Jony and Ron
Its obvious you are both really good at this and I can only hope to be as good as you guys one day.

I am a software developer and want to learn about hardware, so I am studying part-time and really hoping to pass my IEEE technicians certification/exam so I can become a member. I also want to do the advanced diploma afterwards.

I don't know if I will make it but will keep trying as I am really enjoying the prospect of being able to design my own circuits one day and being able to program them too.

You guys have been a great help so far and a real motivation for me.

Jony
I have built that cicuit with the software you gave me and have found that one of the diodes is on when the switch is open and both the diodes are off (open) when the switch is closed.

I am now going to add voltmeters and amp meters to see whats happening. I will let you know how I go with my analysis soon.

I would also like to know if there is a version of that software that lets you set values for the transistors - currently they default to one value only. It would also be good to label the components.

But apart from that the software is great and is really helping me, thanks again

 

The new version of this software is available here
http://www.yenka.com/en/Free_Yenka_home_licences/