It has been a long time since I flew as a private pilot, but I vaguely remember a piece of equipment we used in calculating some aspect of our flight planning that bore the name Jeppson or something awfully close. FWIW.
You’re thinking of Jeppesen. He was an airline pilot who began drawing up hand sketches of approaches to airports, showing obstructions, etc and selling them to airline pilots. Later he expanded the service to much wider coverage of airports and airways and offering subscriptions to the general aviation public. I think his company did also sell a version of the “E6B computer”, a slide rule like calculator for working out headings, ground speed, etc. The Jeppesen charts could be carried in a specially made briefcase usually known as a “Jepp case” which was usually the mark of a pilot on the way to work.