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ArcticMyst Security by Avery

schematic help

HIMNL9

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Also ..... from the sparkfun link that you have posted ..... if i read correctly the data presented about the photocell, there's something strange in them .....

I have some small photoresistors like that one ..... they say in the page "light resistance 1 Kohm, dark resistance 10 Kohm" ..... mine goes from 250/300 ohm in light, to almost 100Kohm in darkness ..... strange values, as declared .....

Anyway, yes, as lasersbee suggested, you can also swap the places of the 10K and photocell , and change the 10K with a 100K one ..... anyway, you need at least 100K trimmer, better if more .....

If you left the parts as they are now, the relais is on when the laser beam hit the photocell (and as i've said, you need to use the NC contact, in this case, for turn the led off), if you exchange the components, the relais go off when your laser hit the photocell .....

And yes again, you need to place a resistor in serie to the led, sorry, this was my mistake to not have drawed it :(
 









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