow astable use the following parts:
- R1, R4 = 680 Ω
- R2, R3 = 18K
- C1 = 100 μF
- C2 = 100 μF
- T1, T2 = BC547
For the Fast astable use the following parts
- R1, R4 = 680 Ω
- R2, R3 = 10K
- preset = 100K
- C1 = 47 μF
- C2 = 47 μF
- T1, T2 = BC547
36 Watt Current Controlled Strobe LED Light
This 36 watt LED strobe light circuit with current control feature was requested by one of the dedicated readers of the website, Mr. Rohit.
The design idea can be learned from the following explnation:
I am trying to make a fast flash LED strobe light like the ones used by cameramen for photography. I have seen some circuits on your website regarding LEDs like constant current driver, powering high wattage LED lights, LED strobe light. However, I think my application is a combination of these projects.
So what I want to do is power 18W or 36W LEDs for 1 microsecond flash and need a constant current driver so that every flash has the same intensity.
I hope to hear from you soon. Feel free to contact me if you have any questions by email or call me to discuss further
The complete circuit diagram for the 36 watt high power LED strobe light with current control feature can be witnessed in the following image:
Parts list
- All resistors are 1/4 watt 5% unless specified
- 1K = 4nos
- 330 ohms = 1no
- 56K = 1no
- 100k preset = 1no
- RX = as given in the diagram
- Capacitors
- 10uF/25V Electrolytic = 2nos
- Transistors
- BC547 = 2nos
- TIP142 = 1no
- 2N2222 = 1no
- RED LED = 5mm 20mA type
- PowerLED = 12V, below 5 amps.
If staring with 12 volt led strove light, how do I modify it to be constantly on ( no strove or flash)?
To make the LEDs ON constantly you can add a switch across the collector/emitter of the transistor which is driving the LEDs. This switch can be used to bypass the transistor switching and allow the LED to light up directly without strobing.
Hi Swagatam
Spoke to you few months ago.
Now I copy a circuit for a strobe LED and works fine with 13.5V except this circuit does NOT work with less voltage, say with 3V or 4V or 5V. It does not work not even with 10V or 11Volts
I use for this 13.5 V circuit a 3.3KΩ resistor, a BC547 transistor, a 150Ω Resistor and two caps. One is 330μF and the second is 100μF on a bread board
What component should I need to remove or replace or add in order this LED to work as strobe like it does now but with 13.5 Volts only
I thank you in advance for your reply
Pat
Thank you pat,
I tried to figure out the values of the parts so that the transistorized astable could be used with a 3V supply.
I used the following calculator to calculate the values:
https://www.homemade-circuits.com/transistor-astable-multivibrator-amv-calculator/
I got the following values:
Collector resistors = 135 Ω
base resistors = 3833 Ω
C1 = 188.2 μF
C2 = 188.2 μF
Use only only one LED with the collectors of the transistors.
Thanks Swagatam,
I should say that the Base (B) of the BC547 transistor is NOT connected anywhere.
Only the Emitter (E) is connected with the 3.3KΩ resistor and the positive side of the 330μF cap and the Collector (C) with the150Ω resistor as well the anode of the LED are connected.
So, is it correct to replace the two resistors with 135Ω and 3833Ω and the two caps with 188.2μF each?
Here a schematic of the circuit I am talking about.
Voltage is 13,3
……3.3KΩ…………………….
+ | |
| | E
330 μF B _ _/ BC547
| .100μf \ C
| | | |
………………..|.|.led.|150Ω.|
_
Regards
Pat
Thank you Pat, However, I am finding it difficult to understand the schematic.
I was actually referring to the following concept:
https://www.homemade-circuits.com/wp-content/uploads/2019/08/strobe.jpg
Sorry Swagatam,
I did draw a little schematic with dots, straight lines, etc. and locate components and values on it just to get an idea but once I send my comment the schematic became a straight line so you cannot read it.
Any how I like this circuit because the strobe is strong as well the timing of the flashes and it does have just 6 components (tiny circuit) that can fit in a locomotive cell but I wish to make it operate with a voltage range from 3V to 17V
If I change the resistors and capacitors with those values you suggested a little earlier you think this circuit will work at 3V?
Thanks
Pat
No problem Pat,
You can try the circuit which is suggested in my previous comment, it should work at 3V also.
However if you want to use with varying voltages from 3 to 17V then that might not work, because varying the voltage will change strobing nature of the circuit also.
I that case I would recommend using a 3.3 V voltage regulator with the circuit, and then it will be possible to use any voltage between 3 and 17V, but again at 17V the 3.3 V regulator can get immensely hot.
The component which I suggested earlier should work with a 3V supply for this circuit (the first circuit from top)….make sure to remove the 330 ohm resistor which is connected in series with the positive supply
OK thanks Swagatam,
I ll try to built this circuit you suggest and see what happens.
Now I remember purchased some time ago from a hobby shop a little electronic circuit with some additional electronic components connected to it, made strictly to be installed on HO scale locomotive engines, and the strobe effect was very nice.
This entire thing include a tiny volts reducer pcb, inlet was 17V or less, with outlet to 5V (this pcb was D-SUN Y4183, size of a stamp) plus whoever build it had installed a resistor on the anode power supply wire to LED plus an eight pin piece, look like timer IC555 but was not an IC555.
I know this, because I try to copy and built several pieces like this, (had purchased a few D-SUN PCB pieces from e-bay) but the IC555 I connect was smoked and burned with 5-6Volts of power to it.
So I do not know what was the IC piece on there, because there were no any letters or numbers to read but it had a very nice strobe LED.
Still works in one of my locomotives
Anyway as I said I will try to build the circuit you suggested
Regards
Pat
Thank you for updating the information Pat, I appreciate it.
Sure, you can try it and let me know how it goes.
As I said Swagatam I ll try to built the circuit you suggested.
You may e-mail me if you come with an idea using less components to built a strobe LED circuit
NOW, I have heard lots of stories about electronic components come from China that are NOT good,although look brand new.
Is any way to test with an Ωmeter the pins of an IC555 timer to see if is good or not?
Thanks
Pat
Thank you Pat,
Yes, there can be parts which are not original, however, unfortunately there’s no way you can test a 555 IC with a multimeter.
OK Thanks