electronics help needed

Viking · Post by **Viking** » Thu Oct 29, 2009 9:18 pm

100 Ohms or 30 Ohms only makes the LED brighter og dimmer. It does not affect fade out time...

a_k · Post by **a_k** » Fri Oct 30, 2009 12:28 am

Viking is right. In the second circuit a resistor parallel to the capacitor is needed indeed. 50-100k would result in a sufficiently slow fade out. I've built the circuit without the base resistor, which was added later to the schematics. And in this version the capacitor got discharged a few seconds after disconnecting it from the battery through the base-emitter junction of the transistors without a bleeding resistor.