The included files are annotated versions of the main (non-power supply) section of the Keithley 225 Current Source. Both files include layers which will allow you, in a suitable program, to hide or show the annotations as appropriate. Also included in the schematic are some notes on suitable replacement parts for the original transistors, most of which are no longer available. More information on the repair effort that led to this annotated schematic can be found here: http://www.eevblog.com/forum/repair/keithley-225-(current-source)-repair/ Matthew Humphrey mhumphrey@gmail.com EEVBlog User Name: motocoder