Do you want a pulse with a defined width, or do you want the transistor to be on whenever the nail blocks the light? With your schematic, the transistor should be on whenever the nail doesn't block the light.jasonspinmaster said:my timer is a LM555, it is the right one?????
i got the schematic from some one on this web page. could you be kind enough as to send me some circits that works as the last 6 months have been hell.
i only need the pulse to fire inconjuction with the nail (trigger)blocking the light