Electrical Experimenter 1914-12
An issue of Hugo Gernsback's Electrical Experimenter, a New York monthly from December 1914 for amateur radio builders and home experimenters. Line diagrams in blue ink show coils, relays, crystal detectors and knobs in cutaway and plan view, with hand-lettered callouts and figure numbers, plus a gridded "Latest Patents" page of numbered device vignettes.
