On Tue, 5 Nov 2002, Roman Black wrote: *>No, the cap goes between the base and EMITTER, *>NOT the collector! Putting the cap between base *>and collector is stupid as it couples the back emf *>to turn the transistor back on, exactly the reason *>you are getting vibration now. He isn't getting vibration, he said it does not work at all, it does not couple back emf anywhere (it's not stupid, it's a Miller integrator which makes the capacitor appear beta times larger exactly when it matters for noise (during the transition)(but without the leakage, bulk and price of a 100uF filter cap), and *I* said put it between C and B, not you. Please check your facts before contra-posting. You can also build the circuit and see for yourself. Peter -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics