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Living Room / Re: Happy Birthday TRS-80
« Last post by 40hz on August 05, 2012, 11:12 AM »[/url])[/i]
According to Wikipedia, the photo in the first post is for the TRS-80 Model III, where mine is the model I (which used a cassette player to save programs not a disk drive).-mouser (August 05, 2012, 09:25 AM)
It is the Model III. IIRC the Model I got yanked from distribution by the FCC because of excessive RF emissions. Radios supposedly used to make all kinds of weird noises if put too close to it.
The Model III was succeeded by the Model 4 (no more Roman numerals!) which was a real nice version. White case, better hardware (128Kb RAM + 4Mhz CPU, nicer 'real' monitor (80x24 vs the old 64x16), larger capacity floppy disks, etc. ) and could run CP/M or an alternative 3rd-party souped-up version of TRSDOS called LDOS. You could have used LDOS on the Model III too although it really came into its own with the faster CPU and higher capacity floppies on the Model 4.
Radioshack also did something called a Model II (and later the Tandy Model 12) (see below), which was their "big iron" offering .
It had two Shugart 8" floppy drives (expandable to 4) and ran CP/M or TRSDOS right out of the box. But you could also get add-ons (hard disk controller, graphics card) and a co-processor board with a Motorola 68000 chip and 512k of dedicated RAM which allowed you to run XENIX on it. That was a popular machine for midsize businesses looking for a relatively inexpensive system to run UNIX-based accounting and payroll apps. It was also popular with what used to be called "data-entry firms" because certain Model II/12 disks could be read by IBM and other minicomputers.
This machine was 'serious business' through and through and competed favorably against some of the lower end DEC and Commodore minicomputers from that era. Which just goes to show how far we've come since then. Especially when you consider any moderately technical hobbyist can assemble a supercomputer quite easily, and for far less money than my sister paid for her single-CPU TRS-80 desktop.


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he might have won a few converts. 


...A 4 drive (RAID1) mirror? 

