Attached is a schematic from the STK500 kit.
Can I get negative 5V from this?
edit: Rephrasing the question: How can the above circuit be modified to give +5V and -5v? Will I have to change the transformer side? I already have the components and now I found that I need a +/-5V.
I found one circuit using the 555 and I am going to try and see if it works. Other ideas are welcome.