I was given an old Tandy 3 microcomputer. The button on the right side of the keyboard says "48K." Was this computer a newer version of the TRS-80 Model III? I am going to try and restore this computer. Right now it has a video problem. The screen lights up and has zig-zags on the screen. Also the contrast and brightness knobs are frozen and move just a little bit left or right. --Alan