On Sat, 08 Mar 2008 17:37:27 +1100, Franc Zabkar
put finger to keyboard and composed:

On Sat, 08 Mar 2008 05:27:08 GMT, Ross Herbert
put finger to keyboard and composed:

The LDR senses dusk and
performs the function.

The solar cell is a *light dependent* sensor. It can perform the same
function. Think about it ;-)

Hmm. Here are two circuits which don't require an additional sensor
and two that use a CdS photocell:

http://members.shaw.ca/novotill/Sola...ight/index.htm

- Franc Zabkar
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