Archive named only m526, a 2.59 MB ZIP whose name reveals no brand, board number or document type. The token may be a model code, yet that is not certain, so the contents must be checked after extraction. If the package holds schematics, a boardview or a service manual, compare the model and board revision printed on the device with those documents first. Mismatched hardware revisions are a common cause of misleading measurements and wrong part orders during repair.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @uzb4422. Enginerys does not host this file.
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