Congratulations - your first darlington transistor circuit :-) Ahhhhh I remember back in the olden days ....... The reason you're probably getting an output with 3 transistors is a very small leakage current from the 1'st transistor is amplified by the 2nd then the 3rd to make your very small voltage into a rather larger one. try using a very large (1 Mohm or greater) between the input and ground. This should help stop any stray currents. ----- Original Message ----- From: "Kieren Johnstone" To: Sent: Monday, August 05, 2002 12:22 PM Subject: [EE]: My magical toy of wonderous mystery (transistor amp?) Hi, I thought I'd try an experiment based on a transistor; the transistor would switch an LED when two wires (one from +5V, other to base of transistor) were attached to a conductor of sorts. It was cool, because you could hold one in one hand, the other in the other, and it would light up - two, even three people work holding hands :) Anyway, I added another transistor, i.e. transistor 1 takes miniscule current, outputs small current, transistor 2 takes small current, outputs slightly larger etc. etc. Anyway, I'm noticing weird results with 3 transistors.. the LED fluctuates in a dim state, even with the wires not touching. Making *any sort* of contact with the wire connected to the primary transistor's base will light up the LED (quite brightly). Don't even need to be near the +ve supply. That's touching even the plastic insulation! Anyway.. I don't know if this is called a transistor amp or what, but I was just wondering why it does this.. am I naturally generating current? :D -Kieren -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads