Here is the 2SD1825 in PDF format, 150 KB, listed under schematics though the name suggests a transistor datasheet rather than a circuit diagram. The 2SD prefix in JIS numbering stands for an NPN low-frequency bipolar transistor. Rating tables, characteristic curves and the outline drawing help with in-circuit testing and choosing a substitute of equal or higher voltage and current. Verify lead order against the board footprint first.
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 @cyberlanelectonik. Enginerys does not host this file.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.
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