The Northern Telecom Displayphone
Description
The Northern Telecom Displayphone is an integrated voice/data terminal (IVDT) device designed to merge telecommunications and computing introduced in the early 1980s. The device allows users to make voice calls while simultaneously sending and receiving data. It was intended for professional environments, offering capabilities such as electronic messaging, directory services, and rudimentary data processing (Datapro, 1988). Encased in a beige plastic shell with a sleek yet functional design, the Displayphone foreshadowed the future of smart communication devices.
At its core is the CRT display unit, that supports ASCII and ANSI character sets. The handset, positioned to the right of the display, functions as a traditional telephone receiver, with speaker volume control accessible on the side of the keyboard. The lower keyboard provides a retractable or detachable full-travel QWERTY-style typing interface. Above it, the upper keyboard houses essential telephony and soft-function keys, including a standard telephone dial pad and dedicated buttons for directory access, call hold, redial, screen toggling, and volume control (Datapro, 1988).
The Displayphone was an ambitious technological innovation of the early 1980s that demonstrated the influence of Northern Telecom Limited in the telecommunications industry as well as the viability of voice and data integration, but ultimately failed to achieve widespread adoption due to a stagnant market that was unable to reach a mainstream consumer base and lacked practical applications of the product.
Models
Northern Telecom released several versions of the Displayphone, each designed to meet different user needs:
Integrated Voice/Data Terminal (IVDT)
The Displayphone was part of a broader technological push in the early 1980s to integrate voice and data into a single device. IVDTs were designed to improve efficiency by reducing costs, simplifying office setups, and enhancing access to shared resources (Shellenberger, 1987).One of the key advantages of IVDTs was their ability to facilitate resource sharing, particularly in environments where occasional access to modems or printers was needed by multiple users. In law offices, for instance, rather than equipping each desk with an individual modem, an IVDT-enabled system allowed multiple users to share a single modem or printer, optimizing costs and space. Additionally, the integration of telephony with legal applications software was a major selling point. IVDTs were not just standalone communication devices but were intended to be workstations tailored to specific professional needs. The Displayphone embodied these benefits, offering a streamlined interface where users could touch the screen to look up and dial a phone number, take notes, send intra-office messages, and access office software and electronic mail (Shellenberger, 1987).
The introduction of the Displayphone in February 1981—developed by Bell-Northern Research in Ottawa and manufactured by Northern Telecom in Belleville, Ontario—marked a significant milestone in telecommunications technology. It was the first commercially available IVDT, combining telephony and data capabilities into a single device. The specific artifact examined in this study was manufactured in March 1984. It was classified as a telephone appliance and a Class A computing device, complying with FCC Part 68 rules.
The primary market for the Displayphone consisted of knowledge workers, particularly those in communications-intensive roles engaged in the creation, manipulation, analysis, and dissemination of information. Early marketing efforts targeted executives in brokerage, financial planning, market research, real estate, and telemarketing—professions where quick access to and transmission of data were essential (Dataquest, 1986).
Despite its technical capabilities, the Displayphone faced substantial market challenges. The high cost, resistance to change, and competition from emerging personal computer-based voice/data solutions limited its adoption. Additionally, a major application that could drive widespread demand for IVDTs never materialized. The broader IVDT market remained sluggish, hindered by a lack of compelling use cases that could propel it into mainstream business environments (Datapro, 1988).
The rapid rise of personal computing networks and online services in the late 1980s and early 1990s further marginalized IVDTs. As personal computers became more integrated with telecommunications capabilities, the standalone IVDT model lost relevance. The introduction and rapid acceptance of the World Wide Web in the 1990s (Jacksi & Abass, 2019) rendered videotex services—one of the primary applications of IVDTs—largely obsolete. This shift ultimately sealed the fate of devices like the Northern Telecom Displayphone, which, despite its innovative design and early influence in the telecommunications industry, was unable to find a sustainable market in an evolving technological landscape.
