You who follow my correspondence here will know all about my TRS-80 Model 100, which sees use mostly as a timelapse camera controller. I also have a pair of Tandy Model 200’s, which are the rarer version and are basically the same machine with a few improvements like a much larger screen that folds clamshell-style and 3 banks of 24k RAM rather than 1 bank of 32k RAM.
One of these T200’s I picked up a few years ago in trade, and it would turn on, but nothing would come up on the screen. At the time, I took it apart in the same way you’d take a Model 100 apart: by removing the 4 screws at the bottom, which are the only screws accessible from the outside. This is what I found.
The video ribbon cable was separated from it’s plug, and there’s no way you can plug it back in (it’s way too short). Well, after several attempts, I put it back together with the cable still disconnected and tossed it into the “future projects” pile.
Fast forward to today, when I was suddenly struck with the idea to RTFM. The Service Manual has to be somewhere on the web, right? Ayup, it was. Club100 to the rescue!
Turns out the obvious way is the wrong way. You have to take the screen off first, as illustrated below. With the screen off, the ribbon cable has a straight path to the motherboard socket and can easily be re-attached. The illustration is slightly misleading – it shows an arrow implying you pull the front plastic bit off, but you actually press the center with your thumb and it easily unsnaps and comes loose.
And there we go. I had to reverse the cable to get it to plug in right. This put the aging folds of the cable in different places, so to distribute future wear on parts not already stressed by 30 years of opening and closing. Should last another 30 (or it better, it’s not like I can order a replacement from the Rat Shack anymore.)
So there you are. I imagine this video cable issue plagues anyone who has taken apart a T200 without reading the Service Manual first, so hopefully this post will save someone a great deal of frustration. (: