Proton 100 Brochure - Radio Description
The inside folds of the Proton 100 contained extensive descriptions of the radio. One statement of note: the radio's measurement of its sensitivity to weak signals differs from the measurement given in the specifications on another page of the same brochure.
The slightly fuzzy-looking printing was typical of the early 1980s, when photographic composition techniques were in wide use, lacking the definition typefaces that either earlier hot-metal techniques or subsequent digitally-based desktop publishing were able to produce.