Picture? Schematic? Code?Solenoid example:https://www.sparkfun.com/products/11015
I'm not sure what your question is, tbh.Forget the Arduino logic and the transistor and the diode... when you put 5V across the solenoid and take it off again, does it shoot in and out? If that's not working then that's one question; if that is working, but doesn't do that with your Arduino based way, that's a different question.You can't really expect anyone to unravel your circuit from the photos. But on the face of it, if your transistor base is simply connected to pin 13 then yeah I guess the solenoid should "blink".Ooo hang on, I think you might have the diode the wrong way round... looks like you have cathode to collector and anode to positive. That makes sense on the face of it, but this diode is supposed to be back to front, cathode to the positive supply. EDIT- Look carefully at the pic Crossroads posted a bit above.