Question about NEC AccuSync 90 19 in.CRT Conventional Monitor

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Accusync90 continues to burn out q505 (SCR), and Q504 (Horiz output). All this happened after the curcuit was shorted to ground by the support bracket that is under the center of the chassie. The short also burned that a hole through the board, I replaced six other componets by copying from another accusync 90 and had to straight wire the burned traces. This seems to be a design problem as the other was had shorted in the same place. I was able to repair that one. NO schematic available.

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