Hello. im building a arduino project that includes a "revolving light". this light is 5 volt also, my main idea was to run it off the arduino directly but the was not enough power for that.. So i thought of using a 4N35(optocoupler) but i cant get that to work at all. My connections are more or less identical to this (http://fritzing.org/media/projects/o/p/t/optocoupler/images/IMG_1892.JPG) (no that is not mine!) but its the same scematics. the battery and led is oufcourse a 5v source and a revolving light in my system.
Now, i have noticed that i cant start the revolving light if I put in a resistor instead of this ider. And if use my voltage meter to check the 4N35 has some hundred ohms resistance so thats probably my problem.
anyone who have an idea of a different way to solve this for me?