hi
i love combining electronics and magic, my latest project to cut a long story short,
requires a way of switching an electromagnet off and on while moving it across a surface at a distance of a couple of inches,
so i'm looking for a sensor that senses the edge of a white sheet of paper against a black background.
the trigger surface and background can be any colour,white a4 paper against a black background would be convenient
i cant have a light source on the surface, so I cant use a LDR.
thank you
doug
i love combining electronics and magic, my latest project to cut a long story short,
requires a way of switching an electromagnet off and on while moving it across a surface at a distance of a couple of inches,
so i'm looking for a sensor that senses the edge of a white sheet of paper against a black background.
the trigger surface and background can be any colour,white a4 paper against a black background would be convenient
i cant have a light source on the surface, so I cant use a LDR.
thank you
doug