Need a variable strobe light

[shirata]

Hi All,

I am trying to build a variable strobe light that throws a tight beam at a distance of 2 meters, or about seven feet.
The strobe should be able to vary from 10hz to 100hz+.
But I would buy a light like that if there is one that fits those conditions.

So I have a lots of doubts :
If I have to build it, what is the way to go?Build the strobe circuit from scratch and put a led on it?Or buy a driver that does it?

Do I need a lens to go with the led to focus the beam?Which should I buy?

Should I go with a led, or a commercial led light?

Would appreciate some sugestions, I am out of my depth here...

 

[sv_sniper]

If you like to build from scratch, you may use a 555 timer in "astable" configuration to generate a pulse train in variable frequencies. A variable resistor will do the job.

Then use the output of 555 timer to drive a transistor as a constant current source. The load would be your LED(s). Just remember to bias the transistor properly so that the current flowing through your LED(s) does not exceed the limit.

If you need to have two (sets of) LEDs to blink alternatively, just like the police patrol car, you would need two 555 timers. One timer for switching between two (sets of) LED(s) and the other one controls the (fast) blinking of each set of LED(s). However, the switching transistors of two (sets) of LEDs would be complemwntary (i.e. NPN vs PNP).

The other point is, you will need at least 5V for your 555 timer, unless you are using 7555 (CMOS version of 555 timer / 2V and up would work).

The methods above are quite simple and neat. The transistors are your drivers.


For the optics, you have lots of choices. It depends on what you've gotten. Usually the DIY flashlight vendors have them, both LED modules and optics. Spend some time to browse their catalogs/web pages.

Good luck on building.

 

[glockboy]

Check out the Jeetbeam IBS.