GCA5200T and GCA1943T Transistors

The PBM8 500 MKII has six power transistors per channel. The photograph shows one side of the channel with the transistors removed. When removing the solder, application of minimal heat is required, otherwise the copper pads may detach. I also created a sketch showing the order in which the transistors were installed so that the new ones could be replaced in the correct order.

Shorted Transistors

The factory fitted transistors were GCA1943T and GCA5200T. I tested these with a continuity check and found them to be short between their junctions. When these transistors failed they shorted between all three terminals, and the short was easy to detect.

Transistor Order

Here is a quick sketch to show how the transistors line up. The other side mirrors of course.

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