| Description | |
| Manufacturer | Tandy Radio Shack |
| Model | TRS-80 Model I |
| Date Announced | 1977 |
| Date Canceled | 1981 |
| Number Produced | Hundreds of Thousands |
| Country of Origin | USA |
| Price | About $600 for the base machine with display |
| Current Value | $25-$250 |
| Specifications | |
| Processor | Zilog Z80 |
| Speed | 4 MHz |
| RAM | 4K to 16K internally, 32K more with the expansion interface |
| ROM | 4K (12K on Step II) |
| Storage | Cassette tape, 5.25" floppy disks (optional) |
| Expansion | TRS-80 Expansion Base |
| Bus | N/A |
| Video | 64 x 24 text, 128x48 graphics (modified text) on a monochrome monitor |
| I/O | Parallel and Serial with expansion unit |
| OS Options | TRS-DOS, NewDOS, others. |
| Notes | The TRS-80 was one of the first "complete" personal computers available. It was introduced at around the same time as the Commodore Pet 2001 and the Apple II and competed with those machines directly. |
| Related Items in Collection | Expansion Interface, Disk drive, some software, most manuals, TRS-80 Model I without the Numeric Keypad |
| Related Items Wanted | Additional software, disk drives, voice synth unit, other Tandy peripherals (modem, hard drive, etc.) |
The TRS-80 Model I came in several different versions. You could get the machine either with or without a numeric keypad and as a Step I or Step II machine. The Step I model had a 4K BASIC with very limited capabilities. The Step II version had a 12K BASIC which was far more useful.
This machine is a Model I, Step II with the numeric keypad, expansion interface, drives and (flakey) monitor.
Thank you to Bob Wickman who donated this machine.
(Submitted August 25, 2009 20:26:56 by Natan Saidon)
I think you should update the specifications table, the TRS-80 Model 1 COULD use hard disks.
(Submitted May 1, 2008 12:02:06 by Gary H)
I ran a bbs for 2-3 years on a trs-80 model 1 (Horizon in the bay area if anyone remembers). I had 3 80 track double sided drives overtracked to 84 tracks running the newdos/80 operating system in addition to the 40 track ds drive used as the boot drive. It was one heck of a system back then. The only issues where the tin contacts which corroded and caused reboot/hang issues and the monitor which was intermitten. I would sometimes have to slap the monitor HARD to get it to display when it flickered off.
(Submitted February 28, 2008 18:14:17 by Bob Whitney)
I purchased my TRS-80 in 1977. I eventually purchased an expansion interface (Not Tandy), 2 floppy drives (single sided) and an Epson MX-80 printer. I also found out that I could use both sides of the floppies by punching holes in the disks. I also used Electric Pencil and Visicalc along with a neat game , Taipan, which actually had graphics showing ships sinking. Looking back, it was quite an experience and it helped me to understand computing and helped me on the job.
(Submitted August 26, 2007 23:17:45 by dean)
The different versions were called LEVELS *not* steps. Level 1 and Level 2.
(Submitted January 27, 2007 19:31:32 by Todd)
I still have my TRS-80 from when I bought it new in 1978. Upgraded to 16k LII but could never afford the EI and disks as a high school student. I have given my TRS a new purpose in life as the brains behind the resurrection of my college invention: a beer drinking game. You can see it on Google video at http://video.google.com/videoplay?docid=1395261366387688580&q=electronic+quarters&hl=en or search for Electronic Quarters. I used the TRS32 emulator to write the program file to an audio CD-R instead of a tape.
(Submitted December 2, 2006 08:46:57 by Sam Sorrell)
The Model I had a 64x16 display, not 64x24. Also, it was roughly a 2MHz machine (acutally something like 1.77MHz), not a 4 MHz machine. Although I think there was an aftermarket mod that would give you close to 4MHz.
(Submitted September 29, 2006 21:56:06 by Tony)
I bought my first TRS-80 Model I keyboard in the UK in 1980. It was sold by a third party who imported it without screen or tape player - and an RF modulator to enable it to be plugged into a standard UK TV. Opening it up it said it was a level I 4K machine, but it had been upgraded to Level II 16K. I upgraded it with low power chips to 48K - and found that if I cut out the logo on the left of the keyboard the numeric keyboard sockets were there - I bought some keys and created my own numeric keypad by soldering them to the motherboard. Adding a non-standard (Gnomic) interface enabled me to plug in disk drives and a printer, and when Visicalc was introduced for the machine it was invaluable to me as an accountant.
(Submitted August 18, 2006 11:27:18 by Dave Lay)
I have a TRS80 Model II with desk, expantion drive and printer that I paid more than $8K for new. It is in great condition and I am interested to know if there is any market for this complete unit.
(Submitted August 12, 2006 22:39:47 by Jeff)
I have a TRS80 Model II with built-in dual 8 drives, plus the quad 8 external unit, for sale.
(Submitted August 12, 2006 07:23:03 by joe)
i bought mine with 16k (deluxe version) lol for 950 bucks still had it and fired it up here and there until 2002 man i long for those days again
(Submitted August 12, 2006 06:06:32 by Caranne)
My father gave me a TSR-80 after he upgraded to a IBM-compat. He was always into technology. i.e.- as soon as he could buy a 20 moniter in the 1990's he did, for $2000. That was when a 15 could be had for $300+/-. Anyway- never could do much with it- I think I still know BASIC, learned it in 8th grade... The thing I remember most about it is when I had my pet Macaw in my bedroom, I took a nap and woke up to find a hole in the dust cover and half the keys pulled off.
(Submitted March 2, 2006 14:46:40 by Sam Brooks)
I have a Trash 80 Model I w/expansion interface, LII Basic and 48K, monitor and Siemens floppy. Has some kind of I/O problem - won't read or write to floppy, but is functional otherwise. I don't have any use for it - e-mail me if you want it for the cost of shipping it to you.
(Submitted August 18, 2005 12:10:04 by Thenamir)
I learned BASIC on a TRS-80 Model I in 1979 by
visiting the Radio Shack almost daily -- chose
my profession (programming) because of it.
I found a Model I in a mover's trash pile,
keyboard and monitor, but no power cable for the
keyboard -- the one with the 5-pin connector.
Anyone know where I can find one? I'd like to
see if it works. Monitor seems to power up OK.
(Submitted July 6, 2005 21:54:26 by Robb Doggie)
Yep, I had a trash 80. Paid $25 bones for it in 95. Which at that time made it rather obsolete. Nice toy though. Used endless loop cassettes, and had a strange compartment in the keyboard. Almost looked like I could stick a few D sized batts there. Never had the gadgets like they had in war games..
(Submitted April 2, 2005 07:12:49 by Robert)
In addition- my TRS 80 is the one piece model- with monitor & keyboard together. This sold at Radio Shack in Glendale Calif in 1980 for $2,000. + tax. ARRRGH Nice site you have..