Thread: Light Pollution
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Old August 9th 03, 08:39 PM
William Hamblen
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Default Light Pollution

On Sat, 09 Aug 2003 18:21:34 GMT, Alex Kilpatrick
wrote:

I remember a long time ago that street lights would shut off sometimes
when a car drove by and the headlights hit it just right. However, I
don't see that anymore. They may have timer/calendar chips on them so
they are not sensitive to light coming in. In that case, you are out of
luck.


Lights have a photocell and a relay to turn them on at dusk and off at
dawn. There's a capacitor in the circuit to add a little delay so a
brief flash of light won't turn them off. The ones that turn off from
the headlights of a passing car probably are defective. If you can
shine long enough a light bright enough the streetlight goes out. I
think this really is a bad idea. Instead go to a dark location or
watch the moon and planets, which are bright enough for streetlights
not to be a bother.