This post is to complement the blog post: http://openenergymonitor.blogspot.com/2012/05/emontx-single-ac-power-supply.html
See attached (at the bottom) for the LTspice simulation files. LTspice is a free download and runs well under WINE on Linux Ubuntu. The simulation circuit looks a little different to Fig.1. Since there was no simulation block for the MCP1702 voltage regulator Robert rolled his own!
Big thank you to Robert Wall for his help with this.
For easy reference here are the diagrams from the blog post again:
Fig2. Simulation waveforms under normal operating conditions
Fig. 3 Demonstrating the effect of low value current limiting resistor R1