. So i made a new schematic. This should make the light turn on when there is not laser in the photo cell. Could you please tell me if this will work. Thank You.
..... anyway ..... in this one, the trimmer permit you to regulate the threshold, for take care of the ambient light (is always better to repair the photocell from the most part of the ambient light, anyway, also just placing it inside a little cardboard tube) ..... if the transistor remain on also with the trimmer all in the GND position, it means that your photocell still get too much ambient light, also with no laser ..... in this case, you need to repair it better ..... you can also try to increase the value of the trimmer to 220K, but can't go too far, with the value, so, better take care of the ambient light, before increase the trimmer value (like, placing a cardboard of the photocell diameter around it, closed also on the rear, more long, and painted black inside) ..... and, ofcourse, the contact that you have to use is the NC, not the NO
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As Jerry said, what "photocell" you are using ? ..... i was supposing you mean a normal photoresistor (a picture can help) ..... also, have you tried to mask it from ambient light ? ..... and, it's still on in any position of the trimmer ?
@ Jerry: in this configuration, it must turn on the relais when a certain amount of light hit the cell (IF it's a photoresistor, ofcourse) ..... swapping them, it's always on, until enough light hit the cell and it become turned off (but in this case, is better to change the resistor with a 100K one ..... is much more easy to turn a transistor on, than off, with this easy schematic
