From electro-music.com wiki

Schematics: Buchla Pulser Schematic From The Music Easel

DIY | Music Easel | Pulser | Buchla

Buchla Pulser schematic from the MusicEasel , redrawn by A. Lanterman and Modified by Dave Brown , more info : http://modularsynthesis.com/lanterman/puls-cross-timbre/pls-crs-tmb.htm