TRS-80 Repairs – Model III / 4

How to Test the RS-232C Port on a Model III and 4 (c) Ian Mavric

Model III and 4 Checks Before Powering Up (c) Ian Mavric

How to Upgrade the CRT in a Model III and 4 (c) Ian Mavric

What to look For When Buying a Model III or 4 (c) Ian Mavric

Fixing Stuck Brightness/Contrast on a Model III or 4 (c) Ian Mavric

Repairing a Model 4 Serial Port (c) Ian Mavric

Upgrading RAM Badge on a Model III/4 (c) Ian Mavric

How to Fit a Model III Hi-Res Board in a Model 4 (c) Ian Mavric