Re: solar-powered Windex light

Capt. JG wrote:

"cavelamb himself" <cavelamb@xxxxxxxxxxxxxx> wrote in message news:I_OdnTTCE9c-pmzanZ2dnUVZ_o3inZ2d@xxxxxxxxxxxxxxxx

Roger Long wrote:

No.


I don't mean to contradict Roger, but LEDs are current opperated deviced.
So a current liniting resistor in serise will reduce the light output.
But the reostat used for a light bulb won't work.
Resistance would likely be way too low.


Richard
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Now just why the HELL do I have to press 1 for English?
John Wayne



Can you point me to an appropriate reostat?


More like a variable resistor.

Reostats are usually wire wound for higher current - like a light bulb.

LEDs, at least the one's I'd use for this kind of thing, barely pull 10mA/diode. A single bright white LED running at 12 volts - golly,
I'd start about 200 ohms fixed resistor and see how bright the light is
at 50 feet.
???

Richard

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(remove the X to email)

Now just why the HELL do I have to press 1 for English?
John Wayne
.

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