Serial Terminals
Before bitmapped graphics were commonplace as in today's personal computers, interactive computing took place through a terminal. The most common type of terminal was based around a CRT that could display a rectangular grid of characters. The most common size was 24 lines of 80 characters each, although different terminals had different capabilities. Some terminals could display a limited form of graphics using a graphic character set.
Printing terminals were also in use, using tractor-feed fanfold paper (LA-36, LA-12), roll paper (ASR-33 teletype), or rolls of thermal paper (HP2621P, TI Silent 700).
The terminals connected to the computer with either an RS-232 serial interface or a 20 mA current loop interface. The latter was for compatability with earlier teletypes.
The first personal computers also used terminals for interacting with the user. Early S-100 bus based machines and machines running the CP/M operating system commonly used serial terminals.
My first experiences with computing were through terminals, primarily the LA-36 (an earlier, slower variation of the LA-120), the Beehive terminals and HP2621A terminals at the University of Delaware. I also used PLATO system terminals (which were more like standalone personal computers).
Before interactive computing through terminals, users typically interacted with the computer through punched cards for input and line printers for output.
Modern computers don't have much need for a plain old character terminals with their limited display capacities. However, the concept of a terminal is still around in the form of network "thin clients" that consist of a display, keyboard and mouse and rely on the network for storage. In the late 1980s, serial terminals were displaced by X Window System terminals.
Current holdings in the collection:
- Digital Equipment Corporation
- LA-120
- Acquired: 23-Nov-2005 on e-bay in conjunction with the PDP-11/03.
- Status: Working.
- Documentation:
- EK-LA120-UG-001 LA120 User's Guide September 1978
- manx search
- Photos (the LA-36 is nearly identical in appearance to the LA-120)
- Serial Number: PN 18228
- Accessories:
- wire output tray
- Several boxes of multipart forms fanfold paper
- VT-100
- Acquired: 23-Nov-2005 on e-bay in conjunction with the PDP-11/03.
- Status: Working. Needs video adjustment.
- Documentation: Yes
- LA-120
- Heath/Zenith
- Z-19
- Acquired: 02-Jan-2006 for $52.56 on ebay
- Status: Untested, damaged during shipping, needs mechanical repair; reported working
- Documentation: Yes
- Z-19
- Hewlett Packard
- HP1351A Graphics Generator
- Acquired: 24-Dec-2005 for $134.72 from government surplus
- Status: Inspected
- Documentation: Yes
- HP2397A
- Acquired: 24-Mar-2006 for $9.99 on ebay
- Status: untested, reported working. Needs HPIL keyboard and RGB monitor.
- Serial Number: 3019Y02268
- Documentation: Yes
- HP2621A
- Acquired: Purchased from a used equipment vendor in 1986.
- Status: Power supply failure, needs repair.
- Documentation: Yes
- Photos
- HP2621P
- Acquired: 9-Mar-2006 for $35 on ebay
- Status: untested, reported working, needs keyboard
- Documentation: Yes
- HP1351A Graphics Generator
- HP2648A #1
- Acquired: 28-Jan-2006 for $19.99 on ebay, keyboard gifted
- Status: Untested, unit in fair condition, capstan roller has deteriorated on both tape drives, two missing keycaps on the keyboard; reported working.
- Documentation: Yes
- HP2648A #2
- Acquired: 4-Feb-2006 for $50 cash from a dealer with an extra keyboard included (used with unit #1 above)
- Status: Working. Tape drive capstan rollers are intact.
- Documentation: Yes
- VIP7809
- Acquired: 28-Feb-2006 on ebay for $16.51
- Status: untested, reported working
- Documentation: No
- Accessories: rugged military shipping crate
- 3180
- Acquired: 9-Mar-2006 for $20 on ebay
- Status: untested, reported working
- Documentation: No
- ADM-3A
- Acquired: 27-Mar-2006 for $74 on ebay
- Status: untested, reported working, DIP switch face plate missing
- Serial Number: 68667
- Documentation: Yes
- ADM-5
- Acquired: 20-Apr-2006 for $25
- Status: untested, very dirty
- Serial Number: 21134
- Documentation: No
- ADM-5
- Acquired: 20-Apr-2006 for $25
- Status: untested, very dirty
- Serial Number: 29461
- Documentation: No
- 4010
- Acquired: by donation in Denver and driven to Salt Lake City.
- Status: Working
- Documentation: Yes
- Photos
- 4014
- Acquired: by donation in Denver and driven to Salt Lake City.
- Status: Working
- Documentation: Yes
- Photos
- 4105A
- Acquired: 30-Mar-2006 for $6.50 on dovebid
- Status: Unknown, untested
- Serial Number: 10/85 B011836
- Documentation: Yes
- 9200T (4105A compatible)
- Acquired: 30-Mar-2006 for $6.50 on dovebid
- Status: working
- Serial Number: 09/86 B010382
- Documentation: No
- 9201T (4205 compatible)
- Acquired: 30-Mar-2006 for $6.50 on dovebid
- Status: working
- Serial Number: B022679
- Documentation: No
- 925
- Acquired: 4-Feb-2006 for $115.17 on ebay
- Status: Untested; reported working
- Serial Number: 72102260
- Documentation: No
- Personal Terminal
- Acquired: 16-Feb-2006 for $9.99 on ebay
- Status: Untested, case damaged during shipping; reported working
- Documentation: No
- Model 43
- Acquired: 7-Feb-2006 for $14.95 on ebay
- Status: Untested; reported working
- Documentation: No
- Silent 700, Model 707
- Acquired: from e-bay
- Status: Working
- Documentation: Yes
- Photos
- Accessories:
- additional rolls of paper
- padded carrying case
- ROM option
- Texas Instruments Silent 700, Model 745
- Acquired: 15-Feb-2006 for $75.00 on ebay
- Status: Untested; reported working
- Documentation: No
- W1643 Party Line Terminal
- Acquired: 6-Mar-2006 for $4.00 on ebay
- Status: Untested; reported working
- Documentation: No
- Photos