Business communication has relied on multi-line and private exchange systems since the early days of the telephone industry. Today’s IP based business telephones and software based telephone clients may seem like distant relatives of yesterday’s analog and digital phones. However, our relationship with them and their basic interface remains intact through time.
I’ve had the opportunity to install, configure and repair business telephone systems of many varieties over several decades. Here are some I’ve collected through the years:
It seems odd that the Nortel Norstar digital phones only required two wires, while today’s IP phones require eight wires.
Inspired by the AT&T Merlin Key System, the original System 75 phones had a unique style.
The AT&T Horizon Key System is typical of the analog electronic key systems of the late 1970s and 1980s.
In 1977, AT&T introduced the Dimension PCM analog electronic PBX. Burdened with deregulation, AT&T introduced a technologically outdated PBX system at virtually the same time that competitors ROLM and Northern Telecom introduced pioneering digital PBX systems. The Dimension console and equipment cabinets even featured simulated woodgrain accents to firmly cement them to the 1970s.
This Automatic Electric five line 1A2 key system phone required a 25 pair cable to connect it, but featured LED line indicator lamps.
The Stromberg-Carlson five line 1A2 phone with rotary dial in stylish orange.