The model 3 is generally regarded as the successor to the Model 1.
Its two 5.25" floppy disk drives could convert model 1 disks.
Initially Radio Shack wanted to sell both the model 1 and 3 at the same time, but the FCC forced them to stop selling model 1. Is so they were discontinued because of the excessive radio noise that they put out.
However, the Model 3 wasn't FULLY compatible with the model 1. There were differences in ROM which meant some programs had to be converted, especially those machine language ones that made ROM calls.
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Model III configurations, by Dave Thompson:
TRS-80 Model III was sold in multiple configurations.
No hardrive configurations included:
Model III with Level 1 ROM, 8k RAM sold for US$799. Model III with Level 2 ROM, 16k RAM sold for $999.
The first floppy drive cost $849, and could store 168k. The second drive was cheaper, and could store more. The price difference is due to the first one included the drive controller. The increased space on the second drive (189k) was due to the first drive must also contain some TRS-DOS (the operating system).
Brandt Daniels adds:
There was also a TRS-80 VideoTex Computer terminal in 1980.
Mark Fowler reports:
I worked for a company in 1982 that had integrated a 5MB, and later a 10MB hard disk into the TRS80 Model III. It was then programmed in FORTRAN-66 as a dedicated medical records system, to mimic the pegbook accounting system in use in the 1980's. We introduced green phosphor, and later amber phosphor display tubes. Some systems were used with a modem to do simple email-type applications, and to access various bulletin boards.
Please consider donating your old computer / videogame system to Old-Computers.com or one of our partners from anywhere in the world (Europe, America, Asia, etc.).
In the later years of TRS-80 Model III I bought a 5meg external hard drive. Then IBM PC came along and I switched to it.
In Kansas City we had a Radio Shack Computer User forum that met once a month in the Olathe Kansas store to share stories of how to program and get things to work. It was a giant help for me. About 30 of us met there. Dad sold me the Mod III that he had just bought for $2500 in 1982/1983. I went without lunches for a year and half to pay for that.
I gave a lecture to a wealthy women''s group on Ward Parkway in about 1984 or so and took my Mod III with me to demonstrate what a computer could do. I kept mentioning how useful the users group was. After 30 minutes a lady said, "Oh, you are not talking about a drug users group." It never occurred to me to explain what a computer users groups was.
Thursday 18th March 2021
LaRoux King Gillespie (United States)
I have some old radio shack programs. and Tandy tapes that could be read by Model III in my day. Who could I donate them to?
Also I have several Basic program text books who to give to?
Thursday 18th March 2021
LaRoux King Gillespie (United States)
In 1983, I worked on one of these for a Radio Shack store that also rented VHS movie tapes. It was a 48k dual floppy machine with a printer attached. My mission was to write the BASIC software necessary to inventory and keep track of which movies were currently rented out. It also printed out the tapes that were available for a given month. I got this job because I had experience with Level II BASIC on the Model I machine. Great times! :)
Friday 26th December 2014
Chuck Rose (Vermont, USA)
NAME
TRS 80 MODEL III
MANUFACTURER
Tandy Radio Shack
TYPE
Home Computer
ORIGIN
U.S.A.
YEAR
1981
END OF PRODUCTION
Unknown
BUILT IN LANGUAGE
TRS-80 Level II BASIC
KEYBOARD
Full-stroke keyboard with separated numeric keypad
CPU
Zilog Z80 then Z80A
SPEED
2.03 MHz
RAM
16 KB (up to 48 KB)
ROM
14 KB
TEXT MODES
32 or 64 columns x 16 lines
GRAPHIC MODES
128 graphic characters
COLORS
monochrome
I/O PORTS
Tape (500 or 1500 bauds), Centronics, RS232
BUILT IN MEDIA
Zero, one or two 5.25'' disk-drives.
OS
TRS DOS (other OSes were available : New DOS, LDOS, MultiDOS, ...)
POWER SUPPLY
Built-in power supply unit
PERIPHERALS
Various Tandy peripherals
PRICE
No disk model : AU$1450 (Australia, 1981) $2495 in 1984 for a complete system with 2x360 KB drives, TRSDOS, 64kb Ram, software and printer