On the Circuit 1 page, you'll find an article I wrote for High Power Rocketry magazine about the timing circuit used for Nike 2000.  The Circuit 2 page is incomplete at this time.

My first timing circuit was made entirely from Radioshack® parts and was etched using one of their kits. I still etch the circuit board for the timing circuits but the design has changed drastically through the years. Now I use surface mount components and size is more critical now.

I have also changed the way that I activate the timing circuit. I started out with a roller microswitch. This had many problems. Specifically, the tolerance that it required was small. It had to be carefully placed or it would have difficulties. Now I use replacement refrigerator switches or acceleration switches for a few applications.