请DX们鉴定一下该变压器

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输出为+12V +5V -12V -5V
用万用表量得    1     2      3      4-5      6       7
           1          0    0.049     0       0      0.049    
           2               0.049     0       0      0.049
           3                       0.049   0.049     0
           4                                 0      0.049
           5                                
           6                                        0.049
           7