I was contacted by a friend recently who was using RC timing circuits in a project he was developing and while using a simulator he was not getting the wave forms and timings he 'intuitively' expected. Speaking to him i realised he was using 'rules of thumb', had not resorted to pen and paper and had jumped into using the schematic editor and the circuit simulator.
I decided to dig out my old calculations for this circuit, to tidy them up and put them on this website. They were very helpful to my friend. Click here to find out more about this project.