I recently had a Magnum Tecnologies Phoenix GS CNC Router donated to my high school shop program. With the exception of a few broken switches it was in quite good condition. Any way I replaced the switches and fired it up. Using the manual controls I moved all the axis', turned the router on and off etc. Everything moved as expected. The next time I turned it on the x axis failed to move. In the process of trouble shooting I discovered the board driving the x-axis blew its fuse. Switching the remaining 2 boards about (3 identical Centroid1 controller boards) restored motion to the x axis indicating a problem with the board and not the stepper motor. An examination of the faulty controller board shows no visibly damaged components, but a check with a volt meter shows a direct short across the positive and negative power input terminals. I have no documentaion on this machine. Has anyone experienced a similiar problem or does anyone have an idea where I could find a schematic. There are eight SCR's on the board which look like they are in the power input circuit. Would these be a logical point of failure? Any help would be appreciated.