This won’t be a full on review and more of a briefer overview as I actually never did manage to restore my model II to working order before letting it go to someone that hopefully can but it is an interesting machine.
As you can tell by the above advertisement the Radio Shack TRS-80 Model II is a pure business machine, even more so then the earlier Model I. The Model II was released in 1979 and was squarely focused on the business world. The model II had either 32 or 64kb of RAM, a Z-80A CPU at 4mhz and used a different OS then the Model I (TRSDOS II) as well as CP/M, not that the original Model I was a hardcore gaming machine but the model II although more advanced was even less game friendly. I’m not going to go much farther into specifications since that can all be easily Googled so lets just go over the machine.
The computer itself is pretty heavy. This can mostly be attributed to the built in black and white CRT screen. The case itself is made of grey plastic. Its a fairly durable case overall but it does kind of feel cheap and you can cause cracks in it if your not careful. The power and reset switches are to the right of the monitor. The switches on my machines kind of felt a little loose and flimsy but I’m not sure if that’s a model II thing or was just my machine. They way the keyboard attaches is also rather odd-ball. instead of the cable coming off the keyboard its actually attached to the computer so its sort of backwards.
The other immediately noticed feature of the model II is the massive 8 inch floppy drive mounted next to the built in monitor. I’m sure there were other computers that used 8 inch drives but the model II is the only machine I’ve ever come across that uses one and may be the most common one to of used one. The floppies themselves held about 500kb of data which isn’t bad at all for 1979.
Here’s the monster of a drive.
And here is a floppy disk size comparison.
My machine gave a “boot error DC” that I never solved. I think it had to do with the floppy drive just not being set up or connected correctly but to be honest I never put to much effort into trying to solve this. apperently there are ways to add a 5 1/4 or even 3 1/2 drive but that begs the question of where/how would you mount them?
On the back of the machine we have ports to connect the optional disk expansion box which would give you the ability to add more Floppy drives or hard drive options. There’s a printer port and two serial ports as well as the AC power connector and a fuse.
speaking of the expansion box.
This is the very heavy expansion box. This one came with a second 8 inch floppy drive. This expansion box would be used to add more drives or hard drives. It has its own power supply built in and its own power switch.
Now will take a quick look inside the machine.
Most of the internal space is eaten up by the CRT tube as well as the 8 inch drive. The center board with what look like ISA slots (they are not) is how the various components interface with the TRS-80. The connected boards are separate floppy controllers and the CPU board which makes this machine interesting since its not made up of one integrated motherboard. I would of liked to pull each board and photograph it but I was a little pressed for time and the bar that hold these boards was pretty firmly screwed in and I just didn’t feel like dealing with it and possibly messing something up.
I did though take a short video of this machine powering up which sounds like a 747 powering up for lift off.
So that’s about all for the model II. Its a very interesting machine but squarely focused at the 1979 business market if you want to get into the TRS-80’s I’d suggest a model I or perhaps a model III/IV if you can find one.
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