Give me a day to locate the original schematic. if it doesn't show up, I will print one up and upload it. I am working on a project right now that I had to build up a slightly modified version for some test setups. One thing that caught my attention is that in one of the tests I have to drive a completely reactive load at several watts and it was completely stable across the range. Also, I hope you aren't one of those nuts that demands 0.001% harmonic distortion
