I have the main unit.
type plain paper facsimile
The Sharp UX-P400 — The Office Fax Machine
The Sharp UX-P400 was a plain paper fax machine produced by Sharp — a professional office communications device from the era when fax machines were essential business infrastructure. As fax technology evolved from thermal paper to plain paper printing in the early 1990s, machines like the UX-P400 offered significantly improved output quality alongside the document transmission capabilities that had made fax the standard for business document exchange throughout the 1980s and 1990s.
The Fax Machine Era
From the mid-1980s through the late 1990s, the fax machine was as essential to business operations as email would later become — providing near-instant document transmission that preceded widespread internet adoption. Sharp was one of the leading manufacturers of fax equipment, producing machines ranging from consumer-grade personal faxes to professional office systems. The UX-P400’s plain paper output represented the technology’s evolution from the curling, fading thermal paper of earlier machines to output quality comparable to laser printer documents.
Historical Context
The inclusion of a fax machine in a retro computer collection appropriately contextualises the broader history of digital communication technology. Fax machines, like electronic typewriters and early word processors, occupied the space between purely mechanical office equipment and the personal computers that would eventually replace them. Sharp’s UX-P400 represents this transitional era in office technology — a period when dedicated devices for specific communication tasks were being gradually displaced by general-purpose computers with appropriate software.