Difference between revisions of "TEC 440"

From Terminals
Jump to: navigation, search
m (tweak formatting)
m (formatting)
 
(5 intermediate revisions by the same user not shown)
Line 2: Line 2:
 
| manufacturer = TEC
 
| manufacturer = TEC
 
| model = 440
 
| model = 440
| image = TEC_440.jpg
+
| image = TEC 400.jpg
 
| intro_month = June
 
| intro_month = June
 
| intro_year = 1972
 
| intro_year = 1972
 
| intro_price = $2,245
 
| intro_price = $2,245
 
| interface = RS-232C
 
| interface = RS-232C
| baud_rates = 110-9600
+
| interface2 = TTL serial
 +
| interface3 = 20 mA current loop
 +
| interface4 = 60 mA current loop
 +
| baud_rates = 110, 150, 300, 600, 1200, 1800, 2400, 4800, 7200, 9600
 
| display_size = 12-inch
 
| display_size = 12-inch
 
| refresh_rate = 60
 
| refresh_rate = 60
Line 14: Line 17:
 
| char_resolution2 = 72x24
 
| char_resolution2 = 72x24
 
| graphics_resolution =  
 
| graphics_resolution =  
 +
| attributes = normal
 
}}
 
}}
  
The '''TEC Model 440 DATA-SCREEN''' is a "fourth-generation"
+
The '''{{PAGENAME}}''' is a "fourth-generation"
asynchronous CRT computer terminal manufactured by '''TEC,
+
asynchronous CRT computer terminal manufactured by '''TEC, Incorporated'''
Incorporated''' of Tucson, Arizona. Formally introduced in June 1972,
+
of Tucson, Arizona. Formally introduced in June 1972,
 
the Model 440 was designed as a high-reliability, solid-state
 
the Model 440 was designed as a high-reliability, solid-state
 
alternative to mechanical teleprinters, providing a plug-compatible
 
alternative to mechanical teleprinters, providing a plug-compatible
Line 100: Line 104:
 
File:TEC 440 252569897814-9.jpg
 
File:TEC 440 252569897814-9.jpg
 
File:TEC 440 252569897814-10.jpg
 
File:TEC 440 252569897814-10.jpg
 +
File:TEC 400 advertisement 1970-07.jpg
 +
File:TEC 400.jpg
 
</gallery>
 
</gallery>
  

Latest revision as of 14:47, 10 March 2026

TEC 440
TEC 400.jpg
Manufacturer TEC
Model 440
Lifetime
Introduced June, 1972
Introductory Price $2,245
Communication
Interfaces RS-232C,
TTL serial,
20 mA current loop,
60 mA current loop
Baud Rates 110, 150, 300, 600, 1200, 1800, 2400, 4800, 7200, 9600
Display
Size 12-inch
Refresh Rate 60 Hz
Character Modes
Resolutions 80x24, 72x24
Attributes Normal
Matrix 5x7

The TEC 440 is a "fourth-generation" asynchronous CRT computer terminal manufactured by TEC, Incorporated of Tucson, Arizona. Formally introduced in June 1972, the Model 440 was designed as a high-reliability, solid-state alternative to mechanical teleprinters, providing a plug-compatible replacement for the Teletype Model 33 and Teletype Model 35 KSR units.[1]

Design and Hardware

The terminal features a 12-inch (diagonal) cathode-ray tube with a high-contrast bonded-glass faceplate. The display logic generates a 64-character ASCII set using a 5x7 dot matrix. A defining hardware feature of the Model 440 is its switch-selectable line length, allowing for either 72 or 80 characters per line across a 24-line display. [2]

Internally, the Model 440 utilizes modular printed circuit boards for timing, memory, and character generation. It supports asynchronous serial communication via an RS-232C interface at baud rates ranging from 110 up to 9600. The memory architecture consists of 1,920 character MOS shift-register storage. The unit also features an auxiliary 9-pin connector to drive an external Receive-Only (RO) printer for hard-copy requirements.

Functional Features

To minimize software overhead for users transitioning from mechanical systems, the Model 440 employs specialized display logic to simulate Teletype-style input/output. The terminal was notably marketed for its ability to handle dual-speed data flows to optimize CPU efficiency during transmission.

The unit mimics the paper-feed behavior of a physical teleprinter by utilizing the bottom line of the screen for data entry, with existing text scrolling upward. Additionally, built-in logic provides automatic carriage return and line feed, preventing the "end-of-line hang-ups" common in older mechanical systems.[3]

History

Introduced at a price of $2,245, the Model 440 was positioned as a premium "electronic teletype" intended to reduce maintenance costs and noise in time-sharing and minicomputer environments. [4] Its rugged design and "handsome styling" were hallmarks of TEC's DATA-SCREEN Series 400 family.

Manx

Images

References

References

  1. Teletype Replaceable Data-Screen Terminal Model 440 Product Description
  2. "Tec CRT Handles Dual Speed Data Flow to Optimize CPU", Computerworld, June 28, 1972, pg. 12
  3. "TEC DATA-SCREEN Terminals (Advertisement)". Datamation. Technical Publishing Co.. November 1972. pp. 33-40. http://www.bitsavers.org/magazines/Datamation/197211.pdf. Retrieved February 24, 2026. 
  4. "Looking back at the Series 400", InfoWorld, August 31, 1981, pg. 44