Basic overview of all the controls used in a typical osciloscope and how to set it up. Provides circuit diagrams, output graphs and formulas.
http://oscilloscope-tutorials.com
Slide show tutorial.
http://www.tml.hut.fi/Opinnot/Tik-110.250/1999/Kalvot/vemppa195/
using switching diodes.
http://www.wenzel.com/pdffiles/diodedbl.pdf
http://www.sci.fi/~ijl/yjs1.gif
A free source of SPICE circuit files and tutorials for simulating and analyzing electronic circuits. Links to free downloads.
http://www.ecircuitcenter.com/
Circuit analysis power point slides. Basic and advanced techniques
http://www.newworldci.com/spuee/ee2726/pp.html
http://www.wenzel.com/pdffiles/dividers.pdf
A collection of practical theoretical and empirical data to aid experimenter's using high voltage.
http://home.earthlink.net/~jimlux/hv/hvmain.htm