Reply To: need help for a scr firing circuit Home › Forums › Power And Battery Circuits › Switching Power Supplies › need help for a scr firing circuit › Reply To: need help for a scr firing circuit March 18, 2013 at 10:52 am #16399 ELEKPAULParticipant Credits: 4 Hi,if you’ re a newbie in spice simulation I suggest you to begin with LTspice, it’s free and easy to useyou can learn how getting started here. I’ve attached two basic SCR LTspice examples, an half wave and full wave rectifier.