请各位帮帮忙(已解决)

现在一款电源,空载输出电压是正常的,但它的空载开关管D极波形不正常,我调了两天反馈回路都没有改善,我现将变压器图纸,电路图和现在的空载波形传上来,请大家帮忙看看到底是什么问题.
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