The Forgotten World of Dumb Terminals

From the earliest days of digital computers, researchers often interacted with these novel electronic beasts through blinking lights, paper tape readouts, or teletypes, which were mechanical typewriters often used to transmit telegrams or news briefs over radio or by wire.

In the mid-1960s, computer companies began to experiment with "glass teletypes," which used electronic cathode ray tubes (CRTs) as a display instead of paper. These picture tubes, similar to those used in TV sets, could be written and re-written endlessly with far more display flexibility than a hardcopy printout.

By the mid-1970s, video terminals became the cheapest way for multiple people to interact with a single large, expensive mainframe computer system. Around that time, hobbyists also used them through RS-232 serial port interfaces with the first personal computers. The industry began to call these devices "dumb terminals" because they usually did not contain the capabilities of a general purpose computer (however, many terminals of the 1980s did contain special-purpose software and were far smarter than the "dumb" name implies).

But once personal computers that used TVs or video monitors for displays became common and inexpensive, video terminals began to recede into specialized use cases like accounting offices, library card catalogs, and airline reservation systems. Today, we rarely see them any more, although there are a few holdouts in some large organizations.

I've always been a fan of serial terminals, and I'm sure more than a few of you out there have used them at some point in your lives. So I thought it would be fun to grab a handful of classic terminals from the 1970s and 80s and take a walk down memory lane.

It's worth noting that over the course of at least 20 years, dozens of manufacturers released hundreds of models of serial terminals with many different features—some included color and graphical capabilities. So if you're interested in diving deeper into computer terminal history, this is only a slice of a much wider world. I'd love to hear about your terminal memories in the comments.

1. Sperry UNIVAC Uniscope 300 (ca. 1970)

Sperry designed this very early video terminal to work with its UNIVAC mainframe computer systems. It was created at a time before video display standards were settled, so it has a wide screen with a display ratio more resembling a punched card than a TV set. Accordingly, it also could only display 64 characters by 16 lines of text verses the later 80x24 standard.

(Photo: Mark Richards / Computer History Museum)

2. Lear Siegler ADM-3A (1974)

The ADM-3A was a stunningly compact video terminal released in 1974 that became popular with early personal computer builders due to its relatively low cost ($995 in kit form, $1,195 assembled) despite its drawbacks—it was indeed fairly dumb, and it could only display upper case letters. It did display 80 columns by 24 lines, however.

(Photo: Lear Siegler)

3. DEC VT-100 (1978)

Like other DEC terminals before it (notably the VT05 and the VT52), the VT100 set industry standards that were widely copied by other terminal manufacturers. In this case, the VT100 stood out mostly for using ANSI escape codes that could control cursor and character position on the screen (among other uses). It also shipped with a classic, durable design with a nice keyboard.

(Photo: Digital Equipment Corporation)

4. TeleVideo 922 (1984)

The TeleVideo 922, like many terminals made by companies other than DEC in the 1980s, mostly served as a lower-cost VT100 and VT220 clone (in that it was compatible with standards set by those earlier terminals). It had a green-screen monochrome display and an extended IBM AT-style keyboard with a numeric keypad, which was nice for the time.

(Photo: TeleVideo Systems, Inc.)

5. Visual 102 (1984)

Like TeleVideo, Visual was another popular lower-cost alternative to bigger-name DEC terminals in the 1980s. As can be seen here in this 1984 ad, the Visual 102 targeted the DEC VT102 (an extended version of the VT100), even going to far as to copy its name.

(Photo: Visual Technology)

6. Soroc IQ-120 (1977) and IQ-140 (1978)

This Soroc line of terminals was popular with early personal computer users due to its relatively low cost ($995 for the IQ-120, for example). Both were monochrome with 80x24 character capabilities. The higher-end IQ-140 included the added bonus of a 117-key detachable keyboard, which isn't obvious from this photo.

(Photo: Soroc Technology, Inc.)

7. DEC VT220 (1983)

After the VT100 series, DEC innovated again with the VT220, which was incredibly small and compact for the time. It supported the VT100 standard and also included a new 132x24 character display mode. Also notable was its inclusion of the LK201 keyboard, which was the first computer keyboard to include the inverse-T arrow key design and a general layout that later inspired IBM's famous Model M 101-key keyboard.

(Photo: Digital Equipment Corporation)