Based on R.G. Keen's schematic, this...
This category includes B-stock boards, verified boards that I used for testing, and a bucket for other items, etc.
Based on R.G. Keen's schematic, this board will provide approximately 18V, 25V, 33V, and -9V off of a single 9V source. Also, it has an option for a 9V sag, letting you dial in a value between 0 and 9V.