FRAMINGHAM (07/24/2000) - Ever stop to wonder why telephones have those handy star and pound keys? After all, the keys have been around longer than the voice mail systems that rely on them. Or why the Bell system ran four wires to your house even though you only need two for phone service? Could someone have foreseen the need for DSL way back then?
In terms of foresight, it appears the star and pound keys were put there by design, but the Bell founding fathers didn't have data links in mind when they decided to wire the nation with four pairs instead of two.
According to AT&T Corp., when the Touch Tone phone was introduced near Pittsburgh in 1963 it only had 10 keys, paralleling the 10 finger holes on the rotary dial. Each row and column of keys on the keypad was assigned a frequency, so depressing a key generated a tone comprised of two frequencies.
This layout meant there were two tones left unused on the bottom row, so two keys were added in 1968 for "advanced communications." According to AT&T, one of the earliest uses for these keys was an internal computerized order entry system: Field workers with the company's Western Electric unit could dial in to the system and order parts using a Touch Tone phone.
But the big controversy was what to call the new keys. The star key was universally recognized and easy enough to name, but finding a second symbol with a simple name was problematic. After several field trials, Bell Labs settled on the pound sign, even though many people referred to the symbol as the number sign.
The point is, Bell Labs magicians saw the future and added the keys in anticipation of computerized needs.
The decision to run four wires to the home was apparently driven by simpler motivations. While the history is a little sketchy, it seems the Bell monopoly convinced regulators that installing four wires would lower long-term repair costs. The government bought the argument and let the company recover the added installation costs from the consumer.
Thanks to that, today you can get a second phone line or DSL installed without waiting for your local exchange carrier to roll a truck.
Ahh, the wonders of this miracle of technology called the phone system that we simply take for granted.
John Dix, Editor in chief
jdix@nww.com