>You didn't specify what kind of transistor you needed to use, so I'll >suggest a unijunction transistor. >Good luck finding them though, I don't know if they are still made. A TO92 case SCR makes a nice programmable unijunction transistor. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: "[PIC]:" PIC only "[EE]:" engineering "[OT]:" off topic "[AD]:" ad's