|TRS-80 Model I|
WWW.8BIT-MICRO.COM ONLINE VINTAGE COMPUTER MAGAZINE
Although Tandy held for some time that the
Model I was the first personal computer sold, the
Apple unfortunately holds that distinction. What is
noteworthy is that the TRS-80 Model I was the first
personal computer that was mass marketed in
North America and then to the UK. This was accomplished through Radio Shack, a
division of Tandy Corporation.
The Model 1 came with 4K RAM standard and a Basic called "Basic Level 1". The
monitor was essentially an RCA TV with the tuner removed. File storage was on cassette
tape. The Model 1 could be upgraded to 16Kb and Level 2 Basic. Expandability was
gained through the Expansion Interface. This was a base unit connected to the back of the
Model 1 with a short ribbon cable. The composite TV monitor then sat on top of the
Expansion Interface. With an Expansion Interface, you could add additional memory,
control serial devices, use two tape decks instead of just one, and control up to four floppy
Many found the Model I troublesome with the expansion unit. Edge card connections in
many climates would corrode, and lose connection causing the unit to fail. Regular
maintenance could prevent further difficulties. The Model I also had edge card
connections for 5.25" floppy drives, single sides, which could be chained up to 4 drives.
The operating systems (DOS) were many including TRS-DOS, and NewDos 80.
Many Model I survive today and can be seen on eBay for auction daily, and are collectors
items fetching good dollars. If your lucky to have one of these you will not have any
trouble finding someone to take it off your hands. The writer included. :-)
(c) 2004, 2005 Brian K. Hahn
All Rights Reserved.