Question about building LED sets

[groundhawg]

I bought a flashing LED dash light for my truck last year (volunteer firefighter) and I like it , but I miss having lights in the rear like when I had a roof mounted rotating light. However, I do like the cleaner look of no light on the roof.

The problem is the fancy LED stuff isn't cheap. I really think that I have the mechanical ability to build something simple for my rear window, but not the knowledge to do so. Honestly, I do not know exactly where to start. I have found several articals on-line about builing LED light sets, but most are for a computer tower...not tremendously helpfull for what I am wanting.

I know that building something depends on what particular LED I would get and how many, but I'm really not sure where to begin at on this project. I'm thinking about making a fairly thin bar, probably 1"-2" tall and maybe 10"-12" in length.

Here is what little I do know about making something up...
I would need...circuit board, LEDs, and the capacitor to bring the voltage to the proper level.

What I don't know...how to pick the right LED, how to figure out what capacitor I would need for said LEDs, and how to make it flash.

Anyone know of somewhere that I can find this info...or can walk me through doing this?

 

[DaveBen]

You need LEDs and RESISTORS to make it work. I bought some "Super Bright" LEDs and on the back of the package it tells you what value resistor to use. I used a 680 ohm 1/4 watt with each LED for 12 volt DC. You can wire the resistor to either pin of the LED and it will work. The LEDs are polarized and need + to + and - to -. Good luck.

Dave