Check out Climatebabes.com and my solar thermal page at sunreign.com We do LED projects, simple and complex.
Facebook Communicator (prototype)
I made this gadget on a saturday afternoon, to get some skills and hands on knowledg with LED sign making. If you want one (any design) check out my LedRepair page. Any profit I make goes into cheap clean energy technology and driving awareness through my websites.
I used 5 mm classic dome shaped rgb leds I had lying around, they are not the best because they project light to the front. RGB leds have three leds inside with a common cathode (negative pole).
Red is driven by 2.2 volt and blue by 3.3, the battery delivers 3 volt (2 x 1.5 volt rechargeable) so to be correct I should put a little resistor in front of the connections for the red string (r=v/i, v=0.8 volt, i = 42*.02 A, r=0.95 Ohm, not much). I learned that LEDs are somewhat tolerant so I ommitted a resistor for now (plus I don't have one).
The initial plan was to use a 9 volt battery but that requires putting LEDs in series and that's impossible with rgb leds (blue would have been 3 series, red 4 series), I hope I don't make obvious points.
Below you see how I put the rgb leds in the right design, the idea was to make 'rails' around. This I did with the cathode, the anodes I used the leads without to much care. It is still possible to wire up the green LEDs. With some tape you can easily isolate the layers.
I wanted the thing to be self contained and be usable somewhat as a sign in a contest. So the judge will take the whole thing and turn it either up or down and the light will follow the action. I made it work using two switches. I used a piece of aluminum to make a channel in which I put a used 9 volt battery to serve as weight.
One cold use micro reed switches and a magnet to do the same thing cheaper (more colors also).
If you like this project and want to order some of these contact us through the LedRepair page. We can make anything.
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