By using light sensor with transistor switch, you can make a “LED that turns on when dark” circuit without bothering with microcontrollers.
You will need
-1 transistor (BC546)
– 100k ohm potentiometer
and pliers and soldering iron.
Here is the schematic
and here is how the components are physically connected..
You should be careful for these points when connecting the circuit. Some of them has directions and it will not work if you connect it the other way around…
This circuit is based on information from following sites. You can also just follow the schematics from these sites, and should work.
or this project is also nice
I made a “Granny Throwie” with this circuit, so that the LED will turn on only in dark. I am hoping to send this piece to Stitches on the Bridge project, a massive guerilla knitting over the Skye bridge in Scotland. Perhaps “Granny Throwie” will light up the Skye bridge some day..