Personal Computer Museum, Canada's Videogame Museum

TRS-80 Model I

TRS-80 Model I

Speed1.77 MHz
Memory4 KB

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Tandy/Radio Shack


Release Date: 8/1/1977
Manufacturer: Tandy/Radio Shack
Donated By: Jim Thomson
This was Radio Shack's first personal computer, designed in the late 1970s when not much else was available in 'assembled' form. It shipped with either 4 KB or 16 KB of RAM and the Level 1 BASIC was very limited, allowing only 26 number variables, 2 string variables and one array variable. The monitor that came with it was actually an RCA Black and White television with the TV guts removed. You could expand the RAM on the unit and interface cassette drives, disk drives and a serial port. The flaky connections on the expansion boards and serial ports however, led to the eventual nickname "Trash 80".

User Comments
Anonymous on Monday, June 25, 2018
This was my second computer TRS-80 Model 1 Level one, I bought it sometime in late 1978 or early 1979. It provide hours of training and entertainment, I modified it from 4k to 16k with chips from an NCR ECR. lots of fun, now 40 years later still playing with computers I'm an IT Network Manager. Great to see someone preserving these early machines.
Tony G. on Saturday, June 3, 2017
My first computer in 1978. Learning to code in BASIC then launched a huge interest in programming that continues to this day.
Tony Lelieveld VE3DWI on Thursday, January 30, 2014
I remember the "Trash-80" very well. It was my very first computer which I purchased in 1978 (I think). I bought the Model-II with expansion interface but without the monitor as I had a small Black and White TV which I modified the same way Radio-Shack did theirs by separating the TV and Video circuits. I soon got tired of using the cassette tapes for loading and saving programs. I purchased a "Dual-Head-Floppy Drive", bought good quality discs which could be used on both sides, and was loading and saving programs and data in seconds. Since the drive was connected to the "Parrallel printer port" it was very fast compaired to the "Commodore" computer drive as it used the "serial port" which slowed data transfer considerably. I used to write programs in "Basic" with "Peek / Poke" machine language modules imbedded for our kids to help them in math, spelling and other learning skils. If they did better than 70% they could choose to have Choo-Choo trains, or other fun stuff, ride across the screen with basic block graphics. This was a lot of fun for them and they surely improved those skill. There was a TRS-80 computer club held at the Elmira High School started by a teacher who's name I can only remember as "Richie". We learned from each others experiences and mistakes and we always looked forward to these evenings. One High School kid wrote, in Machine Language, his own game where you had to shoot Aliens and as you became better at it the Aliens appeared faster and more numerous. My kids fought over computer time to play this game. When I ended up in Wawa working for CBC as a Remote Area Transmitter Tech, we called ourself RATT's, I wrote an inventory program, with embedded machine language sorting modules, to make keeping inventory a lot easier. As I think of what I paid for that equipment then, with that money I would be able to buy a multi-core super fast machine now. But the fun and learning experience we had made it all worth while. Aaaah the good old days.
Mel Bailey on Wednesday, August 28, 2013
By buying the very first personal computer, a TRS80 Model 1 from Radio Shack in 1975, I became Canada's first personal computer pioneer by starting my own business (Central Consulting in Surrey B.C.) where I wrote TRSDOS-Basic computer programs for government and small local businesses. In 1990 I was invited to work for IBM is the USA and went on to work for all of the computer companies except Microsoft. I retired in Miami Florida in 2010. See more history at
Panzer -Volnteer- on Monday, May 24, 2010
It was my grandfather's first computer, my dad's first computer, I don't remember my first computer, but I wouldn't be surprised of ot was this!!
Manny on Tuesday, February 23, 2010
Remember,,,this was my first computer, I quickly learned how to use an RS232 interface with an acoustic modem. For those of you that have no clue what that is you placed the handset into two rubber cups and your computer actually talked to the modem on the other end. Slow but loyal I was able to term into the FIU mainframe with this thing for over two years. Mine ended up in a model airplane kit factory in Miami.
Bob Bauer on Saturday, February 20, 2010
I owned one of these. It was unbelievably slow. Even the very small Basic programs took forever to load from the cassette tape drive. Overlays were possible but they had to be sequential. The built-in programming language was limited but at least it was always available.
Bob Malins on Sunday, September 27, 2009
I remember the 'Trash 80' well. I was teaching Data Processing at a local high school at the time. Prior to the arrival of the TRS-80 we had used optical cards that had to be sent by bus or driven personally to the University of Western Ontario (Althouse College) to process our programs written in ICL. With about a one week turnaround time you can imagine the frustration when a 'syntax error in line 40' was the result of your one week wait. We had purchased a Timex Sinclair but it was never set up as a workstation in the classroom as was the TRS-80. The TRS-80 became our first 'in-class' computer. The local Radio Shack outlet (in the Brantford Mall at the time) had very generously provided a unit for us to borrow and use for a full semester and we made application for funding to purchase a single unit for the school for the following school year. I expected that the unit would be purchased from the store that had provided us with the loaner. Aware of the boards tendering policy I asked if I could identify a vendor if all tenders were the same and I was assured that all Radio Shack outlets would tender the same purchase price. I was assured that this would not be a problem and naturally indicated my preference that the local Radio Shack store would receive the order. I remember checking with the local store several times over the summer but each time the local store owner had received no word from the board. Going into the school in August as the new school year approached I was surprised by finding a TRS-80 sitting on one of the desks in one of the classrooms. Apparently all tenders were not the same and the Radio Shack outlet in Cambridge had undercut the Brantford outlet by $50 and thus received the order. Back then long distance charges were considerably more expensive than today and we had many questions about the use of our new TRS-80. I'm sure the $50 saving through the tendering process was used up many times over in long distance charges to our supplier in Cambridge. My best memory has to be the use of the audio cassette tapes that came with the unit to instruct the user. The same tape recorder that played the instructional tapes also saved the computer data. What year was that? Am I that old?
Phil Clayton on Sunday, May 10, 2009
This was my first computer ever. I purchased it in 1976, and had to finance the computer and monitor that cost me $599.00 This was a screaming fast CPU at 1.78Mhz, and 4KB RAM , Yes thats right 4,000 bytes memory. Enough to write about 20 lines of BASIC code before it ran out of memory. Heck my digital watch has more memory then it had. But I must say it was an amazing computer for its day, and I learned to write code, and changed careers as a Night Club Musician to owning my own computer business. That computer Changed my life..
Kay Gee on Friday, March 13, 2009
My God, my school got these when I was in the ninth grade; we were the only school in the state that had REAL COMPUTERS. I actually wish I had one of those reprehensible pieces of crap now.
Brian Boyes on Friday, December 22, 2006
My dad had friends at Radio Shack and we got one of the first model I's they had. We later upgraded it to 64Kb and an expansion station. We also bought a voice synthesizer and an adapter that allowed us to connect an Atari joystick. The thing I remember the most when programmers discovered they could make "sound" by clicking the tape contol port on and off at different frequencies. If you put an AM radio near the case it would pick up the interference generated by this and could make sounds, music and even voice. Probably one of the first PCs to have sound written into the games.
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