Reference sheet in PDF form, 151 KB, covering the 2SD1830. The catalogue lists it as a schematic, but the name is a JIS transistor number, so it is probably a datasheet. 2SD denotes an NPN low-frequency bipolar device. Before replacing a failed part, read the collector-emitter voltage, collector current, dissipation and hFE ranks here. Also compare the package outline and lead order with the board footprint, because similar numbers can use different cases.
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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