Make a regular light into a blinking light

[fdmsiv]

What electronic apparatus do I wire in between the power source and bulb to make a regular bulk into a blinking light (like a warning light)?

 

[Boatin Bob]

Re: Make a regular light into a blinking light

I would think the quickest and esiest would be to go to an automotive store and get a turn signal flasher, very easy to hook up, some are very quiet so you would't necessarily hear the "Click"

 

[bruceb58]

Re: Make a regular light into a blinking light

If you go the flasher route, you will need an electronic flasher and not a thermal type since you won't have enough watts to operate the thermal type properly.

 

[fdmsiv]

Re: Make a regular light into a blinking light

I have found some ideas, and have narrowed it down to two.

One is the automotive blinker. I am rigging a custom overheat warning alarm. There will be an audible alarm going off at the same time as the light so if it clicks it doesn't matter.

The second is a circuit board chip called a 555 timer. This route looks more complex but is very cheap, about $6 for circuit board and two chips. The solder and wire are about $1.

I think the soldered circuit idea would hold up better in the long run, but the automotive thermal flasher is cheap and easy.

Thanks for all of ya'lls input, greatly appreciated.

 

[bruceb58]

Re: Make a regular light into a blinking light

You won't be able to drive a very big light with the 555 timer. The output of it will have to drive a FET or a transistor to drive the bulb. That is the way I would do it but I am an EE and something like that for me is pretty trivial. A nice thing about the 555 is that you can adjust the frequency of the flash.

An electronic auto flasher is only around $15 or less if you want to go with it.

You can also buy something like this:
http://www.amazon.com/12v-Electroni...6?ie=UTF8&s=automotive&qid=1216154973&sr=8-16

 

[fdmsiv]

Re: Make a regular light into a blinking light

I was going to use this idea

http://www.instructables.com/id/How-to-make-a-fast-blinking-LED-bike-light/


How do I control the pulse rate?

 

[bruceb58]

Re: Make a regular light into a blinking light

Here is the data sheet:

http://www.national.com/ds/LM/LM555.pdf


Go to page 8 for the formulas.

Basically,

The charge time (output high) is given by:
t1 = 0.693 (R1 + R2) C

And the discharge time (output low) by:
t2 = 0.693 (R1) C

Thus the total period is:
T = t1 + t2 = 0.693 (R1 +2R2) C


In that guy's schematic, he has the resistors with the same value so it won't be a 50% duty factor. You can put pots in to vary everything if you want.

He is only driving LEDS so he doesn't need an output transistor. The 555 can only source or sink 200mA.

See why I suggested the $15 part!

 

[Boatist]

Re: Make a regular light into a blinking light

Why not just use a Blinking LED of what ever color you want. Works better and even the very brigtest take almost no current.
Can Get at Radio Shake or Fry or any Good electronic store and only cost $2 at most.